What is the recommended dosage of Amoxicillin (amoxicillin) for the treatment of streptococcal pharyngitis (strep throat)?

From the Guidelines

For strep throat, the recommended dosage of amoxicillin is 50 mg per kilogram of body weight per day, divided into two or three doses, for 10 days, with a maximum dose of 1000 mg per day 1. This dosage is based on the strongest and most recent evidence from the Infectious Diseases Society of America and other reputable sources. The following key points should be considered:

• The dosage for adults is not explicitly stated in the provided evidence, but it can be inferred that the maximum dose of 1000 mg per day can be used for adults, divided into two or three doses.
• It is essential to complete the entire course of antibiotics, even if symptoms improve before the medication is finished, to ensure the infection is completely eliminated and reduce the risk of antibiotic resistance.
• Amoxicillin can be taken with or without food, but taking it with food may help reduce stomach upset.
• Common side effects include diarrhea, stomach upset, and rash. If severe diarrhea, severe rash, or difficulty breathing occur, medical attention should be sought immediately, as these could indicate an allergic reaction.
• Amoxicillin works by inhibiting bacterial cell wall synthesis, causing the bacteria to die, and is effective against Group A Streptococcus, the bacteria that causes strep throat, helping to prevent complications like rheumatic fever. Some key considerations for the treatment of strep throat include:
• The importance of accurate diagnosis to prevent unnecessary antibiotic use and reduce the risk of antibiotic resistance.
• The need to consider patient factors, such as penicillin allergy, when selecting an antibiotic.
• The potential for side effects and the importance of monitoring for these during treatment.
• The importance of completing the full course of antibiotics to ensure effective treatment and prevent complications.

From the FDA Drug Label

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 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 recommended amoxicillin dosage for strep throat is:

• For mild to moderate infections: 500 mg every 12 hours or 250 mg every 8 hours for adults, and 25 mg/kg/day in divided doses every 12 hours or 20 mg/kg/day in divided doses every 8 hours for pediatric patients.
• For severe infections: 875 mg every 12 hours or 500 mg every 8 hours for adults, and 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours for pediatric patients. Treatment should be continued for at least 10 days to prevent the occurrence of acute rheumatic fever 2.

From the Research

Amoxicillin Dosage for Strep Throat

• The recommended course of amoxicillin for strep throat is 10 days 3, 4
• Amoxicillin is equally effective as penicillin and more palatable 4
• Penicillin and amoxicillin are first-line antibiotics for the treatment of strep throat 3, 4, 5
• The choice of antibiotic does not significantly affect the outcome in strep throat, and penicillin or amoxicillin is recommended as the first choice due to the absence of resistance and low cost 5
• For children, amoxicillin or penicillin is recommended when a throat swab is positive for Group A Streptococcus (GAS) pharyngitis 6

Diagnosis and Treatment Guidelines

• Guidelines recommend using clinical decision rules to assess the risk of group A beta-hemolytic streptococcal infection, followed by rapid antigen testing if a diagnosis is unclear, before prescribing antibiotics 3
• Clinical guidelines developed by professional associations can help medical professionals choose among available techniques to diagnose strep throat 7
• Treatment for strep throat seeks to provide symptom relief, shorten the duration of illness, prevent nonsuppurative and suppurative complications, and decrease the risk of contagion, while minimizing the unnecessary use of antibiotics 7