Cefdinir  (PDF Version)

Antibiotic Class:

Third-Generation Cephalosporin

Antimicrobial Spectrum:

Staphylococcus aureus (methicillin susceptible), Coagulase negative Staphylococci, Streptococcus pneumoniae (penicillin susceptible), Streptococcus spp., Haemophilus influenzae, Moraxella catarrhalis, Neisseria meningitides, Neisseria gonorrhoeae, Enterobacteriaceae, E. coli

Mechanism of Action:

Cephalosporins exert bactericidal activity by interfering with bacterial cell wall synthesis and inhibiting cross-linking of the peptidoglycan. The cephalosporins are also thought to play a role in the activation of bacterical cell autolysins which may contribute to bacterial cell lysis.

Pharmacodynamics:

Cephalosporins exhibit time-dependent killing (T > MIC)

Pharmacokinetics:

Dose of 600mg: Cmax: 2.4 mcg/L; Tmax: 3.2 hour; Half-life: 1.5 hours; Table 10

Adverse Effects:

Hypersensitivity: Maculopapular rash, Urticaria, Pruritis, Anaphylaxis/angioedema, eosinophilia

Hematologic: Hypoprothrombinemia, Neutropenia, Leukopenia, Thrombocytopenia

GI: Diarrhea, C. difficile disease

Renal: Interstitial nephritis

Table 14

Dosage:

PO: 300mg capsule

        Powder for Reconstitution: 125mg/5mL, 250mg/5mL

Dosing in adults:

Acute exacerbation of chronic bronchitis: 300mg PO q12h x 5-10 days OR 600mg PO q24h x 10 days

Community acquired pneumonia: 300mg PO q12h x 10 days

Acute maxillary sinusitis: 300mg PO q12h OR 600mg PO q24h x 10 days

Pharyngitis: 300 mg PO q12h x 5-10 days OR 600mg PO q24h x 10 days

Dosing in pediatrics:

7-14mg/kg/day divided q12-24h

Table 12

Disease state based dosing:

Renal failure:  adults: CrCl < 30mL/min, 300mg q24h

                        children: CrCl < 30mL/min/1.73 m2, 7 mg/kg q24h (up to 300 mg/day)

Hepatic failure:  No dosing changes recommended at this time.

Contraindications/Warnings/Precautions:

Precautions: hypersensitivity to penicillins, history of gastrointestinal disease, particularly colitis, renal impairment, bleeding disorders (like other cephalosporins, cefdinir may be capable of producing hypoprothrombinemia)

Drug Interactions:

Antacids: decreased cefdinir efficacy

Live Typhoid Vaccine: decreased immunological response to the typhoid vaccine

Iron: decreased cefdinir efficacy

Probenecid: increased cefdinir bioavailability

Pregnancy:

Category B: No evidence of risk in humans but studies inadequate.

Monitoring Requirements:

Therapeutic:  Culture and sensitivities, serum levels, signs and symptoms of infection, white blood cell count

Toxic:  Urinalysis, BUN, SCr, AST and ALT, skin rash, Neutropenia and leukopenia, Prothrombin time in patients with renal or hepatic impairment or poor nutritional state, as well as patients receiving a protracted course of antimicrobial therapy, and patients previously stabilized on anticoagulant therapy.

Brand names/Manufacturer:

Omnicef /Abbott