Standard Dosing for Amoxicillin
Amoxicillin dosing depends on the infection type, severity, patient age, weight, and kidney function, but typical adult schedules are 500 mg every 8 hours (3 times daily) or 875 mg every 12 hours (2 times daily). For children, it's often based on weight at 20-90 mg/kg/day divided into 2-3 doses.[1][2]
How It Varies by Infection Type
- Ear, throat, or sinus infections: Usually 250-500 mg every 8 hours or 875 mg every 12 hours for 10 days.
- Urinary tract infections: 500 mg every 12 hours for 3-7 days.
- Dental infections: 500 mg every 8 hours for 5 days.
- H. pylori treatment: Often 1 g every 12 hours with other drugs for 10-14 days.
Shorter courses (e.g., 3 days for some UTIs) exist for mild cases.[1][3]
For Children and Special Cases
Kids under 40 kg get 20-45 mg/kg/day split into 2-3 doses; severe infections may need up to 90 mg/kg/day. Newborns or kidney-impaired patients require adjusted, less frequent dosing to avoid buildup.[2][4] Always measure liquid forms precisely.
Why Frequency Matters and What Happens If You Miss
Every 8-hour dosing keeps steady blood levels against bacteria. Twice-daily suits convenience but may underdose resistant strains. Take missed doses ASAP unless near the next one—don't double up. Finish the full course to prevent resistance.[1][3]
Common Side Effects and Precautions
Diarrhea, nausea, or rash occur in 5-10% of users. Rare allergic reactions need immediate medical attention. Avoid if penicillin-allergic; interacts with warfarin or birth control.[2][4] Consult a doctor or pharmacist for your prescription label, as generics match branded Amoxil.
Sources
[1]: Drugs.com - Amoxicillin Dosage
[2]: MedlinePlus - Amoxicillin
[3]: Mayo Clinic - Amoxicillin
[4]: FDA Label - Amoxicillin