What is prescribed for a tick bite? - briefly
A single dose of doxycycline (100 mg) administered within 72 hours of tick removal is the recommended therapy for most patients, including children over eight years of age. If doxycycline is contraindicated, amoxicillin or cefuroxime are prescribed as alternatives.
What is prescribed for a tick bite? - in detail
A tick bite requires prompt removal of the attached arthropod, followed by assessment of the risk of pathogen transmission. The clinician determines whether antimicrobial prophylaxis is indicated based on the tick species, duration of attachment, geographic prevalence of tick‑borne diseases, and the patient’s health status.
Antibiotic prophylaxis for Lyme disease
- Doxycycline 200 mg orally as a single dose, administered within 72 hours of removal, is recommended when the following criteria are met:
- Ixodes scapularis or Ixodes pacificus identified;
- Tick attached for ≥ 36 hours;
- Local infection rate of nymphal ticks ≥ 20 %;
- No contraindication to doxycycline (e.g., pregnancy, children < 8 years, severe hepatic impairment).
- If doxycycline is unsuitable, amoxicillin 2 g orally as a single dose may be used, though evidence for efficacy is weaker.
Treatment of established infection
- Early localized Lyme disease (erythema migrans) is managed with:
- Doxycycline 100 mg twice daily for 10–21 days;
- Amoxicillin 500 mg three times daily for 14–21 days (alternative for doxycycline‑intolerant patients);
- Cefuroxime axetil 500 mg twice daily for 14–21 days (alternative).
- Neurologic or cardiac involvement necessitates intravenous ceftriaxone 2 g daily for 14–28 days.
Rocky Mountain spotted fever (RMSF)
- Doxycycline 100 mg orally or intravenously twice daily for 7–10 days, initiated promptly regardless of patient age. Delay increases mortality.
Other tick‑borne infections
- Anaplasmosis: Doxycycline 100 mg twice daily for 10 days.
- Ehrlichiosis: Doxycycline 100 mg twice daily for 7–14 days.
- Babesiosis: Combination therapy with atovaquone 750 mg daily plus azithromycin 500 mg daily for 7–10 days.
Supportive measures
- Analgesics (acetaminophen or ibuprofen) for pain and fever.
- Tetanus booster if immunization status is uncertain and the wound is contaminated.
- Observation for systemic signs (fever, headache, rash, arthralgia) for at least 30 days post‑bite; seek medical care if they develop.
Follow‑up
- Re‑evaluation at 2–4 weeks to confirm resolution of symptoms or to adjust therapy based on serologic testing.
- Persistent or recurrent manifestations may require extended antibiotic courses or specialist referral.
In summary, prescription decisions after a tick bite hinge on prophylactic criteria for Lyme disease, immediate treatment of confirmed infections, and appropriate supportive care, all tailored to the patient’s age, comorbidities, and regional disease patterns.