What are the guidelines for treating Lyme disease?

Guidelines for Treating Lyme Disease

For patients with Lyme disease, oral doxycycline (100mg twice daily for 10 days) is the first-line treatment for early localized disease, while specific parenteral regimens are recommended for more severe manifestations involving the nervous system, joints, or heart. 1

Prevention and Prophylaxis

Tick Bite Prevention

• Use EPA-registered repellents: DEET, picaridin, IR3535, oil of lemon eucalyptus, PMD, 2-undecanone, or permethrin 1
• Remove attached ticks promptly using fine-tipped tweezers 1
• Do not burn ticks or apply chemicals to remove them 1

Post-Tick Bite Management

• Prophylactic antibiotics only recommended for high-risk tick bites meeting ALL criteria:
  • Identified Ixodes species tick
  • Tick attached ≥36 hours
  • Bite occurred in highly endemic area
  • Treatment within 72 hours of tick removal 1
• Recommended prophylaxis: Single dose of doxycycline (200mg for adults, 4.4mg/kg up to 200mg for children) 1
• Testing asymptomatic patients after tick bites is not recommended 1

Treatment of Lyme Disease by Stage

Early Localized Disease (Erythema Migrans)

• First-line treatments (choose one):
  • Doxycycline: 100mg twice daily for 10 days
  • Amoxicillin: 500mg three times daily for 14 days
  • Cefuroxime axetil: 500mg twice daily for 14 days 1
• Second-line treatment:
  • Azithromycin: 500mg on day 1, then 250mg daily for 4-9 days (7-day course preferred) 1
• Laboratory testing not required for typical erythema migrans in endemic areas 1

Early Disseminated Disease

• Multiple erythema migrans without neurologic involvement:

  • Same oral regimens as early localized disease 1, 2
  • Oral doxycycline is as effective as parenteral ceftriaxone for disseminated disease without meningitis 2

• Neurologic Lyme disease (meningitis, radiculopathy):

  • Preferred: Ceftriaxone 2g IV once daily for 14-21 days 1
  • Alternatives: Cefotaxime 2g IV every 8h or penicillin G 18-24 million units IV daily divided every 4h 1
  • For isolated facial nerve palsy without other neurologic signs: oral regimens may be used 1

• Lyme carditis:

  • For outpatients with mild carditis: oral antibiotics 1
  • For patients with severe cardiac complications (PR >300ms, arrhythmias, myopericarditis): hospitalization with continuous ECG monitoring 1
  • Temporary pacing for symptomatic bradycardia rather than permanent pacemaker 1

Late Disease (Lyme Arthritis)

• Initial treatment with oral antibiotics (same as for early disease) 1
• For persistent arthritis after oral therapy: IV ceftriaxone 2g daily for 14-28 days 1

Special Populations

Children

• For children ≥8 years: doxycycline is first-line (same as adults) 1
• For children <8 years: traditionally amoxicillin has been preferred due to concerns about dental staining with doxycycline 1
• Recent evidence suggests short courses of doxycycline (≤21 days) may be safe in younger children 3, 4
• Pediatric dosing:
  • Amoxicillin: 50mg/kg/day in 3 divided doses (max 500mg per dose)
  • Doxycycline: 4mg/kg/day in 2 divided doses (max 100mg per dose) 1

Pregnant Women

• Doxycycline is contraindicated
• Use amoxicillin, cefuroxime, or IV regimens as appropriate for disease stage 1

Treatment Pitfalls and Caveats

1. Avoid inappropriate treatments:

   • Do not use first-generation cephalosporins, fluoroquinolones, carbapenems, vancomycin, metronidazole, or combinations of antimicrobials 1
   • Avoid prolonged or repeated courses of antibiotics beyond recommended durations 1

2. Diagnostic considerations:

   • Do not routinely test for Lyme disease in patients with psychiatric illness or developmental disorders 1
   • In areas where both STARI and Lyme disease are endemic, treat erythema migrans with Lyme disease regimens if the tick species is unknown 1

3. Coinfection awareness:

   • Consider coinfection with Babesia or Anaplasma in patients with more severe initial symptoms, high-grade fever persisting >48h despite appropriate antibiotics, or unexplained cytopenias 1

4. Post-treatment symptoms:

   • Persistent symptoms after appropriate treatment may not represent ongoing infection
   • Distinguish between treatment failure and post-Lyme disease syndrome 1, 2
   • Avoid prolonged antibiotic therapy for persistent symptoms when there is no evidence of active infection 1

The evidence strongly supports short-course antibiotic therapy for most manifestations of Lyme disease, with specific regimens based on disease stage and organ involvement.