Treatment for Lyme Disease
For early Lyme disease with erythema migrans, treat adults with doxycycline 100 mg twice daily for 14 days (10 days is sufficient), amoxicillin 500 mg three times daily for 14 days, or cefuroxime axetil 500 mg twice daily for 14 days 1.
First-Line Oral Therapy for Early Lyme Disease
The IDSA guidelines provide clear, evidence-based recommendations for treating early localized or early disseminated Lyme disease:
Adults
- Doxycycline: 100 mg twice daily for 10-21 days (10 days is sufficient)
- Amoxicillin: 500 mg three times daily for 14-21 days
- Cefuroxime axetil: 500 mg twice daily for 14-21 days
Doxycycline has a distinct advantage: it also treats human granulocytic anaplasmosis (HGA), which can occur as a coinfection in the same geographic areas 1.
Children
- Amoxicillin: 50 mg/kg/day in 3 divided doses (maximum 500 mg per dose)
- Cefuroxime axetil: 30 mg/kg/day in 2 divided doses (maximum 500 mg per dose)
- Doxycycline (if ≥8 years old): 4 mg/kg/day in 2 divided doses (maximum 100 mg per dose)
Doxycycline is not recommended for children under 8 years, pregnant women, or breastfeeding women 1.
Alternative Therapy (Second-Line)
Macrolides are significantly less effective and should only be used when patients cannot tolerate doxycycline, amoxicillin, or cefuroxime axetil 1:
- Azithromycin: 500 mg daily for 7-10 days (adults); 10 mg/kg/day for children
- Clarithromycin: 500 mg twice daily for 14-21 days (not in pregnancy)
- Erythromycin: 500 mg four times daily for 14-21 days
Patients on macrolides require close monitoring to ensure clinical resolution 1.
Neurologic Lyme Disease
For meningitis or radiculopathy, parenteral therapy is required 1:
Adults
- Ceftriaxone: 2 g IV once daily for 14 days (range 10-28 days)
- Alternatives: Cefotaxime 2 g IV every 8 hours or Penicillin G 18-24 million units/day IV divided every 4 hours
Children
- Ceftriaxone: 50-75 mg/kg IV once daily (maximum 2 g) for 14 days (range 10-28 days)
For isolated cranial nerve palsy (e.g., facial palsy), oral therapy is sufficient using the same regimens as early Lyme disease 1.
Lyme Carditis
The 2020 IDSA/AAN/ACR guidelines recommend 2:
- Outpatients: Oral antibiotics (doxycycline, amoxicillin, cefuroxime axetil, or azithromycin)
- Hospitalized patients: Start with IV ceftriaxone until clinical improvement, then switch to oral therapy
- Duration: 14-21 days total
Hospitalize patients with PR interval >300 milliseconds, other arrhythmias, or myopericarditis manifestations 2.
Lyme Arthritis
Oral antibiotics for 28 days are recommended as initial therapy 2:
- Use the same oral regimens as for early Lyme disease
- If partial response after first course, consider second course or observation
Critical Pitfalls to Avoid
Do NOT use the following for any manifestation of Lyme disease 1:
- First-generation cephalosporins (e.g., cephalexin) - completely ineffective
- Fluoroquinolones
- Benzathine penicillin G
- Long-term antibiotic therapy beyond recommended durations
- Combination antimicrobial therapy
- Pulsed-dosing regimens
Ceftriaxone is NOT superior to oral agents for early Lyme disease without neurologic involvement and causes more adverse effects - do not use it for uncomplicated erythema migrans 1.
Special Considerations
Pregnancy and Lactation
Treat identically to non-pregnant patients except avoid doxycycline - use amoxicillin or cefuroxime axetil instead 1.
Coinfection
Consider coinfection with Babesia or Anaplasma if patients have 1:
- High fever persisting >48 hours despite appropriate Lyme treatment
- Unexplained leukopenia, thrombocytopenia, or anemia
- More severe initial symptoms than typical for Lyme disease alone
Post-Treatment Symptoms
Do NOT give additional antibiotics to patients with persistent nonspecific symptoms (fatigue, pain, cognitive complaints) after completing appropriate treatment, unless there are objective signs of active disease like arthritis, meningitis, or neuropathy 2.
Duration Nuances
While 14 days is recommended for uniformity across all first-line oral agents, 10 days of doxycycline is sufficient for erythema migrans based on high-quality evidence 1. The longer duration recommendation for beta-lactams reflects their shorter half-life and lack of data supporting 10-day courses 1.
The most recent 2025 French guidelines 3 and 2020 IDSA/AAN/ACR guidelines 2, 4 align with these recommendations, confirming doxycycline as first-line therapy with treatment durations of 10-28 days depending on clinical presentation.