Amoxicillin is typically taken either twice a day (every 12 hours) or three times a day (every 8 hours), depending on the infection being treated and the dose your provider prescribed. The drug stays at effective levels in your bloodstream for up to 8 hours after a single dose, which is why spacing it evenly throughout the day matters more than the exact clock time.
Common Dosing Schedules for Adults
Most adult prescriptions for amoxicillin fall into one of two patterns: twice daily or three times daily. Twice-daily dosing usually means taking 500 mg to 1,000 mg every 12 hours. Three-times-daily dosing typically means 250 mg to 500 mg every 8 hours. The schedule your provider chooses depends on the type and severity of the infection.
For strep throat, the CDC recommends either 1,000 mg once daily or 500 mg twice daily for 10 days. For sinus infections, ear infections, and urinary tract infections, twice- or three-times-daily schedules are standard. In more serious sinus infections with high fever or other risk factors, doses can go up to 2,000 mg twice daily using extended-release tablets.
The usual maximum for a standard amoxicillin tablet is 875 mg to 1,000 mg per dose. Total daily intake generally caps at around 2,000 mg for most infections, though certain situations push that ceiling higher under medical supervision.
Children’s Dosing Is Based on Weight
Children’s doses are calculated by body weight rather than a fixed number of pills. The standard range is 25 to 50 mg per kilogram of body weight per day, split into two or three doses. For tougher infections like resistant ear infections, providers may prescribe a higher range of 80 to 90 mg per kilogram per day. This is why pediatric amoxicillin comes as a liquid suspension, making it easier to measure precise amounts.
For strep throat in children, the dosing mirrors the adult approach: 50 mg per kilogram once daily (up to 1,000 mg) or 25 mg per kilogram twice daily (up to 500 mg per dose), both for 10 days.
Why Even Spacing Matters
Amoxicillin has a half-life of about one hour, meaning your body clears half the drug from your blood roughly every 60 minutes. Despite that short half-life, detectable levels remain in the bloodstream for up to 8 hours after a single oral dose. Evenly spacing your doses keeps the drug above the concentration needed to kill bacteria for as much of the day as possible.
If you’re on a twice-daily schedule, aim for roughly 12-hour gaps, such as 8 a.m. and 8 p.m. For three times daily, every 8 hours works well, like 7 a.m., 3 p.m., and 11 p.m. You don’t need to hit the exact minute, but try to stay within an hour of each target time. Uneven gaps can let bacteria recover between doses, which makes the antibiotic less effective and can contribute to resistance.
Taking It With or Without Food
Amoxicillin absorbs equally well whether you eat or not. A crossover study comparing 500 mg doses in fasting and fed subjects found nearly identical peak blood levels (8.9 vs. 8.8 micrograms per milliliter) and similar total absorption. So from an effectiveness standpoint, meals don’t matter.
That said, taking it with a small snack or meal can help if the medication bothers your stomach. This is especially useful for children or anyone prone to nausea. You won’t lose any of the drug’s effectiveness by pairing it with food.
The One-Time Dental Dose
There’s one situation where amoxicillin is taken as a single dose rather than a multi-day course. People at high risk for heart valve infections (infective endocarditis) are sometimes prescribed 2,000 mg of amoxicillin as a one-time dose, taken 30 to 60 minutes before an invasive dental procedure. This applies only to specific high-risk patients, not to everyone getting dental work.
What to Do if You Miss a Dose
If you realize you missed a dose and it’s not close to the time for your next one, take it as soon as you remember. If it’s nearly time for the next scheduled dose, skip the missed one and get back on your regular schedule. Don’t double up to compensate. Taking two doses at once increases the risk of side effects like diarrhea and nausea without meaningfully improving the drug’s effectiveness.
Finishing the Full Course
Most amoxicillin courses run 7 to 10 days, with strep throat consistently requiring the full 10 days. It’s common to feel better within two or three days, but stopping early gives surviving bacteria a chance to regrow, potentially causing the infection to come back stronger or harder to treat. The schedule your provider gave you reflects how long it takes to fully clear that particular type of infection, not just to reduce symptoms.