How should an antibiotic be taken after a tick bite? - briefly
Take doxycycline 100 mg orally once daily for 10–14 days, beginning as soon as possible after the bite, unless contraindicated. If doxycycline cannot be used, prescribe amoxicillin 500 mg three times daily for the same period.
How should an antibiotic be taken after a tick bite? - in detail
Antibiotic therapy after a tick bite is indicated when the risk of transmitting a bacterial pathogen, such as Borrelia burgdorferi, is high. High‑risk situations include attachment for more than 36 hours, exposure in an area where Lyme disease is endemic, and identification of an adult Ixodes species. In these cases, a single dose of prophylactic medication reduces the likelihood of infection.
The preferred drug for most adults is doxycycline, administered as a 200 mg oral dose taken once, preferably within 72 hours of the bite. If doxycycline is contraindicated—due to allergy, pregnancy, or age under eight years—alternatives are amoxicillin 500 mg taken twice daily for ten days, or cefuroxime axetil 500 mg twice daily for ten days.
Dosage and administration guidelines
- Doxycycline: 200 mg PO, single dose; take with a full glass of water; remain upright for at least 30 minutes; may be taken with food to lessen stomach irritation.
- Amoxicillin: 500 mg PO, twice daily for ten days; ingest with water; food does not affect absorption.
- Cefuroxime axetil: 500 mg PO, twice daily for ten days; swallow whole tablets; food may improve tolerability.
Patients should monitor for early signs of infection: erythema migrans rash, fever, chills, headache, myalgia, or arthralgia. Appearance of any of these symptoms warrants immediate medical evaluation and, if confirmed, a full therapeutic course of doxycycline (100 mg twice daily for 14–21 days) or the appropriate alternative regimen.
Adherence to the prescribed schedule, correct dosing, and prompt reporting of adverse reactions—such as gastrointestinal upset, photosensitivity, or allergic response—are essential for optimal prevention of tick‑borne disease.