Pediatric Doxycycline Dosing for Lyme Disease Prophylaxis

Eligibility Criteria and Prophylaxis

For children ≥8 years old, a single dose of doxycycline at 4 mg/kg (maximum 200 mg) is recommended for Lyme disease prophylaxis after a high-risk tick bite, as recommended by the Infectious Diseases Society of America 1
Prophylactic treatment with doxycycline should only be offered when the tick can be reliably identified as an adult or nymphal Ixodes scapularis tick, the tick is estimated to have been attached for ≥36 hours, prophylaxis can be started within 72 hours after tick removal, the local rate of infection of ticks with Borrelia burgdorferi is ≥20%, and doxycycline is not contraindicated for the patient, as per the Infectious Diseases Society of America guidelines 1

Administer doxycycline with adequate fluid (8 ounces) to reduce esophageal irritation, and can be given with food to reduce gastrointestinal intolerance, as suggested by clinical guidelines 2
Advise patients to avoid sun exposure due to photosensitivity risk, as recommended by clinical guidelines 2
For children who develop early Lyme disease (erythema migrans), treatment options include amoxicillin (50 mg/kg/day in 3 divided doses, maximum 500 mg per dose) for 14 days, as recommended by the Infectious Diseases Society of America 3
Cefuroxime axetil (30 mg/kg/day in 2 divided doses, maximum 500 mg per dose) for 14 days is also a treatment option for children with early Lyme disease, as per clinical guidelines 3

Using first-generation cephalosporins (e.g., cephalexin) is ineffective against B. burgdorferi, as stated by clinical guidelines 2, 4
Prescribing prophylaxis when the tick has been attached for less than 36 hours, or delaying prophylaxis beyond 72 hours after tick removal, reduces effectiveness, as recommended by the Infectious Diseases Society of America 1
Using macrolide antibiotics for prophylaxis has lower efficacy, as suggested by clinical guidelines 2, 4