Amoxicillin: what it treats, how to take it, and safety tips

Amoxicillin is a widely used antibiotic for bacterial infections such as ear infections, strep throat, sinusitis, bronchitis, some skin infections, and certain urinary infections. It’s a penicillin-type drug that kills bacteria by stopping their cell wall growth. Used correctly, it clears infections fast and lowers the risk of complications.

Take the medicine exactly as your prescriber tells you. Don’t double doses or stop early because you feel better — stopping early can let bacteria survive and become resistant. If your doctor prescribes a different dose than what you saw online, follow the doctor’s instructions, not internet advice.

Quick Dosage Guide

Typical adult doses for common outpatient infections are 500 mg every 8 hours or 875 mg every 12 hours. Some infections and severe cases need higher or IV doses, which your clinician will decide. Children get doses based on weight; common pediatric ranges are roughly 20–90 mg per kg per day split into two or three doses depending on the illness. If you have kidney problems your provider may lower the dose. If you take a liquid, measure it with the syringe the pharmacy gives — kitchen spoons are inaccurate.

Common Side Effects and When to Seek Help

Mild side effects include nausea, vomiting, and diarrhea. These often pass after the course ends. A new rash can happen; a mild rash may be harmless but a widespread itchy rash, swelling of the face or throat, trouble breathing, or fainting are signs of a serious allergic reaction. Call emergency services if that happens. Also contact your doctor if you have severe, persistent watery diarrhea after treatment — that can be a C. difficile infection and needs care.

Tell your provider if you have had a penicillin allergy or reactions to related antibiotics. Amoxicillin can interact with some drugs, like warfarin or methotrexate, so list all medications and supplements you use. The medicine is commonly prescribed in pregnancy and while breastfeeding, but always check with your clinician about risks and alternatives.

Antibiotic stewardship matters: amoxicillin doesn’t work on viruses. Don’t expect it to help with colds, most sore throats, or flu unless a doctor confirms a bacterial cause. If symptoms don’t improve in 48–72 hours or get worse, call your provider for reassessment.

Buying tips: use licensed pharmacies, require a prescription, and avoid sites that sell antibiotics without verifying a prescription. Keep the medicine in a cool, dry place and follow expiration dates. If you have any doubts — dose, side effects, or interactions — ask a pharmacist or clinician. Proper use keeps you safer and helps antibiotics stay effective for everyone.