From the Guidelines
The recommended dose of amoxicillin for strep throat is 50 mg/kg/day, with a maximum of 1000 mg/day, divided into two or three doses, for a duration of 10 days. For example, a 20 kg child would receive about 500 mg per day, which could be given as 250 mg twice daily 1. The 10-day duration is important to complete even if symptoms improve earlier, as this helps prevent complications like rheumatic fever and ensures complete eradication of Group A Streptococcus. Amoxicillin is preferred due to its narrow spectrum, good absorption, and palatability, especially for children. It works by inhibiting bacterial cell wall synthesis, leading to bacterial cell death. If the patient has a penicillin allergy, alternatives include cephalexin (if no anaphylactic reaction history) or macrolides like azithromycin, though resistance to macrolides is increasing in some regions 1.
Some key points to consider when treating strep throat with amoxicillin include:
- The importance of completing the full 10-day course of treatment, even if symptoms improve earlier, to prevent complications and ensure complete eradication of the bacteria 1
- The need to consider alternative treatments for patients with penicillin allergies, such as cephalexin or macrolides like azithromycin 1
- The potential for resistance to macrolides in some regions, which may affect treatment outcomes 1
- The importance of selecting an antimicrobial agent with a narrow spectrum of activity, such as penicillin or amoxicillin, to minimize the risk of selecting for antibiotic-resistant flora 1
From the FDA Drug Label
In some infections, therapy may be required for several weeks. It may be necessary to continue clinical and/or bacteriological follow-up for several months after cessation of therapy. It is recommended that there be at least 10 days’ treatment for any infection caused by Streptococcus pyogenes to prevent the occurrence of acute rheumatic fever. Table 1 ... Ear/Nose/Throat ... Mild/ Moderate 500 mg every 12 hours or 250 mg every 8 hours 25 mg/kg/day in divided doses every 12 hours or 20 mg/kg/day in divided doses every 8 hours Table 1 ... Ear/Nose/Throat ... Severe 875 mg every 12 hours or 500 mg every 8 hours 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours
The dose of amoxicillin per weight for strep throat is:
- Mild/Moderate: 25 mg/kg/day in divided doses every 12 hours or 20 mg/kg/day in divided doses every 8 hours
- Severe: 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours The recommended duration of treatment for strep throat is at least 10 days to prevent the occurrence of acute rheumatic fever 2.
From the Research
Amoxicillin Dosage and Duration for Strep Throat
- The dosage of amoxicillin for strep throat is typically 40-50 mg/kg/day, as indicated in the study 3.
- The duration of amoxicillin treatment for strep throat is usually 10 days, as mentioned in the studies 4 and 3.
- The dosage can be divided into one, two, or three daily doses, with no significant difference in effectiveness between these regimens, according to the study 3.
- Amoxicillin is equally effective as penicillin in treating strep throat, and is often preferred due to its palatability, as stated in the study 4.
Comparison with Other Antibiotics
- Amoxicillin/clavulanate has been compared to clarithromycin and penicillin V in the treatment of strep throat, with amoxicillin/clavulanate showing similar clinical efficacy and better bacteriological efficacy, as reported in the study 5.
- Clarithromycin has been shown to be less effective in eradicating streptococcal infections, particularly in areas with high resistance rates, as mentioned in the study 5.