Military Obstetrics & Gynecology
Pharmacy

Cephalexin (Keflex, Duricef)

Category:

• Antibiotic

Description:

• Cephalosporin, First Generation

Indications:

• Respiratory tract infections (S. pneumoniae, group A beta-hemolytic streptococci)

• Otitis media (S. pneumoniae, H. influenzae, M. catarrhalis, staphylococci, streptococci)

• Genitourinary tract infections (E. coli, Klebsiella species, Proteus mirabilis)

• Skin, bone, and joint infections (staphylococci, streptococci, Proteus mirabilis)

Contraindications:

• Cross sensitivity with penicillin allergies

Precautions:

• Pregnancy category B

• Use with caution in patients with penicillin allergy (5-10% chance of cross-reactivity)

• Counsel patient to finish all medication to prevent development of resistance

Adverse Reactions (Side Effects):

• Hypersensitivity reactions

• Gastrointestinal: nausea, vomiting, diarrhea

• Vaginitis

Dosage:

• Administered orally (capsules and oral suspension)

• Adults:

  • 250mg every 6 hours (1-4 grams per day in divided doses)

  • Strep pharyngitis, skin and skin structure infections and uncomplicated cystitis in patients >15 years old: 500mg every 12 hours

• Children:

  • Do not exceed adult dosing

  • Otitis media: 75-100mg/kg/day in 4 divided doses

  • Beta-hemolytic streptococcal infections: continue therapy for at least 10 days

  • For oral suspension:  refrigerate, shake well, good for 14 days only