AUGMENTIN '250'
Clinical safety rating: caution
Comprehensive clinical and safety monograph for AUGMENTIN '250' (AUGMENTIN '250').
Amoxicillin inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), disrupting peptidoglycan cross-linking. Clavulanate is a beta-lactamase inhibitor that irreversibly binds to beta-lactamases, preventing hydrolysis of amoxicillin.
| Metabolism | Amoxicillin undergoes partial hepatic metabolism; clavulanate is extensively metabolized in the liver. Both are primarily excreted renally. |
| Excretion | Renal: ~50-70% as amoxicillin, ~25-40% as clavulanate unchanged; biliary/fecal: minor (10-15% combined). |
| Half-life | Amoxicillin: 1.0-1.3 hours; clavulanate: 1.0-1.5 hours; prolonged in renal impairment (up to 7 hours for amoxicillin in anuria). |
| Protein binding | Amoxicillin: 17-20%, clavulanate: 22-30%, primarily to albumin. |
| Volume of Distribution | Amoxicillin: 0.3-0.4 L/kg; clavulanate: 0.2-0.3 L/kg, indicating distribution into extracellular fluid and tissues. |
| Bioavailability | Oral: 70-90% for amoxicillin, ~60% for clavulanate; IV: 100%. |
| Onset of Action | Oral: 1-2 hours to therapeutic serum levels; IV: immediate. |
| Duration of Action | 6-8 hours; dosing interval 8-12 hours based on infection severity and renal function. |
One 250 mg amoxicillin/125 mg clavulanate tablet orally every 8 hours for 7-10 days.
| Dosage form | TABLET |
| Renal impairment | CrCl 10-30 mL/min: 250 mg amoxicillin every 12 hours; CrCl <10 mL/min: 250 mg amoxicillin every 24 hours; hemodialysis: 250 mg amoxicillin after each dialysis session. |
| Liver impairment | Child-Pugh A (mild): no adjustment; Child-Pugh B (moderate): use with caution, reduce dose or increase interval; Child-Pugh C (severe): avoid use. |
| Pediatric use | Based on amoxicillin component: 20 mg/kg/day in divided doses every 8 hours for mild-to-moderate infections; 40 mg/kg/day in divided doses every 8 hours for severe infections (max 1.5 g/day). |
| Geriatric use | Assess renal function; adjust dose based on creatinine clearance; monitor for adverse effects such as diarrhea and rash. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for AUGMENTIN '250' (AUGMENTIN '250').
| Breastfeeding | Excreted in breast milk in low concentrations. M/P ratio not established. Considered compatible with breastfeeding; monitor infant for diarrhea, rash, or candidiasis. |
| Teratogenic Risk | FDA Pregnancy Category B. Studies in animals have not demonstrated fetal risk. No adequate well-controlled studies in pregnant women. Avoid use in first trimester if possible; caution in second and third trimesters. No known teratogenicity. |
| Fetal Monitoring |
■ FDA Black Box Warning
None
| Common Effects | Vomiting Nausea Diarrhea Mucocutaneous candidiasis |
| Serious Effects |
["History of hypersensitivity to penicillins or cephalosporins","Previous cholestatic jaundice or hepatic impairment with amoxicillin-clavulanate"]
| Precautions | ["Severe hypersensitivity reactions including anaphylaxis","Clostridium difficile-associated diarrhea","Hepatic dysfunction (more common in elderly or prolonged use)","Risk of superinfection with prolonged therapy"] |
| Food/Dietary | Take with food to minimize gastrointestinal upset and improve absorption. Avoid high-fat meals as they may delay absorption. No specific food avoidance required. |
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| Monitor maternal renal function and signs of hypersensitivity. Fetal monitoring not specifically required. |
| Fertility Effects | No studies on fertility effects in humans. Animal studies show no impairment of fertility. |
| Clinical Pearls | Augmentin '250' contains amoxicillin 250mg and clavulanate 125mg per 5mL suspension. Clavulanate inhibits β-lactamase, extending amoxicillin's spectrum to include β-lactamase-producing strains of H. influenzae, M. catarrhalis, and S. aureus (not MRSA). Administer every 12 hours with food to reduce GI upset and enhance absorption. Shake suspension well before use; refrigerate suspension to maintain potency. Not effective against MRSA or Pseudomonas. Monitor for diarrhea, rash, and hepatotoxicity (rare but serious). Dose adjustment required in renal impairment (CrCl <30 mL/min). |
| Patient Advice | Take this medication exactly as prescribed, every 12 hours, with a meal or snack. · Shake the suspension well before each dose and measure with the provided device. · Store the suspension in the refrigerator; discard after 10 days. · Complete the full course of treatment even if you feel better. · Inform your doctor if you develop severe diarrhea, rash, or yellowing of skin/eyes. · Do not use if you are allergic to penicillins or cephalosporins. · Check with doctor before use if you have kidney disease or are taking blood thinners. |