Otitis media, lower respiratory tract infection, pharyngitis and tonsillitis, urinary tract infection, and skin and skin structure infections due to susceptible organisms
Adults: 250 mg PO q8h, doubled for more severe infections or less susceptible organisms. Children: 20 mg/kg/day PO divided q8h, or 40 mg/kg/day for otitis media and more serious infections, maximum 1 g/day. At least 10 days for beta-hemolytic streptococcal infection.
Contraindications
Known allergy to the cephalosporin group of antibiotics.
Available Forms
250 mg and 500 mg capsules
Mechanism of Action
Bactericidal by inhibition of bacterial cell wall synthesis, as with other cephalosporins. Coverage excludes methicillin-resistant staphylococci, enterococci, Pseudomonas, Enterobacter, indole-positive Proteus, and Serratia, and beta-lactamase-negative ampicillin-resistant Haemophilus influenzae should be treated as resistant despite apparent in vitro susceptibility.
Warnings & Precautions
Cephalosporin and penicillin cross-reactivity: Cross-hypersensitivity among beta-lactams is clearly documented and may occur in up to 10% of patients with a history of penicillin allergy.
Anaphylaxis: Serious acute hypersensitivity may require epinephrine, oxygen, IV fluids, IV antihistamines, corticosteroids, pressor amines, and airway management.
Methicillin-resistant staphylococci: No activity, so this is not a choice when community MRSA is suspected.
BLNAR Haemophilus influenzae: Beta-lactamase-negative ampicillin-resistant strains should be considered resistant despite apparent in vitro susceptibility.
Pseudomembranous colitis: Reported with nearly all antibacterials, mild to life-threatening; consider it in any diarrhea during or after therapy.
Gastrointestinal history: Caution in patients with a history of gastrointestinal disease, particularly colitis.
Positive Coombs test: Reported during cephalosporin therapy and may confound transfusion cross-matching and Coombs testing of newborns.
Renal impairment: Caution with markedly impaired function; dosage adjustment is usually not required, since the half-life in anuria is 2.3 to 2.8 hours.
Cephalosporin-class seizures: Several cephalosporins have been implicated in triggering seizures, particularly in renal impairment when the dose was not reduced.
Superinfection: Prolonged use may result in overgrowth of nonsusceptible organisms.
Interactions: Increased anticoagulant effect reported with oral anticoagulants; probenecid inhibits renal excretion; false-positive urine glucose with Benedict's and Fehling's solutions and Clinitest.
Common Side Effects
Hypersensitivity: About 1.5% of patients, with morbilliform eruption 1 in 100 and pruritus, urticaria, or a positive Coombs test each under 1 in 200.
Serum-sickness-like reaction: Erythema multiforme, rash, and arthritis or arthralgia with or without fever, more often in children and during or after a second course; 0.024% across clinical trials overall and 0.5% in one focused trial.
Severe cutaneous: Stevens-Johnson syndrome, toxic epidermal necrolysis, and anaphylaxis reported rarely; anaphylaxis may be more common with a history of penicillin allergy.
Gastrointestinal: About 2.5% of patients, diarrhea 1 in 70; nausea and vomiting rare, transient hepatitis and cholestatic jaundice rare.
Other: Eosinophilia 1 in 50, genital pruritus or candidiasis about 1 in 50, rare thrombocytopenia and reversible interstitial nephritis.
Pregnancy & Lactation
Pregnancy: Category B. No fetal harm in mice and rats at up to 12 times the human dose or in ferrets at 3 times the maximum human dose; no adequate and well-controlled studies in pregnant women, so use only if clearly needed.
Lactation: Small amounts appear in milk, averaging 0.16 to 0.21 mcg/mL between 2 and 5 hours after a single 500 mg dose; the effect on the nursing infant is unknown.
Pediatric Use
Safety and effectiveness not established under 1 month of age.
Available Forms
Mechanism of Action
Pregnancy & Lactation
Pediatric Use