Questions About A High Dosage Of Amoxicillin For A Child With Strep Throat

In our latest question and answer, our pharmacist discusses concerns a reader has regarding their son being prescribed a high dose of amoxicillin.

Question

My son, who weighs 78 lbs, was diagnosed with strep throat on Tuesday. The doctor prescribed 250mg of amoxicillin, four pills twice a day for ten days. This seems like a lot, 2000mg per day!?

Asked by Terra On Mar 04, 2023

Answered by
Medical Content Reviewed By HelloPharmacist Staff

Published Mar 04, 2023
Last updated Apr 26, 2024

Key points

  • Recommended dosing for amoxicillin for strep throat varies slightly by source, but it generally is dosed at 500 mg twice daily or 1,000mg once daily for 10 days.
  • The dose of 2,000mg per day prescribed for your son is high for strep throat, but there may be other factors at play, such as antibiotic resistance. Studies show that high-dose amoxicillin (up to 4 grams daily) can be used successfully for certain conditions (such as difficult-to-treat ear infections).
  • Amoxicillin is generally well-tolerated, and it's recommended to speak to a pharmacist or doctor if there are concerns about the dosage.

Answer

I'm more than happy to answer this question for you! Guidelines do vary slightly on the recommended dose of amoxicillin for the treatment of strep throat (i.e., streptococcal pharyngitis).

One of the most commonly sourced references on dosing is the 'Clinical Practice Guideline for the Diagnosis and Management of Group A Streptococcal Pharyngitis', which can be found in full on the Oxford Academic website. Here is an image of the dosing recommendations for amoxicillin from their guidelines:

Streptococcal Pharyngitis: 2012 Update by the Infectious Diseases Society of America

They recommend the following:

  • 50mg/kg once daily (maximum of 1,000mg per dose) for 10 days OR 25mg/kg (maximum of 500mg/dose) every 12 hours for 10 days.

Your son weighs 78 pounds, which is equivalent to 35.37 kilograms. Following these guidelines would put your son's recommended dosage, based on weight, at:

  • 1,768.5 mg once daily OR 884.25 mg twice daily for 10 days

However, since the guidelines set a maximum dosage of 1,000mg once daily or 500mg twice daily, that would be the recommendation, so yes, the dose you wrote in (2000mg per day) is high.

It's possible the doctor is following other guidelines.

For example, the prescribing information for amoxicillin recommends a higher dose for severe infections (even though this dosing may be a little outdated). The following is an image from the prescribing information showing the recommendation of 45 mg/kg/day in divided doses every 12 hours for severe infections.

Amoxicillin Usual Dose Children Strep

If your doctor was following the above recommendations, the dosage for your child that weights 35.37 kg would be:

  • 1,591mg per day (or 795.82 mg every 12 hours).

So, still, the dosage of 1,000mg twice daily (2,000mg per day total) is high, and higher than the recommended dosing for amoxicillin for treating strep throat.

I will say that there could be other factors in play when it comes to the dosing the doctor is using.

While the maximum FDA-approved dose of amoxicillin is 1,750mg per day, doses as high as 100mg/kg/day (up to 4,000mg per day) have been used 'off-label' for certain infections and certain situations (one example is for difficult to treat ear infections, where 'high-dose' amoxicillin, dosed at 80-90mg/kg/day, has been effective according to several studies).

There are some guidelines too that recommend high-dose amoxicillin for greater effectiveness in infections commonly caused by resistant strains of Streptococcus. It's possible that is going on in your area and the doctor is using a higher dose than usual to overcome said resistance.

At 2000mg per day, your son is taking a dosage of 56.54mg/kg per day. High for strep on most occasions, but certainly within a dosage range that has been used for other infections.

The good news is that amoxicillin is a relatively well-tolerated drug, even at higher dosages. It certainly may cause nausea, diarrhea, and other similar side effects, but they are generally mild and can be helped by taking the drug with food.

I recommend speaking to your pharmacist or doctor if you are concerned about the dosage. There are likely other factors at play that you and I aren't aware of.

Final Words

Summing everything up, I would say that on the surface, yes, the dose prescribed for your son is higher than usual, but it is not out of the dosage range I have seen used in children for other infections.

Thanks for reaching out! Please do so again anytime.

References

  • Clinical practice guideline for the diagnosis and management of group A streptococcal pharyngitis: 2012 update by the Infectious Diseases Society of America, PubMed
  • Amoxil Prescribing Information, AccessFDA
  • High dose amoxicillin: Rationale for use in otitis media treatment failures, PubMed

About the Pharmacist

Dr. Brian Staiger, PharmD

Dr. Brian has been practicing pharmacy for over 13 years and has wide-ranging experiences in many different areas of the profession. From retail, clinical, program development, and administrative responsibilities, he's your knowledgeable and go-to source for all your pharmacy and medication-related questions! Dr. Brian Staiger also has herbalist training and educational certificates in the field of medical ethnobotany. Feel free to send him an email at [email protected]! You can also connect with Dr. Brian Staiger on LinkedIn.

Recent Questions