What is the appropriate dosing of Penicillin (Penicillin) for a child with streptococcal (Strep) pharyngitis in liquid form?

From the Guidelines

For a child with strep pharyngitis, the recommended liquid penicillin dosing is amoxicillin 50 mg/kg once daily (maximum 1000 mg per dose) or 25 mg/kg twice daily (maximum 500 mg per dose) for 10 days, as this regimen has been shown to be effective in eradicating Group A Streptococcus and preventing complications like rheumatic fever 1. The medication should be given for the full 10-day course even if symptoms improve earlier to ensure complete eradication of the bacteria. Some key points to consider when administering this medication include:

• The liquid formulation should be refrigerated after reconstitution and shaken well before each dose.
• If the child has a penicillin allergy, alternatives include cephalexin, azithromycin, or clindamycin, though these would require different dosing regimens 1.
• Penicillin remains the first-line treatment because Group A Streptococcus has not developed resistance to it, and it has a narrow spectrum of activity which reduces the risk of developing antibiotic resistance. It's also important to note that the diagnosis of strep pharyngitis should be established through accurate testing, as the signs and symptoms of GAS and nonstreptococcal pharyngitis can overlap, making clinical diagnosis alone unreliable 1. The IDSA guidelines recommend that physicians exclude the diagnosis of GAS pharyngitis to prevent inappropriate administration of antimicrobials to large numbers of patients with nonstreptococcal pharyngitis 1. In terms of specific dosing, the guidelines recommend the following for patients without penicillin allergy:
• Penicillin V, oral: 250 mg two or three times daily for children, 250 mg four times daily or 500 mg twice daily for adolescents and adults, for 10 days 1.
• Amoxicillin, oral: 50 mg per kg once daily (maximum = 1,000 mg) or 25 mg per kg twice daily (maximum = 500 mg), for 10 days 1.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION The dosage of penicillin V potassium tablets should be determined according to the sensitivity of the causative microorganisms and the severity of infection, and adjusted to the clinical response of the patient The usual dosage recommendations for adults and children 12 years and over are as follows: Streptococcal Infections Mild to moderately severe - of the upper respiratory tract and including scarlet fever and erysipelas: 125 to 250 mg (200,000 to 400,000 units) every 6 to 8 hours for 10 days

The recommended dosing for a child with strep pharyngitis is 125 to 250 mg (200,000 to 400,000 units) every 6 to 8 hours for 10 days. However, the label does not provide information on dosing for children under 12 years old, and it does not specify the dosing in liquid form. 2

From the Research

Penicillin Dosing for Children with Streptococcal Pharyngitis

• The recommended first-line therapy for streptococcal pharyngitis is a 10-day course of penicillin V, usually given 2 or 3 times per day 3.
• Penicillin V is typically administered at a dose of 50,000 IU/kg (30 mg/kg) per day, divided into 2 or 3 doses 3, 4.
• For children with streptococcal pharyngitis, a 10-day course of penicillin V is effective in eradicating the infection and preventing complications such as acute rheumatic fever 3, 5.
• Alternative antibiotics, such as amoxicillin, may also be effective in treating streptococcal pharyngitis in children 6.
• The use of a clinical diagnostic score, followed by a rapid test if the score is intermediate, can help restrict antibiotics to patients with pharyngitis due to group A streptococci 7.

Liquid Form Penicillin Dosing

• There is no specific information provided in the studies regarding the dosing of liquid form penicillin for children with streptococcal pharyngitis.
• However, it is likely that the dosing of liquid form penicillin would be similar to that of oral penicillin V, with the dose adjusted based on the child's weight and age.

Considerations for Treatment

• The choice of antibiotic and dosing regimen should be based on the individual child's needs and medical history 3, 5.
• It is essential to complete the full course of antibiotic therapy to ensure effective treatment and prevent complications 3, 5.
• Palatability is an important consideration when prescribing antibiotics to children, and some antibiotics may be more acceptable to children than others 3.