Overview and Key Takeaways
Strep throat is a bacterial infection caused by group A Streptococcus. Amoxicillin is a first-line treatment because it is effective, affordable, and convenient. Typical adult dosing is 500 mg twice daily or 875 mg once daily for 10 days, while children often receive a weight-based dose of about 45 mg/kg/day divided twice daily for 10 days. Completing the full course helps prevent complications and reduces antibiotic resistance. This guide explains standard doses, adjustments, safety considerations, and when to contact a clinician, based on current medical guidance.
What Is Strep Throat and Why Treatment Matters
Strep throat is caused by group A Streptococcus bacteria. Without appropriate antibiotic treatment, people remain contagious and risk complications such as acute rheumatic fever or peritonsillar abscess. Amoxicillin is commonly prescribed due to its reliability, tolerability, and convenience. Understanding the prescribed dose, duration, and possible side effects supports safe and effective recovery.
Standard Adult Dosing for Amoxicillin
For non-pregnant adults without advanced kidney impairment, two common regimens are used:
- 500 mg amoxicillin orally twice daily for 10 days
- 875 mg amoxicillin orally once daily for 10 days
Either schedule achieves steady levels that treat strep throat when taken as directed. Some clinicians may use a 7-day course for uncomplicated cases, but 10 days is the traditional standard for strep throat.
Duration and Adherence
Finishing the full 10-day course is important. Even if symptoms improve quickly, stopping early can lead to recurrence and contributes to antibiotic resistance. If swallowing pills is difficult, discuss liquid formulations or alternative options with your clinician.
Adjustments for Kidney Function
Amoxicillin is cleared by the kidneys. Reduced kidney function can require lower doses or longer dosing intervals to avoid accumulation. A clinician will adjust the dose based on estimated glomerular filtration rate (eGFR) and monitor as needed.
Standard Pediatric and Weight-Based Dosing
For children, dosing is primarily weight-based. The widely used target is approximately 45 mg/kg per day divided twice daily for 10 days. Common examples include:
| Weight (kg) | Daily Dose (mg) | Divided BID (mg) | Typical Single Doses (mg) |
|---|---|---|---|
| 10 | 450 | 225 | 225 mg twice daily |
| 20 | 900 | 450 | 450 mg twice daily |
| 30 | 1350 | 675 | 675 mg twice daily |
Available chewable tablets and liquid concentrations vary; always confirm the exact volume or tablet size with a pharmacist to ensure accurate dosing.
Duration for Children
The 10-day course is standard for strep throat in children, even if symptoms improve earlier, to lower the risk of rheumatic fever and other complications.
Pregnancy, Allergies, and Safety Considerations
Amoxicillin is generally considered safe during pregnancy and while breastfeeding when used as prescribed. True penicillin allergy is a key consideration. Symptoms such as hives, swelling, or difficulty breathing require immediate medical attention. Milder rashes may have other causes, but any suspected allergy should be discussed with a clinician before future use. Common side effects include diarrhea, nausea, and rash.
When to Contact a Clinician
Reach out to a clinician if:
- Symptoms worsen or do not improve after 48–72 hours of antibiotics
- You experience severe diarrhea, new rash, or signs of an allergic reaction
- You have persistent fever, trouble swallowing, or swollen neck glands after completing treatment
- You have significant kidney impairment and require dose guidance
These steps support safe use and help ensure the infection is fully resolved.