What is the recommended treatment for Lyme disease?

Treatment of Lyme Disease

For early Lyme disease in adults, doxycycline 100 mg twice daily for 10-14 days is the preferred first-line treatment, with amoxicillin 500 mg three times daily for 14 days as an alternative for pregnant women and children under 8 years. 1, 2

First-Line Oral Regimens for Early Lyme Disease

Adults

• Doxycycline 100 mg orally twice daily for 10-14 days (range 10-21 days) is the preferred agent because it also treats human granulocytic anaplasmosis (HGA), which can occur simultaneously with Lyme disease 1, 2
• Amoxicillin 500 mg orally three times daily for 14-21 days is the alternative for pregnant/lactating women and when doxycycline is contraindicated 3, 2
• Cefuroxime axetil 500 mg orally twice daily for 14-21 days is another effective option 2

Children

• Children ≥8 years: Doxycycline 4 mg/kg per day in 2 divided doses (maximum 100 mg per dose) for 10-14 days 1, 2
• Children <8 years: Amoxicillin 50 mg/kg per day in 3 divided doses (maximum 500 mg per dose) for 14 days 1, 2
• Alternative for children <8 years: Cefuroxime axetil 30 mg/kg per day in 2 divided doses for 14 days 1

Important note: Recent evidence suggests doxycycline may be safe and effective in children under 8 years for courses ≤3 weeks, though amoxicillin remains preferred 4, 5. The 2018 American Academy of Pediatrics stated that up to 3 weeks of doxycycline is safe in children of all ages 5.

Duration Considerations

• Doxycycline requires only 10 days due to its longer half-life 1, 2
• β-lactam antibiotics (amoxicillin, cefuroxime) require a full 14-day course due to their shorter half-life 1
• Extending treatment beyond 21 days is not supported by evidence and does not improve outcomes 2

Neurologic Lyme Disease

Isolated Facial Nerve Palsy (Seventh Cranial Nerve)

• Oral antibiotics (same regimens as early Lyme disease) for 14-21 days if no clinical signs of meningitis and normal CSF or CSF examination deemed unnecessary 3
• Lumbar puncture is indicated only if there is strong clinical suspicion of CNS involvement (severe/prolonged headache, nuchal rigidity) 3

Lyme Meningitis or CNS Involvement

• Ceftriaxone 2 g IV once daily (or 50-75 mg/kg per day for children, maximum 2 g) for 14-28 days 3, 1, 6
• Alternative: Cefotaxime 2 g IV every 8 hours (or 150-200 mg/kg per day divided into 3-4 doses for children, maximum 6 g per day) 3, 6
• Alternative: Penicillin G 18-24 million units per day IV divided every 4 hours (or 200,000-400,000 units/kg per day for children) 3, 6
• For penicillin-allergic patients: Doxycycline 200-400 mg/day orally or IV in 2 divided doses may be adequate 3

Lyme Carditis

• Hospitalized patients with symptomatic carditis or second/third-degree heart block: Start with IV ceftriaxone (same dosing as meningitis), then switch to oral regimen to complete 14-21 days total 3
• Outpatients with mild carditis: Oral regimens (same as early Lyme disease) for 14-21 days 3
• Hospitalization and continuous monitoring are required for symptomatic patients (syncope, dyspnea, chest pain) or those with second/third-degree AV block, or first-degree block with PR interval ≥30 milliseconds 3

Lyme Arthritis

• Initial treatment: Oral antibiotics (same regimens as early Lyme disease) for 28 days 3
• If arthritis improves but not resolved: Consider a second 4-week course of oral antibiotics 3
• If no response to oral therapy: IV ceftriaxone 2 g once daily for 14-28 days 3, 6
• Antibiotic-refractory arthritis (persistent synovitis ≥2 months after IV ceftriaxone AND negative PCR for B. burgdorferi): Symptomatic treatment with NSAIDs, intra-articular corticosteroids, or DMARDs; consider arthroscopic synovectomy 3

Critical Administration Instructions

Doxycycline

• Take with 8 ounces of fluid to reduce esophageal irritation 1, 7
• Take with food to minimize gastrointestinal intolerance 1, 7
• Avoid sun exposure due to photosensitivity risk 1, 7
• Absorption is not significantly affected by food or milk, unlike other tetracyclines 7

Pregnancy and Lactation

• Use amoxicillin or cefuroxime axetil; avoid doxycycline 3, 2
• Treatment regimens are otherwise identical to non-pregnant patients 3

Common Pitfalls to Avoid

Ineffective Antibiotics (Never Use)

• First-generation cephalosporins (e.g., cephalexin) are completely inactive against B. burgdorferi 1, 2, 6
• Fluoroquinolones, carbapenems, vancomycin, metronidazole, tinidazole are ineffective 3, 6
• Macrolides (azithromycin, clarithromycin, erythromycin) are significantly less effective and should only be used when patients cannot tolerate all first-line agents 1, 2, 6

Inappropriate Treatment Approaches

• Long-term antibiotic therapy beyond recommended durations lacks supporting data and may cause harm 1, 6
• Multiple repeated courses, combination therapy, or pulsed-dosing are not recommended 3, 6
• Doses far in excess of standard regimens are not indicated 3

Post-Treatment Considerations

• Serologic tests remain positive for months to years after successful treatment and should not be used to assess cure 6
• Most patients respond promptly and completely to appropriate therapy 1
• Less than 10% have persistent objective manifestations despite appropriate treatment 1
• Persistent nonspecific symptoms without objective findings do not warrant additional antibiotics 6
• Consider co-infections (Babesia, Anaplasma) if fever or characteristic laboratory abnormalities persist 6

budget:token_budget Tokens used this turn: 4523 Tokens remaining: 195477