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Hospital Corpsman 3 &
2: June 1989
Chapter 7: Pharmacology and Toxicology
Naval Education and Training Command
Introduction
As you advance in rate, you will become more and more
involved with the intricacies of administering medicines. Although
the drugs and their dosages are prescribed by the medical officer
and other authorized prescribers, you, as the hospital corpsman,
are involved in their administration. It is necessary for you to
learn their sources, composition, methods of preparation and
administration, and physiologic and toxicologic action. This
chapter is concerned primarily with the action, use, and dosage of
drugs.
The subject of pharmacology was known as Materia Medica
until 1890 when the current term began to come into use. The
subsciences of pharmacology and their specific fields of study are
as follows:
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Pharmacognoscy - The recognition, quality, purity,
and identification of drugs.
Pharmacy - The preparation, stability,
preservation, and storage of pharmaceutical preparations.
Dosology - Dosage or amount of drug to be
given.
Pharmacodynamics - The response of living
tissue to chemical stimulation in the absence of disease. This
almost exclusively deals with research and development.
Pharmacotherapeutics - The action of drugs on
living tissue in the presence of disease; treatment of the
sick.
Toxicology - The toxic or poisonous effects of
substances.
The art of treating disease by any method that will
relieve pain, cure disease, or prolong life is called
therapeutics. Although the average person thinks solely of giving
or taking medicine in this respect, it must be remembered that
therapy also includes other methods, such as radiological
treatment, diathermy, hydrotherapy, and many more.
Drug Standards
The texts dealing with pharmaceutical preparations
include the United States Pharmacopeia and National Formulary
(USP-NF) which provides standards for drugs of therapeutic
usefulness and pharmaceutical necessity. Inclusion of drugs into
this compendia is based on therapeutic effectiveness and
popularity. It provides tests for identity, quality, strength, and
purity.
The Physicians'Desk Reference is a multiple index of
commercially available drugs and is used as an advertising outlet
for various drug manufacturers. Pharmaceutical preparations are
described as to composition, action and use, administration and
dosage, precautions and side effects, dosage forms available, and
the common (generic) name of the drug.
Remington's Pharmaceutical Sciences is probably the most
widely used text/reference in American pharmacy. It contains all
areas relevant to the art/science of pharmacy. The Pharmaceutical
Basis of Therapeutics (Goodman and Gilman) is a textbook of
pharmacology, toxicology, and therapeutics known as the "blue
bible" of pharmacology.
Medication Administration
The quantity of a drug to be administered at one time or
the total quantity administered and the method of administration
of drugs is dependant upon several factors. This section will
cover some of the methods of administration and some of the
factors affecting dosage calculations.
Dosage
The amount of medication to be administered is
referred to as the dose. The study of dosage and the criteria
which influence it is called posology. The doses given in the
United States Pharmacopeia and National Formulary (USP-NF) are
average therapeutic doses and are known as "usual adult doses."
The following terms are used in connection with doses:
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Therapeutic dose - Also referred to as the normal adult
dose, the usual dose or average dose, it is the amount
needed to produce the desired therapeutic effect. This is
calculated on an average adult about 24 years old, weighing
approximately 150 pounds.
Dosage range - A term that applies to the range
between the MINIMUM amount of drug and the MAXIMUM amount of
drug required to produce the desired effect. Many drugs,
such as antibiotics, require large initial doses that are
later tapered to smaller amounts. Closely associated with
this term are MINIMUM dose, the least amount of drug
required to produce a therapeutic effect; MAXIMUM dose, the
largest amount of drug that can be given without reaching
the toxic effect; and the TOXIC dose, the least amount of
drug that will produce symptoms of poisoning.
Minimum lethal dose - The least amount of drug
than can produce death.
Factors Affecting Dosage
In the administration of medicines there are many
factors that affect the dose, method of administration, and
frequency of the dose. Although a physician prescribes the
amount to be given, you need to know how and why these
quantities are determined. The two primary factors that
determine or influence the dose are age and weight.
Age
Age is the most common factor that influences the
amount of drug to be given. An infant would require much
less than an adult. Elderly patients may require more or
less than the average dose, depending upon the action of the
drug and the condition of the patient.
The rule governing calculation of pediatric doses
is Young's Rule as shown below:
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Age in
years
Age in years + 12
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x
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Adult dose = child's dose
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The age in years of the child is the numerator and
the age plus 12 is the denominator. This fraction is
multiplied by the normal adult dose.
Example: The adult dose of aspirin is 650 mg. What
is the dose for a 3-year-old child?
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3
3 + 12
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x
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650 mg
15
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= 130 mg
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Weight
In the calculation of dosages, weight has a more
direct bearing on the dose than any other factor, especially
in the calculation of pediatric doses. The rule governing
calculation of pediatric doses based on weight is Clark's
Rule shown below:
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Weight of child
(pounds)
150 pounds
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x Adult's dose = Child's dose
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The weight in pounds is the numerator and the
average adult weight, 150 pounds, is the denominator. This
fraction is multiplied by the adult dose.
Example: The adult dose of aspirin is 650 mg. What
is the dose for a child weighing 60 pounds?
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60 pounds
150 pounds
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x 650 mg = 260 mg
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Other factors that influence dosage are:
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Sex. Females usually require smaller doses than
males.
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Race. Blacks usually require larger doses and Asians
smaller doses than Caucasians.
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Genetic make-up. The genetic structure of the
individual may cause peculiar reactions to medications in
some patients.
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Occupation. Persons working in strenuous jobs may
require larger doses than those who sit at a desk all
day.
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Habitual use. Some patients must take medications
chronically, causing their bodies to build up tolerance
to the drug. This tolerance may require larger doses than
their initial doses to obtain the same therapeutic
effect.
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Time of administration. Therapeutic effect may be
altered depending upon time of administration. Example:
Before or after meals.
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Frequency of administration. A drug given frequently
may need a smaller dose than if administered at longer
intervals.
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Mode of administration. This has a definite impact on
the dose. Example: Injections
Methods of Administering Drugs
Drugs are introduced into the body by different
routes, each serving a specific purpose.
Oral
Oral administration of medications is the most
common method. Advantages are (1) convenience, (2) economy,
(3) the drug need not be absolutely pure or sterile, and (4)
a wide variety of dosage forms are available. Oral
medications include tablets, capsules, liquids, and
suspensions. Disadvantages include (1) inability of some
patients to swallow, (2) slow absorption, and (3) partial or
complete destruction by the digestive system. Other routes
associated closely with oral administration are SUBLINGUAL
and BUCCAL.
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Sublingual-The drug is placed under the tongue and
rapidly absorbed directly into the blood stream. Example:
Nitroglycerin sublingual tablets
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Buccal-The drug is placed between the cheek and gum
and is quickly absorbed directly into the blood
stream.
Parenteral
Parenteral medications are those introduced by
injection. All drugs used by this route must be pure,
sterile, pyrogen-free (pyrogens are products of the growth
of microorganisms), and in a liquid state. There are several
types of parenteral administration.
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Subcutaneous-The agent is injected just below the
skin's cutaneous layers. Example: Insulin
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Intradermal-The drug is injected within the dermis.
Example: Purified protein derivative (PPD)
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Intramuscular-The drug is injected into the muscle.
Example: Procaine penicillin G
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Intravenous-The drug is introduced directly into the
vein. Example: Intravenous fluids
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Intrathecal/intraspinal-The drug is introduced into
the subarachnoid space of the spinal column.
Inhalation
Inhalation is the introduction of medications
through the respiratory system in the form of a gas, vapor,
or powder. Inhalation is divided into three major types:
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Vaporization-This is where the drug is changed from a
liquid or solid to a gas or vapor by the use of heat,
such as steam inhalation.
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Gas inhalation-It is almost entirely restricted to
anesthesia.
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Nebulization-The drug is nebulized into minute
droplets by the use of compressed gas.
Topical
Ointments, creams, lotions, and shampoos are
examples of topical preparations. Topical application serves
two purposes: (1) local effect-the drug is intended to
relieve itching, burning, or other skin conditions without
being absorbed into the bloodstream and (2) systemic
effect-the drug is absorbed through the skin into the
bloodstream. Example: Nitroglycerin paste
Rectal
The rectal method is preferred to the oral route
when there is danger of vomiting or when the patient is
unconscious, uncooperative, or mentally incapable.
Vaginal
Suppositories, creams, or tablets are examples of
vaginal preparations which are inserted into the vagina to
produce a local effect.
Drug Classifications
The definition of a drug is any chemical substance that
has an effect on living tissue but is not used as a food. Drugs
are used on or administered to humans or animals as an aid in the
diagnosis, treatment, or prevention of disease or other abnormal
condition, for the relief of pain or suffering, or to control or
improve any physiologic or pathologic condition. A drug may be
classified in various categories, depending upon different
criteria. Examples are general, chemical, and therapeutic.
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General-Drugs are grouped according to their source,
whether animal, vegetable, or mineral in origin.
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Chemical-Medications are grouped by their chemical
characteristics. Examples are acids, bases, or salts.
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Therapeutic (Pharmacological)-Drugs are classified
according to their action on the body. A drug may have more
than one action.
Nomenclature
Drugs normally have three different names: chemical,
generic, and trade (brand).
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Chemical name-Tells the chemical and molecular structure.
An example is 2, 4, 7-triamino-6-phenylpteridine.
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Generic name-Often derived from the chemical name, it is
the common name of the drug. An example is Triamterene. Note
the underlining of the chemical name above.
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Trade name-This is the name given by the manufacturer and
is a proprietary name, it is also called the brand name. An
example is Dyrenium, a brand of triamterene made by Smith,
Kline, and French.
Drug Groups
The drugs discussed in this chapter are those in common
use, or are in the Medical Stock List, and are grouped according
to pharmacological classes. Only a brief summary is possible here
and the corpsman who desires a more complete study of each drug
should refer to the USP-NF or other reference books indicated at
the end of this chapter.
Antacids
Antacids are drugs used to counteract hyperacidity in
the stomach. Normally, there is a certain degree of acidity in
the stomach. An excess of acid can irritate the mucous
membranes and is commonly known as indigestion, heartburn, or
dyspepsia. In some disease states, the gastrointestinal tract
may become excessively acidic (very low pH), causing diarrhea
or leading to peptic ulcer formation. Antacids may interfere
with the body's ability to utilize many drugs. For this reason,
most oral drugs should not be taken within 2 hours of taking an
antacid. NOTE: As a hospital corpsman, it is important to be
aware of the significance of the sodium content of most
antacids, particularly in the cardiac patient or patients on a
low sodium diet.
Action and Use - Milk of magnesia reacts
with gastric acid to form magnesium chloride and has a
prolonged duration of action. It is preferably taken on an
empty stomach with lots of fluid. Do not use when abdominal
pain, nausea, or vomiting is present. Shake well. Prolonged
use may result in kidney stones. It also has a laxative
effect.
Usual Dose - 5 to 10 ml four to six times a
day, up to a maximum of 60 ml. Laxative dose is 15 to 30
ml.
Action and Use - This drug is used in the
management of peptic ulcer, gastritis, and gastric
hyperacidity. The major advantage of this drug is that no
systemic alkalosis is produced. It may cause
constipation.
Usual Dose - 15 ml four to six times daily
between meals and at bedtime.
Action and Use - Alumina and magnesia oral
suspension coats the stomach lining and neutralizes gastric
acid. It is less constipating than aluminum hydroxide
alone.
Usual Dose - 5 to 20 ml 1 hour after each
meal and at bedtime.
Action and Use - This drug coats the
stomach lining, neutralizes gastric acid, and reduces
flatulence.
Usual Dose - 5 to 10 ml 1 hour after meals
and at bedtime.
Action and Use - Magaldrate is the same as
alumina and magnesia oral suspension, but is has a lower
sodium content.
Usual Dose - 5 to 10 ml between meals and
at bedtime.
Astringents
Astringents are drugs that cause shrinkage of the
skin and mucous membranes. They act by precipitating the
proteins on the surface layer of the skin and mucus membranes.
Their main use is to stop seepage, weeping, or discharge from
mucous membranes.
Action and Use - This drug is an astringent
wet dressing for the relief of inflammatory conditions of
the skin, such as poison ivy, swellings and bruises, insect
bites, athlete's foot, or other environmental skin
conditions and for superficial external otitis.
Usual Dose - Topical, in a 1:10 to 1:40
solution.
Action and Use - Calamine lotion is used in
the treatment of various skin afflictions in the same way as
aluminum acetate. It is an astringent and protective, which
is used externally. It should not be applied to blistered,
raw, or oozing areas of the skin.
Usual Dose - Apply to the affected area two
to four times daily and at bedtime.
Adsorbents
An adsorbent is a drug that attaches another
substance to its surface. These drugs are used to adsorb
undesirable substances.
Action and Use - This drug forms an
effective barrier between any remaining particulate material
and the gastrointestinal mucosa, thus inhibiting
gastrointestinal absorption. It is used as an emergency
treatment in poisoning by most drugs and chemicals.
Usual Dose - 30 to 100 g within 30 minutes
after ingestion of toxic substances. It is administered as a
slurry and ingested by the patient or administered through a
nasogastric or lavage tube.
Emollients
Emollients are bland or fatty substances that may be
applied to the skin to make it more pliable and soft, and may
also serve as vehicles for application of other medicinal
substances. They are available as ointments, creams, or
lotions. Examples not discussed include Keri-Lotion,
Eucerin-Lotion, and Lubriderm.
Action and Use - Cocoa butter is an
excellent emollient with a pleasant odor. It is ideal for
the treatment of chapped skin and lips, cracked nipples, or
minor irritated or abraded skin areas.
Action and Use - This is a smooth creamy
ointment of wool fat. It is an ideal emollient for dry,
scaly skin conditions.
Action and Use - Petrolatum is a highly
occlusive and good emollient. It may not release some drugs
when used as an ointment base.
Action and Use - This is a white petrolatum
containing approximately 20 percent zinc oxide powder. It is
used as an emollient with slightly astringent properties,
and because of its opaqueness it is ideal for protecting
sensitive skin from the sun.
Expectorants and Antitussives
Expectorants, more accurately known as bron
chomucotropic agents, are drugs used to assist in the removal
of secretions or exudate from the trachea, bronchi, or lungs.
They act by liquifying viscid mucus or mucopurulent exudates,
i.e., they are decongestants. Therefore, they are used in the
treatment of coughs to help expel these exudates and
secretions. Antitussives are agents that specifically inhibit
or suppress the act of coughing. They should not be used to
suppress productive coughing. Expectorants and antitussives are
most commonly used in the symptomatic treatment of the common
cold or bronchitis. Other cold and allergy relief preparations
are discussed later in this chapter.
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Guaifenesin (Robitussin)
Action and Use - Guaifenesin is an expectorant.
It may be useful in the symptomatic relief of dry,
nonproductive coughs and in the presence of mucous in the
respiratory tract.
Usual Dose - 5 to 20 ml every 4 to 6
hours.
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Dextromethorphan (DM)
Action and Use - This is a synthetic
non-narcotic derivative of codeine that acts as an
antitussive. It is used to control nonproductive coughs by
soothing minor throat and bronchial irritations.
Usual Dose - 5 to 15 ml (10 to 30 mg) every
6 to 8 hours. It is frequently combined with Guaifenesin
(Robitussin).
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Benzonatate (Tessalon Perles)
Action and Use - Benzonatate is an
antitussive. It anesthetizes the stretch receptors located
in the respiratory passages and lungs, reducing the cough
reflex at its source. It is used for the symptomatic relief
of nonproductive coughs.
Usual Dose - One perle three times daily as
needed, up to 600 mg a day.
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Terpin Hydrate Elixir with Codeine (ETH with
Codeine)
Action and Use - Codeine is a narcotic
antitussive. The terpin hydrate is used primarily as a
vehicle for the codeine but has a mild expectorant effect.
This product contains 40 percent alcohol which serves as the
main bronchomucotropic agent.
Usual Dose - 5 ml every 3 to 4
hours.
Antiseptics, Disinfectants and
Germicides
These drugs are primarily intended for the prevention
of infections by destroying bacteria or preventing their
growth. The differences among them are based primarily on
degree of activity and how they are used; antiseptics suppress
the growth of microorganisms and are used topically; germicides
kill susceptible organisms; and disinfectants are agents used
on inanimate objects and are primarily germicidal in their
action. All of these agents are for external use only unless
otherwise indicated.
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Phenol (Carbolic Acid)
Historically one of the first antiseptic agents
used, phenol is the standard by which all other antiseptic,
disinfectant, and germicidal agents are measured in their
effectiveness. Because of its highly caustic nature, it must
be handled with care. The effect of phenol is coincident
with the concentration; high concentrations are germicidal
and can cause tissue destruction; lower concentration are
antiseptic. Phenol is inactivated by alcohol. Because more
effective and less damaging agents have been developed,
phenol is no longer used extensively. Never use phenol to
disinfect rubber, cloth, or plastic.
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Povidone-Iodine
(Betadine)
Action and Use - Numerous iodine and iodine
complex agents are available for use in disinfection. The
most common of these is povidone-iodine (Betadine). It is
used externally to destroy bacteria, fungi, viruses,
protozoa, and yeasts. It is relatively nontoxic,
nonirritating, and nonsensitizing to the skin. When used as
an antiseptic, the complex breaks down on contact with skin
or mucous membranes to release free iodine which is slowly
absorbed. It is most commonly used as a preoperative skin
antiseptic.
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Isopropyl Alcohol
(Isopropanol)
Action and Use - This is used in a 70
percent solution as a skin antiseptic; it is volatile and
also has a desiccating (drying) effect on the skin.
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Hexachlorophene
(pHisoHex)
Action and Use - A synthetic preparation,
hexachlorophene is a bacteriostatic cleansing agent most
effective against gram positive organisms. Pus or serum
decrease the efficacy. Hexachlorophene is a neurotoxic agent
and must not be used on premature infants, denuded skin,
burns, or mucous membranes. It is used as an antiseptic
scrub by physicians, dentists, food handlers, and others.
Residual amounts can be removed by alcohol.
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Silver Nitrate
Action and Use - The soluble salts of
silver ionize in water to produce solutions that are
astringent and antiseptic in high concentration. In solid
form, silver nitrate is most commonly used to cauterize
mucous membranes or treat aphthous ulcers. The most common
side effect is the skin turns black where the silver nitrate
has come into contact with it. This black area is slow to
absorb but is not harmful. In liquid form, it is used to
prevent gonorrheal ophthalmia in the newborn (eye drops) or
as a wet dressing on burns. Caution must be taken to keep
the dressing wet; silver will precipitate from a drying
dressing and can be absorbed through the skin. The effect is
a condition known as agyria, where the skin turns a slate
gray. There is no known reversal for this condition.
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Benzalkonium Chloride (Zephiran Chloride)
Action and Use - A somewhat effective,
non-injurious surface disinfectant, benzalkonium chloride is
germicidal for a number of gram-positive and gram-negative
organisms including some fungi. It is inactivated by soap or
alcohol, and is not effective against spores or viral
pathogens. It is most commonly used as a cleansing agent in
animal bites.
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Glutaraldehyde (Cidex)
Action and Use - Glutaraldehyde is
effective against vegetative gram-positive, gram-negative,
and acid-fast bacteria, bacterial spores, some fungi, and
viruses. It is used in an aqueous solution for sterilization
of fiber optics, plastics, rubber, and other materials that
are not resistant to heat.
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Thimersol (Merthiolate)
Action and Use - An organic mercury
compound, thimersol is non-irritating to the skin and mucus
membranes when applied topically. It has antiseptic,
germicidal, and fungicidal properties.
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Hydrogen Peroxide
Action and Use - Certain oxidizing agents
are destructive to pathogenic organisms but mild enough to
be used on living tissue. Hydrogen peroxide is a germicide
that is active by the release of oxygen. It deteriorates on
standing to oxygen and water. It is most commonly used to
clean suppurating wounds, and is also efficious in the
treatment of Vincent's angina (trench mouth). For external
use only, it is available as a 3 percent solution.
Anti-Infectives
Antibiotics are chemical compounds produced as the
result of metabolic activity of micro-organisms or produced
synthetically. They inhibit the growth of susceptible
microorganisms or kill them through the destruction of
necessary enzymes. Antibiotics that are sufficiently non-toxic
to the host are used as chemotherapeutic agents in the
treatment of infectious diseases of man, animals, and plants.
They can be administered orally, topically, or
parenterally.
Antibacterial Agents
The five basic mechanisms of action for the
antimicrobial agents are
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inhibition of the synthesis of the bacterial cell
wall,
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affecting the cell wall permeability,
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inhibition of protein synthesis by affecting
ribosomal activity,
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affecting nucleic acid metabolism, and
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the antimetabolites that compete with necessary
enzymes.
To be of practical value in the treatment of infection, an
antimicrobial agent must exert it effects upon the invading
microorganism without seriously damaging the cells of the
host. The following are groups of antimicrobial agents and
their general mechanisms of action.
Sulfonimides
The sulfonimides were the first effective
chemotherapeutic agents to be available in safe therapeutic
dosage ranges. They were the mainstay of therapy of bacterial
infections in humans before the introduction of the penicillins
in 1941. All the sulfonimides are synthetically produced and
contain the para-amino-benzene sulfanilamide group. The
spectrum of activity for all the sulfonimides is similar and
all are effective against both gram-positive and gram-negative
organisms. They are primarily bacteriostatic and act as an
antimetabolite (competitor) to para-aminobenzoic acid (PABA) in
susceptible organisms. PABA is required in the formation of
folic acid.
Excretion of the sulfonimides is chiefly through the
kidneys. Some of the sulfonimides are relatively insoluble in
acidic or neutral solutions so there is some danger that a
sulfonimide would precipitate out of solution leading to
crystal formation, hematuria, or possibly renal shutdown.
Forcing fluids to keep the urine dilute or administering
alkaline solutions can help to prevent precipitation of
sulfonimides. With the newer sulfonimides, this is not a major
concern since many of them are soluble in acidic solutions.
Although the sulfonimides have, for the most part,
been replaced with other agents, there is still a significant
demand in certain types of infection, most notable urinary
tract infections, such as acute cystitis or prostatitis, and in
cases of acute otitis media. The following lists some of the
more common sulfonimides.
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Sulfisoxazole
(Gantrisin)
Action and Use - This systemic sulfonimide
is bacteriostatic and is indicated in the treatment of
urinary tract infections and acute otitis media.
Usual Dose - 2 to 4 g initially, then 1 to
2 g four times daily for 10 days. The patient should be
advised to increase fluid intake.
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Trimethoprim and Sulfamethoxazole
(Bactrim, Septra)
Action and Use - This is an
antiinfective combination used in the treatment of urinary
tract infections and otitis media. Both drugs are effective
antimetabolites but compete at different steps in the
formation of PABA. In combination, they are more effective
than individually.
Usual Dose - Two tablets every 12 hours.
The patient should be advised to increase fluid intake.
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Sulfacetamide (Sulamyd)
Action and Use - Sulfacetamide is an
ophthalmic bacteriostatic for the treatment of
conjunctivitis, corneal ulcer, and other superficial ocular
infections. It is available in solutions of various
strengths and in an ointment form. Sulfacetamide is
inactivated by the para-aminobenzoic acid in purulent
exudates.
Usual Dose - Solutions of 1 to 2 drops
three or four times daily depending on the severity of the
infection. The ointment should be applied four times
daily.
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Silver Sulfadiazine
(Silvadene)
Action and Use - Silver sulfadiazine is a
topical antimicrobial agent used in the treatment of second-
and third-degree burns to prevent wound sepsis. It is water
soluble and easily washed off the skin.
Usual Dose - Silver sulfadiazine is
available in an emollient cream and should be initially
applied to a burn wound twice daily in a sterile manner. For
each dressing change, the burn wound should be debrided of
any dead or sloughing tissues and carefully cleaned to
remove any residual purulent exudate.
Penicillins
Penicillin is one of the most important of the
antibiotics. It is derived from a number of Penicillium molds
commonly found on breads and fruit. The mechanisms of action
for the penicillins is the inhibition of cell wall synthesis
during the reproductive phase of bacterial growth. It is one of
the most effective and least toxic of the antimicrobial
agents.
Benzylpenicillin (Penicillin G) is the prototype form
for all the penicillins. It is highly effective against many of
the gram-positive cocci, and, to a lesser extent, the
gram-negative cocci. Semisynthetic preparations have been
produced to attempt to overcome some of the problems of the
naturally occurring penicillins, i.e., instability in an acid
medium, rapid renal excretion, susceptibility to penicillinase,
and a high incidence of hypersensitivity. Significant
differences among the agents include resistance to gastric acid
inactivation, resistance to inactivation by penicillinase, and
the spectra of antimicrobial activity.
Although the penicillins are virtually nontoxic to
mammalian cells, there is a significant incidence of
anaphylaxis in varying degrees. Reactions include skin rash,
contact dermatitis, mild gastrointestinal upset, oral lesions,
and fever. Because of the basic structure, there is a high
degree of cross-sensitivity among the various forms.
Penicillin is effective in the treatment of:
-
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Bacterial endocarditis and pneumococcal
infections
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Hemolytic streptococcal infections
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Clostridial infections such as gas gangrene
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Anaerobic streptococcal infections
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Gonococcal infections
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Anthrax
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Vincent's angina
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Syphilis
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Rheumatic heart fever
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Penicillin G (Aqueous)
Action and Use - Penicillin G is indicated
for susceptible infections as listed under the discussion of
penicillins. It is available as a potassium or sodium salt
and is for parenteral use only.
Usual Dose - The dosage varies with the
infection. Doses of 10 million units or higher should be
given by intravenous infusion only.
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Penicillin G Procaine, Aqueous
(Wycillin)
Action and Use - Penicillin G procaine is
indicated for deep intramuscular usage only in susceptible
infections as listed under the discussion of penicillins.
The action is more prolonged than penicillin G.
Usual Dose - For uncomplicated gonorrhea,
4.8 million units intramuscularly at two sites with 1 g of
probenicid orally. Other dosages are as prescribed by the
physician.
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Penicillin G Benzathine
(Bicillin)
Action and Use - This drug is indicated for
deep intramuscular usage in susceptible infections. It has a
longer duration of action than most of the other
penicillins.
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Penicillin V Potassium
(Phenoxymethyl Penicillin) (Pen-Vee K, Betapen-VK, V-Cillin K)
Action and Use - Penicillin V is used in
the treatment of susceptible infection as listed under the
discussion of penicillins. It is available as oral tablets
or powder for reconstitution for oral suspension. It is more
stable in acid media than most of the other penicillins. It
has the same spectra of activity of penicillin G and is
usually the drug of choice for uncomplicated group A
beta-hemolytic streptococcal infections.
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Dicloxicillin
(Dynapen)
Action and Use - This drug is a
penicillinase-resistant penicillin effective in treating
penicillinase-producing staphylococci. It may be used to
initiate therapy in any patient in whom a staphylococcal
infection is suspected.
Usual Dose - 250 to 500 mg every 6 hours.
It is available in capsules or powder form for oral
suspension.
-
Ampicillin (Polycillin,
Omnipen, Totacillin)
Action and Use - Ampicillin is relatively
stable in an acid medium and is readily absorbed after oral
ingestion. It is effective against gram-negative and
gram-positive cocci and some gram- negative bacilli. It is
available in both oral and parenteral forms.
Usual Dose - The range is 250 to 500 mg
every 6 hours, depending upon the diagnosis. For the
parenteral dosage, normal saline is the recommended
diluent.
-
Methicillin Sodium (Staphcillin)
Action and Use - Methicillin is a
penicillinase-resistant drug reserved for treatment of
penicillinase-producing staphylococcal organisms. It is
administered parenterally only.
Usual Dose - 1 g every 6 hours as directed
by the physician, intramuscularly or intravenously.
-
Nafcillin (Nafcil, Unipen)
Action and Use - Nafcillin is stable in
acidic solution, soluble in water, and readily absorbed. Its
action and effect are similar to the other
penicillinase-resistant penicillins. Like methicillin,
nafcillin is reserved for penicillinase-producing
staphylococcal infections and should not be used for
organisms susceptible to penicillin G.
Usual Dose - 500 mg or 1 g every 4 to 6
hours as directed by the physician.
Cephalosporins
The cephalosporins are a group of semisynthetic
derivatives of cephalosporin C, an antimicrobial agent of
fungal origin. They are structurally and pharmacologically
related to the penicillins. Because the cephalosporins are
structurally similar to the penicillins, some patients allergic
to penicillin may be allergic to a cephalosporin drug. The
incidence of cross-sensitivity is estimated to be 5 to 16
percent. Their antibacterial activity is due to inhibition of
cell wall synthesis.
This family of antibiotics is generally divided into
generations: first generation, cephadrine and cefazolin; second
generation, cefoxitin, and third generation, cefotaxime. The
main differences between groups is the change in the
antibacterial spectrum. The third generation agents have a much
broader gram-negative spectrum than the earlier
generations.
-
Cefazolin (Ancef, Kefzol)
Action and Use - Cefazolin is indicated for
susceptible infections due to Streptococcus pneumoniae,
Klebsiella, Hemophilus influenzae, Staphylococcus aureus, E.
coli, and preoperative prophylaxis.
Usual Dose - It may be given
intramuscularly or intravenously from 250 to 500 mg every 8
hours; 1 to 1.5 g every 6 hours in life-threatening
infections.
-
Cephadrine (Anspor,
Velosef)
Action and Use - Cephadrine is indicated
for certain respiratory tract infection, otitis media,
certain urinary tract infections, infections of the skin and
skin structures, and other susceptible infections.
Usual Dose - It may be given parenterally
or orally. Orally, give 250 mg every 6 hours or 500 mg every
12 hours. Parenterally, give 2 to 4 g in equally divided
doses four times daily intramuscularly or intravenously.
-
Cefoxitin (Mefoxin)
Action and Use - Cefoxitin is used in the
treatment of susceptible gram-positive and gram-negative
bacteria.
Usual Dose - 1 or 2 g every 6 to 8
hours.
-
Cephalexin (Keflex)
Action and Use - Cephalexin is an oral
preparation indicated for the treatment of certain
respiratory tract infections including group A
beta-hemolytic streptococci, otitis media, certain urinary
tract infections, osteitis, infections of the skin and skin
structures, and other susceptible infections.
Usual Dose - 250 to 500 mg four times
daily.
-
Cephalothin (Keflin)
Action and Use - Cephalothin is a
broad-spectrum parenteral preparation indicated for serious
infections caused by susceptible microorganisms specifically
S. pneumoniae, P. mirabilus, Klebsiella, and E. coli. It is
also indicated as a prophylactic measure in certain surgical
procedures that are considered contaminated or potentially
contaminated.
Usual Dose - The usual dose is 500 mg to I
g every 4 to 6 hours; 500 mg every 6 hours is usually
adequate in uncomplicated infections.
Tetracyclines
The tetracyclines, introduced in 1948, were the first
truly broad-spectrum antibiotics. They include a large group of
drugs with a common basic structure and chemical activity. The
most important mechanism of action of the tetracyclines is
blocking the formation of polypeptides used in protein
synthesis. Because of their broad spectrum of activity,
tetracyclines are most valuable in the treatment of mixed
infection, such as chronic bronchitis and peritonitis; however,
they are drugs of choice for only a few bacterial infections.
Tetracycline is also used as a topical preparation in the
treatment of acne.
The tetracyclines are relatively non-toxic, the most
common side effects being mild gastrointestinal disturbances;
allergic reactions and anaphylaxis are rare. Administration to
children and pregnant women is not indicated because it may
produce discoloration of the teeth and depress bone marrow
growth. The major hazard of tetracycline therapy is the
overgrowth of resistant organisms, especially Monilia and
staphylococci.
Tetracyclines should not be administered with milk,
milk products, antacids or iron preparations; they combine with
metal ions to form nonabsorbable compounds.
-
Tetracycline Hydrochloride
(Achromycin)
Action and Use - Tetracycline hydrochloride
(TCN) is used in the treatment of infections caused by
Rickettsiae (Rocky Mountain spotted fever, typhus fever),
agent of lymphogranulomas venereum and granuloma inguinale,
and the spirochetal agent of relapsing fever. It is also
indicated for certain gram-negative microorganisms.
Tetracycline hydrochloride is indicated for severe acne as
an adjunctive therapy. Food and some dairy products may
interfere with absorption; antacids containing aluminum,
calcium, or magnesium impair absorption of the antibiotic as
well. Give the drug 1 hour before or 2 hours after
meals.
Usual Dose - 1 or 2 grams per day in two or
four equal doses, depending on the severity of the
infection.
-
Doxycycline Hyclate
(Vibramycin)
Action and Use - Doxycycline is active
against a wide range of gram-positive and gram-negative
microorganisms and has a low affinity for binding with
calcium. In addition to the conditions listed under
tetracycline, doxycycline is also indicated for the
treatment of uncomplicated chlamydial infections and
uncomplicated gonococcal infections.
Usual Dose - For most uncomplicated
infections, 200 mg the first day followed by a maintenance
dose of 100 mg per day for 7 to 10 days. For venereal
diseases, 200 mg per day for 7 days in equally divided
doses; for syphilis, 300 mg per day in equally divided doses
for 10 days. Intravenous infusion is indicated only when the
oral route is not indicated.
-
Minocycline Hydrochloride (Minocin)
Action and Use - Minocycline hydrochloride
is indicated for the same conditions as tetracycline
hydrochloride and doxycycline hyclate.
Usual Dose - The dosage ranges are the same
as for doxycycline hyclate.
Aminoglycosides
The aminoglycosides are a group of drugs sharing
chemical, antimicrobial, pharmacologic, and toxic
characteristics. They are effective against most gram-positive
and gram-negative organisms; the method of action is by
inhibiting protein synthesis. Aminoglycosides can cause varying
degrees of ototoxicity and nephrotoxicity, depending on the
particular agent and the dose. Toxicity is more prevalent in
the presence of renal impairment, in the very young or old,
dehydration, or with the use of diuretics. Because of their
high toxicity, they are not recommended when the infective
organism is susceptible to less toxic preparations.
-
Streptomycin Sulfate
Action and Use - Streptomycin sulfate is
indicated for all forms of mycobacterium tuberculosis; it
should be used only in conjunction with other
antituberculosis drugs, i.e., rifampin or isoniazid. It is
also indicated in the treatment of plague, tularemia,
chancroid, granuloma inguinale and some urinary tract
infections where the infectious agent has shown to be
susceptible to streptomycin and not susceptible to less
toxic preparations.
Usual Dose - The dosage ranges from 1 to 4
g daily depending on the disease condition and the condition
and age of the patient. Streptomycin is for intramuscular
use only.
-
Neomycin Sulfate
Action and Use - Neomycin sulfate is
effective against certain gram-negative and gram- positive
bacteria. Normally used as a topical preparation for the
treatment of skin infections, burn wounds, ulcers, and
dermatoses, it may be used orally for reduction of
intestinal flora prior to surgery involving the bowel or
anus.
Usual Dose - 700 mg every 4 hours as
prescribed by a physician.
-
Gentamycin Sulfate
(Garamycin)
Action and Use - Gentamycin sulfate is
indicated in the treatment of serious systemic infections of
susceptible gram-negative organisms. While the patient is on
gentamycin, it is necessary to monitor renal and hepatic
function to determine if toxic levels are reached.
Gentamycin is also available as a topical preparation for
the treatment of burns and infected wounds, and as an
ophthalmic preparation for eye infections.
Usual Dose - The recommended dose for
patients with serious infections and normal renal function
is 3 mg/kg/day in equally divided doses. Gentamycin is
normally administered intramuscularly but can be
administered intravenously.
Macrolides
The macrolide antibiotics constitute a large group of
bacteriostatic agents that inhibit protein synthesis. They are
effective against gram-positive cocci, Neisseria, Hemophilus,
and mycobacteria. All are similar to penicillin in their
antibacterial spectra and are often used in patients who are
sensitive to penicillin.
-
Erythromycin
(Ilotycin, Erythrocin, E-Mycin)
Action and Use - Because it has a bitter
taste and is destroyed by gastric acids, erythromycin is
usually administered as an enteric coated tablet.
Erythromycin is one of the drugs of choice when penicillin
is contraindicated. It is also available as an ophthalmic
ointment and as a topical preparation for the adjunctive
treatment of acne.
Usual Dose - 250 mg four times daily or 500
mg twice daily for oral preparations, and 1 g daily by slow
intravenous infusion or in four equally divided doses.
-
Clindamycin Hydrochloride
(Cleocin)
Action and Use - The use of clindamycin
hydrochloride has often been associated with severe colitis
and profuse diarrhea; if this condition occurs, the drug
should be discontinued. Clindamycin hydrochloride is
indicated in the treatment of susceptible anaerobic
organisms. A topical preparation is also available for the
treatment of acne.
Usual Dose - 150 to 300 mg every 6 hours
for the oral form and 600 to 1200 mg per daily in 2, 3, or 4
equally divided doses for the intravenous form.
-
Vancomycin Hydrochloride
(Vanocin)
Action and Use - Vancomycin hydrochloride
is bactericidal against many gram-positive bacteria. It is
indicated in potentially life-threatening conditions that
cannot be treated with less toxic preparations.
Usual Dose - 500 mg every 6 hours or 1 g
every 12 hours intravenously only; vancomycin hydrochloride
can be very irritating and painful when administered
intramuscularly.
Miscellaneous Antibiotics
In addition to the previously mentioned
antiinfectives, there are several other agents that are
effective in the treatment of different organisms.
-
Rifampin (Rifadin)
Action and Use - Rifampin is indicated in
the treatment of pulmonary tuberculosis; it must be used in
conjunction with at least one other antituberculosis agent,
usually ethambutol or
isoniazid.
Usual Dose - 600 mg in a single daily
administration throughout the course of the disease.
-
Isoniazid (INH)
Action and Use - Isoniazid is indicated in
the treatment of tuberculosis and as a preventive therapy
for high risk persons, i.e., positive tuberculin skin test,
family members of a person with tuberculosis, and newly
infected persons.
Usual Dose - 300 mg daily in a single dose.
Because the relapse rate is high, it is essential that the
treatment regimen be continued for a sufficient period of
time; routinely, this is considered to be 1 year. for
preventive therapy.
-
Chloramphenicol Sodium Succinate
(Chloromycetin)
Action and Use - Chloramphenicol was used
extensively when first developed because it had no apparent
side effects. It inhibits protein synthesis, is easily
absorbed from the gastrointestinal tract, and is effective
against most gram- positive and gram-negative organisms, and
against rickettsiae. Chloramphenicol has been recognized as
highly toxic with significant hematologic side effects;
i.e., bone marrow depression, anemia, and leukopenia.
Currently, it is normally used only for treatment of typhoid
and other salmonella, rickettsial diseases, and
gram-negative bacteremia resistent to other antibiotics.
Because of its serious toxic effects, it is reserved for
serious infections that are not amenable to treatment with
less toxic preparations.
Usual Dose - 50 mg/kg/day in divided doses
at 6 hour intervals. The oral method is the preferred method
of administration although intravenous infusion is
acceptable; intramuscular injection is ineffective.
-
Polymixin B Sulfate
(Aerosporin) and Polymixin E
Sulfate (Coly-Mycin S)
Action and Use - These are the only
polymixin complexes still in use. Because of their excessive
nephrotoxic nature, the other polymixin complexes have been
discarded. Polymixins act by disrupting the cytoplasmic
membrane of the cell causing immediate cell death. The
polymixins are bactericidal against almost all the
gram-negative bacilli; they are not effective against
gram-positive bacteria or fungi.
Usual Dose - Polymixin B sulfate is
available as a parenteral preparation for intravenous or
intrathecal administration; it should not be used
intramuscularly. The dosage is 15,000 to 25,000 units/kg/day
intravenously; 1 to 3 drops of a 0.1 to 0.25 percent
solution hourly for the treatment of conjunctivitis. The
preparation can also be used as an ophthalmic solution.
Polymixin E sulfate (colistin) is available as an oral
suspension for the treatment of diarrhea in children given
at 5 to 15 mg/kg/day. It is also available as an otic
suspension with neomycin and hydrocortisone for the
treatment of superficial bacterial infections of the
external auditory canal. The dose is 4 drops 3 or 4 times
daily.
-
Spectinomycin Hydrochloride
(Trobicin)
Action and Use - Spectinomycin was
developed with the sole therapeutic indication being the
treatment of gonorrhea. It is largely bacteriostatic and
quite effective in the treatment of uncomplicated gonorrhea.
Its advantage lies primarily in being a single dose therapy
and in patients who are allergic to penicillin or have
penicillin resistant strains of the causative organism. It
is NOT effective in the treatment of syphilis.
Usual Dose -A n intramuscular dose of 2 g
is recommended. In areas of the world where antibiotic
resistance is known to exist, the recommended dose is 4 g in
a single dose in two injection sites.
-
Nitrofurantoin
(Furadantin, Macrodantin)
Action and Use - Nitrofurantoin is
effective against a wide range of gram-positive and
gram-negative organisms, protozoa, and fungi. It is rapidly
and completely absorbed from the intestine but has little or
no systemic effect because it is rapidly excreted through
the kidneys. Its usefulness is limited to urinary tract
infections where the drug attains concentration in the urine
to which most organisms are sensitive. Macrodantin is a
preparation of nitrofurantoin where the crystals are of a
controlled size.
Usual Dose - Nitrofurantoin is used in the
treatment of pyelonephritis, pyelitis, and cystitis. Normal
dose is 50 to 100 mg 4 times daily; it should be given with
meals to increase absorption and minimize gastrointestinal
upset. It is contraindicated where significant renal
impairment exists.
-
Phenazopyridine
(Pyridium)
Action and Use - Although not an
antiinfective, phenazopyridine is included here because it
is used almost exclusively in urinary tract infections.
Phenazopyridine is a urinary tract analgesic indicated for
the symptomatic relief of discomforts arising from
irritation of the lower tract mucosa. Phenazopyridine is
excreted in the urine where it exerts a topical anesthetic
effect on the mucosa of the urinary tract. It is
contraindicated where renal insufficiency exists.
Phenazopyridine imparts a bright red or orange color to the
urine and the patient should be made aware of this fact.
Usual Dose - 200 mg three times daily after
meals.
-
Bacitracin
Action and Use - This bactericide is
effective against a wide variety of organisms. Its mode of
action is the inhibition of bacterial cell wall synthesis.
It is not effective against most aerobic gram-negative
bacilli and is employed locally by topical application in
ointment form.
Antifungals
Antifungal agents inhibit or suppress the growth
systems of fungi, dermatophytes, or Candida. Antifungals have
not been developed to the same degree as antibacterial agents.
Most fungi are completely resistant to the action of chemicals
at concentrations that can be tolerated by the human cell.
Since there are only a few available for internal use, most
antifungal agents are topical. The agents that are available
for systemic use generally produce hepatic or renal dysfunction
or other serious side effects; because of this, systemic
antifungals should be limited to serious or potentially fatal
conditions. When using oral or parenteral antifungal agents,
provide concomitant therapy with topical preparations.
-
Nystatin
(Mycostatin)
Action and Use - Nystatin is primarily used
in the treatment of candidal infections. It is fungicidal
and fungistatic against a wide variety of yeasts and
yeast-like fungi and most often used in the treatment of
candidiasis. It is sometimes used concurrently with
tetracycline to suppress the overgrowth of Candida in the
bowel.
Action and Use - Nystatin is available as a
cream, powder, oral tablets, vaginal tablets, or oral
suspension. The cream or powder should be applied two or
three times daily as indicated by clinical response; one or
two oral tablets three times daily until 48 hours after
clinical cure; vaginal tablets one daily for 2 weeks; and
the oral suspension 2 to 4 ml four times daily held in the
mouth for as long as possible before swallowing.
-
Griseofulvin (Gris-Peg,
Fulvicin)
Action and Use - Griseofulvin is a
fungistatic agent used in the treatment of fungal infections
of the nails, hair, and skin. It is generally reserved for
chronic infections that have not responded to topical
therapy alone. Because treatment may last for several
months, the patient should be instructed to follow the
treatment regimen even though symptoms may abate. In-
clusion of topical therapy is a must for effective
elimination of the infection. Griseofulvin is not indicated
for the treatment of superficial fungal infections that can
be controlled by topical antifungals. Because of its
toxicity, patients should have periodic evaluations of
hepatic and renal function. Griseofulvin is contraindicated
in patients with hepatic dysfunction.
Usage Dose - 500 mg to 1 g daily as either
a single dose or two equally divided doses.
-
Miconazole Nitrate (Monistat)
Action and Use - Miconazole nitrate is a
synthetic antifungal that inhibits the growth of common
dermatophytes. Is is indicated for the treatment of
cutaneous fungal infections and vulvovaginal
candidiasis.
Usage Dose - For topical preparations, the
cream should be applied to the affected area twice daily.
For vaginal infections, either the cream or the suppository
should be inserted daily at bedtime for 7 days.
-
Undecylenic Acid (Desenex)
Action and Use - This is a fatty acid
antifungal, available in ointment, dusting powder, solution,
and spray. It is used primarily in the treatment and
prevention of tinea pedis (athlete's foot) and is often
compounded with zinc to act as an astringent.
For Topical Use - Apply two to four times
daily between the toes and on the affected areas.
-
Tolnaftate (Tinactin,
Aftate)
Action and Use - Tolnaftate was the first
fungicide synthesized. It is effective in the treatment of
superficial fungal infections of the skin. It is indicated
for the topical treatment of tinea pedis (athlete's foot),
tinea corporis (body ringworm), tinea capitis (fungus
infection of the scalp), and tinea versicolor.
Usual Dose - It is for topical use only and
is available in cream, gel, powder, and solution. Only small
quantities are required for effective treatment. Apply twice
daily to the affected area for 2 to 3 weeks.
-
Clotrimazole (Lotrimin,
Mycelex)
Action and Use - This is a broad-spectrum
antifungal that inhibits the growth of pathogenic
dermatophytes, yeasts, and other types of fungus growth,
including Candida albicans. It is indicated for the
treatment of tinea pedis, tinea cruris, tinea corporis, and
candidiasis.
Usual Dose - It is for topical use only. It
is available in cream and solution. It is also available in
a vaginal cream for the treatment of vulvovaginal
candidiasis. Apply twice daily to the affected area for two
weeks. A single daily vaginal application for two weeks is
generally sufficient for cure.
Antiparasitics
Parasitic infections or infestations account for the
largest number of chronic disabling diseases known. They are
especially prevalent in the tropics or subtropics and in lesser
developed countries where overcrowding and poor sanitation
exist. Parasitic infections include protozoal infections, i.e.,
malaria, amebiasis, and to a lesser extent, trichomoniasis;
helminthic infections (intestinal worms), and ectoparasites.
Ectoparasites, although not disabling, are considered a
nuisance and can transmit disease.
-
Lindane (Kwell) (Old name: Gamma Benzene
Hexachloride)
Action and Use - Lindane is a pediculocide
used in the treatment of Pediculosis capitis (head lice) and
Phthirus pubis (crab lice). It is also indicated for
scabies. Use with caution, especially in infants, children,
and pregnant women, since it penetrates human skin and has
the potential for systemic poisoning. This drug is
irritating to the eyes and should be discontinued
immediately if local irritation occurs.
Usual Dose - As a 1 percent cream, lotion,
or shampoo, it is for topical use only. A single application
is usually sufficient to kill parasites and their eggs, but
it may be repeated in 7 days.
-
Crotamiton
(Eurax)
Action and Use - This is a scabicide
indicated for the treatment of scabies (Sarcoptes scabiei);
it also has an antipruitic effect. Keep away from the eyes
and mouth, and do not apply to inflamed skin.
Usual Dose - For topical use only, it is
available in a 10 percent cream or lotion. Thoroughly
massage into the skin of the whole body from the chin down
for scabies treatment. A second application is often
advisable in 24 hours.
-
Metronidazole (Flagyl)
Action and Use - Metronidazole is
effective in the treatment of all forms of amebiasis. It is
also used as a trichomonacide.
Usual Dose - For amebiasis, give 500 to
750 mg three times daily for 5 to 10 days. For
trichomoniasis, give 2 g as a single dose or 250 mg three
times daily for 7 days. Take with food or milk. NOTE: DO NOT
DRINK ANY ALCOHOLIC BEVERAGES; IT MAY CAUSE A "DISULFRAM"
REACTION. Metronidazole is contraindicated in pregnant women
during the first trimester.
-
Chloroquine Phosphate
(Aralen)
Action and Use - Chloroquine phosphate is
the drug of choice in the treatment of acute malarial
attacks and severe disease and in the prevention and
suppression of malaria in endemic areas.
Usual Dose - It is generally administered
once a week while in an endemic area as a prophylactic
agent.
-
Primaquine Phosphate
Action and Use - Primaquine phosphate is
the drug of choice for the prevention or relapse of malaria
caused by P. vivax, and P. ovale. Primaquine phosphate is
contraindicated in G-6-PD deficient personnel as it may
result in hemolytic anemia.
Usual Dose - Primaquine phosphate is most
commonly used as a terminal prophylaxis, i.e., it is given
for 14 days after leaving an endemic area.
-
Fansidar
(Sulfadoxine and Pyrimethamine)
Action and Use - Fansidar is used in the
curative treatment of strains of malaria that are resistant
to chloroquine phosphate. It is also used as a prophylaxis
in endemic areas.
Usual Dose - For the curative treatment, 2
or 3 tablets followed by two weeks of primaquine phosphate
to prevent relapse. For the prophylactic treatment, one
tablet weekly beginning two days prior to arrival in an
endemic area and six weeks after leaving the area followed
by a regimen of primaquine phosphate.
-
Mebendazole (Vermox)
Action and Use - Mebendazole is effective
in treating infestations of hookworm, roundworm, pinworm,
and whipworm.
Usual Dose - For pinworms, a single 100 mg
tablet is generally sufficient to effect cure. For
whipworms, roundworms, and hookworms, a 100 mg tablet
morning and evening for three consecutive days.
-
Pyrantel Pamoate
(Antiminth)
Action and Use - This is regarded as the
drug of choice for pinworm and roundworm infections.
Usual Dose - A single dose of 1 ml (50 mg)
per pound body weight. It maybe administered without regard
to ingestion of food or time of day.
-
Thiabendazole
(Mintezol)
Action and Use - Thiabendazole is a
vermacide used to destroy pinworms, roundworms, threadworms,
hookworms, and whipworms. It is not indicated as a
prophylactic agent.
Usual Dose - The dosage is based on the
patient's weight. For persons over 150 pounds, 1.5 g two
times daily for two days. For persons under 150 pounds,
dosage is 10 mg per pound two times daily. The maximum daily
dosage is 3.0 g.
-
Pyrvinium Pamoate (Povan)
Action and Use - Pyrvinium pamoate is
indicated in the treatment of pinworms. To avoid undue
concern, the patient should be informed that the drug will
stain a bright red and stools will be a bright red.
Usual Dose - Pyrvinium pamoate is
administered in a single dose of 5 mg/kg body weight up to a
maximum of 7 tablets of 50 mg each.
Laxatives
Laxatives are drugs that facilitate the passage and
elimination of feces from the colon and rectum. They are
indicated for the treatment of simple constipation and to clean
the intestine of any irritant or toxic substances (catharsis).
Laxatives may also be used to soften painfully hard stools and
to lessen straining of certain cardiac patients when
defecating. They are contraindicated in certain inflammatory
conditions of the bowel, bowel obstruction, and abdominal pain
of unknown origin, and should not be used in the presence of
nausea and vomiting. Laxatives are classified as irritant,
bulk, emollient, or stool softeners. Frequent or prolonged use
of any laxative may result in dependence.
-
Mineral Oil
Action and Use - Mineral oil is an
emollient laxative used to lubricate the fecal mass. It is
often used in combination with an irritant agent such as
phenophthalein.
Usual Dose - 15 to 45 ml at bedtime.
-
Glycerin Suppositories NF
Action and Use - These are widely used in
children. They promote peristalsis through local irritation
of the mucous membrane of the colon.
Usual Dose - Available in adult and
children sizes. Insert 1 suppository rectally as needed.
Retain for 15 minutes; it does not need to melt to produce
laxative action.
-
Bisacodyl (Ducolax)
Action and Use - Bisacodyl is a relatively
non-toxic irritant cathartic that reflexively stimulates the
colon on contact. It usually produces softly formed stools
in 6 to 12 hours and is normally taken at bedtime. It is
often used as a preparatory agent prior to some surgeries
and radiological examinations.
Usual Dose - 10 to 30 mg in one dose for
adults. It is available in tablets and suppositories.
-
Magnesium Citrate (Citrate of Magnesia)
Action and Use - Magnesium citrate is a
saline irritant laxative that also inhibits the absorption
of water from the intestine. It is preferred by radiology
departments for use prior to special x-rays.
Usual Dose - 200 ml in one dose is the
official recommendation. Magnesium citrate is most often
provided to the patient in a kit containing 10 fluid ounces
of magnesium citrate, 2 tablets of phenophthalein (a contact
irritant) and a suppository of either glycerin or
bisacodyl.
-
Psyllium Hydrophilic Mucilloid (Metamucil)
Action and Use - This is a bulk laxative
that works by absorbing water. The effect occurs within 12
to 72 hours. It is provided as a dry powder that is stirred
into water or fruit juice. Drink immediately upon mixing
while the material is in suspension.
Usual Dose - One rounded teaspoonful
stirred or mixed with a glass of cool liquid or juice one to
three times daily.
-
Ducosate Calcium (Surfak)
Action and Use - Ducosate calcium is a
stool softener that promotes water retention in the fecal
mass.
Usual Dose - 240 mg daily. For children,
give up to 100 mg daily.
-
Ducosate Sodium (Colace)
Action and Use - This drug has the same
action as ducosate calcium.
Usual Dose - Adult dose ranges from 50 to
240 mg daily.
Antidiarrheals
-
Kaolin Mixture with Pectin
(Kaopectate)
Action and Use - Kaolin mixture with pectin
is used in the symptomatic treatment of diarrhea. The pectin
portion absorbs excess fluid and consolidates the stool. The
kaolin portion adsorbs irritants and forms a protective
coating on the intestinal mucosa.
Usual Dose - 30 ml after each bowel
movement.
-
Diphenoxylate Hydrochloride
(Lomotil)
Action and Use - Diphenoxylate
hydrochloride is used for the symptomatic treatment of
diarrhea. It works by direct action on the smooth muscles in
the intestine reducing peristalsis and intestinal motility.
Because diphenoxylate is a chemical analog of meperidine
hydrochloride, it is classed as a schedule V narcotic. To
prevent abuse, a sub-therapeutic amount of atropine is
added.
Usual Dose - 1 or 2 tablets four times
daily until symptomatic control is achieved, then the dose
is reduced.
Diuretics
The kidney is the primary organ that excretes
water-soluble substances from the body. Diuretics are agents
that increase the rate of urine formation. The term diuresis
has two separate connotations: one refers to the net loss of
solute and water, the other to the increase in volume per se.
Sometimes maintenance of an adequate urine volume is
justification for using diuretics. The most important
indication is for the production of a negative extracellular
fluid balance. Diuretics are useful in the treatment of
hypertension, edematous conditions, i.e., congestive heart
failure, and acute pulmonary edema.
-
Hydrochlorothiazide
(Esidrix, Oretic, Hydrodiuril)
Action and Use - Hydrochlorothiazide is
used for edema associated with congestive heart failure and
other edematous conditions. It is also used in the
management of hypertension as the sole agent or in
combination with other antihypertensive agents. It works by
inhibiting the reabsorption of sodium and chloride in the
renal tubules.
Usual Dose - For edema, give 25 to 200 mg
daily. For hypertension, give 25 to 100 mg daily, depending
on the patient's response. In many cases, potassium
supplements may be indicated.
-
Chlorthalidone (Hygroton)
Action and Use - This drug's use is the
same as hydrochlorothiazide.
Usual Dose - Given as a single dose with
food in the morning. For edema, give 100 mg daily or on
alternate days, depending upon the patient. For
hypertension, a dosage above 100 mg a day does not normally
increase effectiveness. Supplemental potassium should be
taken.
-
Furosemide
(Lasix)
Action and Use - A potent diuretic,
furosemide acts on the proximal and distal renal tubules and
on the loop of Henle to promote diuresis by inhibiting the
reabsorption of sodium and chloride. It is indicated in the
treatment of edema associated with congestive heart failure,
cirrhosis of the liver, and renal disease. It is
particularly useful when greater diuretic potential is
desired and may be used in the treatment of hypertension
alone or in combination with other antihypertensive
agents.
Usual Dose - Dosage is individualized to
the patient's needs and responses. For edema, give 20 to 80
mg as a single dose. For hypertension, initially give 40 mg
twice daily, which is adjusted according to response. Other
hypertensive agents may be added. As blood pressure falls,
reduce the dose. Supplemental potassium should be taken.
-
Acetazolamide
(Diamox)
Action and Use - Although classified as a
diuretic, the primary indication for this drug is the
treatment of glaucoma to reduce intraocular pressure.
Usual Dose - 250 mg to 1 g per day, usually
in divided doses.
-
Triamterene and Hydrochlorothiazide (Dyazide)
Action and Use - This combination of a
potassium sparing (Triamterene) and potassium depleting
diuretic is often more effective than either drug alone. It
has the same indications as hydrochlorothiazide.
Dose Use - 1 to 2 capsules twice daily
after meals. Supplemental potassium is NOT generally
indicated.
Non-Narcotic Analgesics and
Antipyretics
Analgesics are drugs that relieve pain without
producing unconsciousness or impairing mental capacities. Many
of these drugs also have an antipyretic and/or an
anti-inflammatory effect. Antipyretics are drugs that lower
increased body temperatures. Included in this group are the
nonsteroidal anti-inflammatories.
-
Aspirin (ASA, Cama,
Ascriptin, Ecotrin, Easprin)
Action and Use - Aspirin is still the most
economical analgesic, antipyretic, and anti-inflammatory
agent available. Some preparations have an antacid-type
buffer to assist in the reduction of gastric irritation. It
is an analgesic for mild to moderate pain and an effective
antipyretic. Aspirin is also indicated for various
inflammatory conditions, such as rheumatoid arthritis,
bursitis, etc.
Usual Dose - For analgesic and antipyretic
purposes, give 325 to 650 mg every 4 hours as needed. For
anti-inflammatory purposes, give up to 5.2 g per day in
divided doses with food or milk. NOTE: Aspirin is
contraindicated in peptic ulcer disease. It acts as a
gastric mucosal irritant and has an anticoagulant
effect.
-
Acetaminophen (Tylenol)
Action and Use - This drug is similar to
aspirin, but it has no anti-inflammatory action. It is
available as tablets, elixir, drops, or capsules and is
useful in aspirin sensitive patients.
Usual Dose - 300 to 650 mg every 4 hours
and up to 1 g four times daily, not to exceed 4 g per
day.
-
Ibuprofen (Motrin)
Action Use - Ibuprofen is indicated for the
relief of mild to moderate pain, including headaches and
menstrual cramps. It is also used as an anti-inflammatory
agent in the treatment of arthritis, tendinitis, bursitis,
etc. It is not recommended in the third trimester of
pregnancy, gastrointestinal bleeding, or renal
impairment.
Usual Dose - Do not exceed 2.4 g per day.
For mild to moderate pain, give 400 mg every 4 to 6 hours as
needed. For anti-inflammatory use, give 300 to 600 mg three
or four times daily as needed. It may be taken with food or
milk.
-
Naproxen Sodium (Anaprox)
Action and Use - Naproxen sodium was
developed as an analgesic because it is more rapidly
absorbed than naproxen (Naprosyn), a non-steroidal
anti-inflammatory with analgesic and antipyretic properties.
It is indicated for the relief of mild to moderate pain and
for the treatment of primary dysmenorrhea, rheumatoid
arthritis, osteoarthritis, tendinitis and bursitis, and
acute gout. Its effects are similar to aspirin and
indomethacin but with less toxic gastrointestinal side
effects; however, it is not indicated for patients with a
history of gastrointestinal disease, especially those with a
propensity for peptic ulcer disease.
Usual Dose - Two tablets initially then one
tablet every 6 to 8 hours as required for mild to moderate
pain but not to exceed 5 tablets daily. For long term
treatment of arthritis, one tablet twice daily for two to
four weeks.
-
Indomethacin (Indocin)
Action and Use - Indomethacin is a potent
anti-inflammatory agent with antipyretic and analgesic
properties. Because it may cause side effects, it should be
reserved for cases of chronic rheumatoid arthritis,
osteoarthritis, or acute gout.
Usual Dose - 25 to 50 mg two to three times
daily not to exceed 200 mg daily.
-
Tolmetin Sodium
(Tolectin)
Action and Use - Tolmetin sodium has the
same indications, contraindications, and uses as
indomethacin.
Usual Dose - 400 mg three times daily
initially, then adjusted to patient response but not to
exceed 2000 mg daily.
-
Sulindac (Clinoril)
Action and Use - Sulindac has the same
indication, contraindication, and uses as indomethacin and
tolmetin sodium but is longer lasting.
Usual Dose - 150 to 200 mg twice daily with
food.
-
Phenylbutazone (Butazolidine)
Action and Use - Along with its anti-
inflammatory properties, phenylbutazone is regarded as a
potent analgesic for relief of the pain of rheumatoid
arthritis and associated condition. Because of its high
incidence of toxic side effects, it is recommended only for
patients who do not respond to less toxic drugs. It is also
used to relieve the symptoms of acute gouty arthritis when
less conservative measures are not effective.
Usual Dose - Initially, 300 to 600 mg daily
in three or four equally divided doses with food or milk.
The dosage is adjusted to the lowest level to receive
favorable results. If favorable results are not obtained in
7 to 10 days, treatment with phenylbutazone should be
discontinued.
Central Nervous System -
Stimulants
Certain drugs stimulate the activity of various
portions of the central nervous system (CNS). Chapter 21 of the
Manual of the Medical Department (MANMED) is explicit as to the
usage of these drugs in the Navy. Primary indications for this
class of drugs are narcolepsy, hyperkinesis, and attention
deficit disorders in children. Central nervous system
stimulants are generally contraindicated in patients with
hypertension, arteriosclerosis, symptomatic cardiovascular
disorders, agitated states, glaucoma, or history of drug
abuse.
-
Methylphenidate Hydrochloride (Ritalin)
Action and Use - This drug is indicated for
use in hyperkinetic children and children with attention
deficit disorders. In children, this drug acts as a central
nervous system depressant. It is also indicated for
narcolepsy in adults.
Usual Dose - In children, start with small
doses, usually 5 mg, and then increase the dosage at a rate
of 5 to 10 mg weekly. The doses are given before breakfast
and lunch. The average dose for adults is 20 to 30 mg per
day, which is given 30 to 45 minutes before meals. Adults
with narcolepsy should take the last dose before 6 p.m.
NOTE: Methylphenidate hydrochloride therapy should be
reevaluated at specific intervals as determined by the
physician. Dosage should be individualized to fit the needs
of each patient.
-
Dextroamphetamine Sulfate (Dexedrine)
Action and Use - Dextroamphetamine is
primarily indicated for narcolepsy. Because of its anorectic
effect, it is occasionally used to treat exogenous obesity
as an adjunct to diet therapy.
Usual Dose - 5 to 60 mg daily in divided
doses.
Central Nervous System -
Depressants
This large group of drugs ranges in depressive action
from mild sedation to deep coma, differing mainly in rapidity,
degree, and duration of action. Many of the central nervous
system depressants are scheduled medications. Chapter 21 of
MANMED describes requirements for control, custody, and
accountability of all controlled substances. Any of these
agents may, in sufficient doses, cause respiratory depression.
Any use of alcohol should be avoided with any of these
medications. NOTE: Barbiturates may be habit forming.
The barbiturates are a widely used group of CNS
depressants that have the same general action. They are used
mainly as sedative-hypnotics, anticonvulsants, anesthetics for
short anesthesia, and they may be used in combination with
analgesics to potentiate their analgesic effect.
-
Phenobarbital (Luminal)
Action and Use - Phenobarbital is a long
lasting barbiturate frequently used in the treatment of
convulsive seizure disorders; this is the drug of choice in
petit mal epilepsy. It is also used as a hypnotic or
sedative.
Usual Dose - The hypnotic dose is 50 to 100
mg daily; the sedative dose is 15 to 32 mg in divided
doses.
-
Pentobarbital (Nembutal)
Action and Use - This barbiturate is
indicated for short-term treatment of insomnia; it is also
used as a preanesthetic medication.
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