Typical adult dosing is 500–875 mg every 12 hours or 250–500 mg every 8 hours, based on infection type and your prescription.
Amoxicillin dosing isn’t one-size-fits-all. The mg amount hinges on the infection being treated, how severe it is, your age and weight, kidney function, and the product you were given (immediate-release versus special regimens such as H. pylori therapy). The safest path is to match your prescriber’s directions and the pharmacy label on your bottle. This guide explains common amounts, when each schedule is used, and the key caveats that affect how many milligrams you take per dose.
Recommended Amoxicillin Mg Per Dose By Condition
Here’s a plain-English view of common adult regimens used in clinics and urgent care. The numbers below align with major references and product labeling. Duration often ranges from 5 to 10 days unless a special regimen applies.
| Condition | Usual Adult Amount (mg) | Frequency & Typical Duration |
|---|---|---|
| Strep Throat (Group A) | 500 mg | Every 12 hours for 10 days; single-daily 1,000 mg regimens also used in some guidance. |
| Acute Bacterial Sinusitis | 500–875 mg | Every 12 hours for 5–10 days, based on severity and local practice. |
| Otitis Media (Adult) | 500–875 mg | Every 12 hours for 5–10 days; higher end used for more severe symptoms. |
| Bronchitis (When Bacterial) | 500–875 mg | Every 12 hours for 5–7 days, only when a bacterial cause is identified or strongly suspected. |
| Skin/Soft Tissue | 500 mg | Every 8–12 hours for 5–10 days, tailored to site and response. |
| Uncomplicated UTI | 500 mg | Every 8–12 hours; length varies by organism and response. |
| H. pylori (as part of triple therapy) | 1,000 mg | Every 12 hours for 14 days with a PPI and clarithromycin (or other guideline-based combo). |
| Dental Endocarditis Prevention | 2,000 mg (single dose) | Once, 30–60 minutes before the qualifying dental procedure (for eligible patients). |
Why amounts vary: pathogen patterns, tissue penetration, and time-above-MIC targets drive dosing choices. The immediate-release tablet keeps blood levels steady when taken every 8 or 12 hours. Many adults are issued 500 mg or 875 mg tablets because those strengths fit common schedules well. Authoritative consumer guidance on timing, missed doses, and duration is available on the NHS amoxicillin page.
How Dose Schedules Work
Amoxicillin is a time-dependent beta-lactam. The goal is to keep drug levels above the bug’s kill threshold for much of the dosing interval. That’s why the label offers two standard rhythms:
- Every 8 hours (three times daily): often 250–500 mg per dose.
- Every 12 hours (twice daily): often 500–875 mg per dose.
Both reach similar daily totals, but the twice-daily option can be easier to remember. Some infections need higher per-dose mg to hit targets, which is where 875 mg BID shows up.
When Higher Or Lower Mg Makes Sense
Severity And Site
Tougher sites like sinuses or middle ear often push doses toward the higher end. Deeper infections or slow response can extend the days on therapy. Your prescriber weighs these factors against your kidney function and allergy history.
Kidney Function
Amoxicillin clears through the kidneys. Low eGFR leads to drug accumulation if the interval isn’t widened. Many references drop from every 8 hours to every 12–24 hours in advanced impairment, with the mg per dose staying the same or slightly reduced. The FDA label outlines interval changes for severe renal decline and dialysis schedules (hemodialysis can remove the drug between sessions). For product-specific language, see the current US prescribing information.
Strep Throat Nuances
Group A strep regimens run for 10 days to prevent rheumatic fever. Common schedules include 500 mg twice daily or a single daily total of 1,000 mg in some protocols. CDC guidance stresses testing and treatment steps for confirmed cases; see the agency’s strep throat clinical guidance for details on confirmation and therapy length.
Which Tablet Strength Should You Use?
Use the exact strength dispensed by your pharmacy. The most common immediate-release tablet strengths are 500 mg and 875 mg. Capsules and chewables exist at 250 mg and 500 mg, and liquid suspensions support weight-based dosing in children.
Adult Dosing Walkthroughs
Sinus Symptoms With Bacterial Signs
Many adults are issued 875 mg every 12 hours for 5–7 days when a bacterial cause is evident and risk factors support treatment. Shorter courses can work for mild cases; longer courses are common when symptoms run longer or complications arise.
Middle Ear Inflammation (Adult)
Typical starts at 500–875 mg every 12 hours. A reassessment often happens around day 2–3. If pain and fever break early, finish the course as directed to fully clear the infection.
Uncomplicated Urinary Tract Infection
Some regimens use 500 mg every 8–12 hours. Culture results can shift the plan to a different antibiotic if the organism shows resistance.
Skin And Soft-Tissue Infections
Cellulitis that points to streptococci often fits 500 mg every 8–12 hours. Bites or polymicrobial wounds may need combinations or alternative agents.
Weight-Based Amounts For Children
Kids use mg/kg schedules to equalize exposure by body size. The total daily mg per kg then splits into two or three doses. Some common patterns from pediatric summaries and national guidance:
| Pediatric Scenario | Total Daily Amount | Schedule & Days |
|---|---|---|
| Strep Throat (Confirmed) | 50 mg/kg/day (max 1,000 mg/day) | Once daily for 10 days; or 25 mg/kg twice daily for 10 days. |
| Acute Otitis Media | 80–90 mg/kg/day (high dose) | Split q12h for 5–10 days based on age/severity. |
| Sinusitis (When Bacterial) | 45–90 mg/kg/day | Split q12h for 5–10 days; higher end used for higher-risk settings. |
Liquid suspensions allow precise mg/kg amounts. Pharmacists often print the per-dose milligrams and the volume in mL right on the label to prevent mix-ups. If a kid spits part of a dose, do not “double” the next one. Ask your prescriber or pharmacist how to handle partial doses in that scenario.
Timing, Food, And Missed Doses
- With or without food: Either is fine for immediate-release tablets; food can ease stomach upset.
- Set reminders: Spacing matters. Every 12 hours means morning and evening at steady times.
- Missed dose: Take it when remembered unless it’s close to the next one. Don’t take two at once.
- Finish the course: Stopping early can allow the infection to rebound.
When The Label Looks Different From This Guide
Clinical judgment and local resistance patterns shape dosing. Some prescribers raise mg or extend days for slow responders. Others shorten therapy when symptoms resolve quickly and guidelines allow it. Drug labeling also includes special regimens, such as 1,000 mg twice daily for H. pylori with a proton pump inhibitor and a macrolide.
Kidney Dose Adjustments In Plain Terms
If your estimated GFR is low, the amount per dose may stay the same while the interval widens to every 24 hours, or the mg amount drops while the twice-daily rhythm stays. Dialysis patients often take a dose after each session. The exact schedule comes from your prescriber and the product label. For the official language, see the FDA prescribing information.
Common Strengths And Formats
Knowing the tablet or liquid strength helps you translate directions into the mg you swallow each time.
- Tablets: 500 mg, 875 mg (immediate-release).
- Capsules: 250 mg, 500 mg.
- Chewables: 125 mg, 250 mg.
- Suspensions: Commonly 125 mg/5 mL, 250 mg/5 mL, 400 mg/5 mL; pharmacies may reconstitute to different bottle sizes.
Safety Notes That Affect The Mg You Take
Allergy History
Anyone with a serious reaction to penicillins or cephalosporins needs a different plan. Hives, wheezing, or swelling after prior doses are red flags that require medical input before any more tablets are taken.
Drug Interactions
Probenecid raises amoxicillin levels by reducing renal clearance; some protocols pair them for a pharmacokinetic boost, while everyday use should avoid that mix unless directed. Warfarin users may need closer INR checks. Bring your medication list to the visit so dosing reflects the full picture.
Pregnancy And Lactation
Amoxicillin sees wide use during pregnancy and while breastfeeding. Dosing in these settings follows the same infection-based logic, with product labeling and national references guiding adjustments when needed.
Answering The Big Question: How Many Milligrams Should You Take?
Match the mg to your verified diagnosis and the exact schedule printed on your bottle. Adults frequently land on 500 mg every 8–12 hours or 875 mg every 12 hours. Strep throat runs a full 10 days. H. pylori therapy uses 1,000 mg twice daily with companion drugs for 14 days. Kidney issues shift the interval. Children follow mg/kg math. If your label conflicts with what you read online, the label wins.
Quick Reference: Adult Patterns You’ll See On Pharmacy Labels
- “Take one 875 mg tablet by mouth every 12 hours” → common for sinus or ear infections.
- “Take one 500 mg capsule by mouth three times daily” → common across many mild-to-moderate infections.
- “Take two 500 mg tablets (1,000 mg total) every 12 hours with other medicines” → seen in H. pylori triple therapy.
- “Take four 500 mg capsules (2,000 mg total) 1 hour before dental work” → endocarditis prevention in eligible patients.
Evidence And Labels Behind These Numbers
The US label sets core dosing ranges, therapy length for strep to prevent rheumatic fever, and renal timing changes. See the FDA prescribing information. Public-facing dosing and practical use tips are summarized by the NHS amoxicillin guidance, and testing/treatment steps for strep throat are outlined by the CDC clinical page.
What To Do If Things Don’t Improve
If fever, pain, or swelling persists past 48–72 hours on therapy, reach out to your prescriber. Dosing may be correct, yet the bug could be resistant or the diagnosis may need a second look. Never change the mg or shorten the course on your own. If you develop hives, wheeze, facial swelling, severe diarrhea, or a rash with blisters, stop dosing and seek urgent care.
Bottom Line On Picking The Right Mg
Use the mg and schedule that match your diagnosis and your renal status. Adults often take 500–875 mg per dose on an every-12-hours rhythm. Kids use mg/kg math. Strep therapy runs 10 days. H. pylori uses 1,000 mg twice daily with other medicines. When in doubt, follow the pharmacy label and contact your clinic before making any change.