(see also: penicillin family)
Discussion
- combination of clavulanic acid and amoxicillin (augmentin - 250 or 500 mg of amoxicillin plus 125 mg of clavulanic acid) provides oral preparation with enhanced activity against beta-lactamase-producing strains of Staph, Branhamella catarrhalis, H. influenza, N gonorrhoeae, and bacteroides;
- oral administration of amoxicillin and clavulanic acid (every 8 hours) is effective for treatment of human-bite infections and animal-bite infections in which Pasturella multocida, streptococci, staphylococci, anaerobes, and Eikenella corrodens are potential etiologic agents;
- for beta lactamase producing H. influenza, Staph aureus, E. coli, Klebsiella, Enterobacter sp.;
- most beta-lactamase-producing strains of E. coli, Proteus mirabilis, and Klebsiella species will be susceptible only to concentrations of combination present in urine;
Dosing:
- adult dosing:
- 250-500 mg as amoxicillin PO q8hr;
- Extended release (XR) 1000 mg q 12; (see discussion - MedicineNet.com)
- do not substitute two 250mg tab for one 500mg because an over dose of clavulic acid may occur;
- note infections of lower respiratory tract: 500mg q8hr;
- infections of ear, nose, throat, GU, skin, soft tissues: 250mg q8h for 7-10 days;
- acute uncomplicated GC: 3gm PO (single dose) plus probenicid 1gm PO (single dose) and tetracycline 500mg PO qid for 7 days;
- note prophylaxis of bacterial endocarditis: 3gm PO 1hr before procedure and 1.5gm PO 6hrs later;
- pediatric dosing:
- 20-40 mg/kg/24hrs PO q8hr x 10 days;
- supplied in susp 125, 250 mg/5 cc;
- dosing in renal insufficiency:
- dose for 70 kg adult (gm/dosing interval in hours)
- CrCl: >80: 0.25-0.5/8;
- CrCl: 50-79: 0.25-0.5/8;
- CrCl:30-49:0.25-0.5/8;
- CrCl:10-29: 0.25-0.5/12;
Cautions:
- will interact w/:
- allopurinol (increase frequency of rash)
- aminoglycosides, oral anticoagulants (increase PT);
- Oral contraceptives (decrease effectiveness)