Lyme Disease Treatment: Antibiotics, Duration & Cure Rates by Stage

Lyme disease (Borrelia burgdorferi sensu lato) is highly treatable with antibiotics. **Early treatment = near 100% cure.** Delayed treatment reduces but does not eliminate cure probability.

Treatment Regimens (IDSA / CDC / NICE Guidelines)

Stage	Preferred Regimen	Duration	Alternatives
Early Localized (EM rash)	Doxycycline 100 mg PO BID	10 days (7–14)	Amoxicillin 500 mg TID, Cefuroxime 500 mg BID
Early Disseminated (multiple EM, CN VII palsy, carditis)	Doxycycline 100 mg BID	14–21 days	Ceftriaxone 2 g IV daily (if CNS/cardiac)
Late (Arthritis)	Doxycycline 100 mg BID	28 days	Ceftriaxone 2 g IV daily × 14–28d (if neuroborreliosis)

Special Populations

• Pregnancy: Amoxicillin 500 mg TID × 14–21d (doxy contraindicated).
• Children <8 yr: Amoxicillin (doxy if >8).
• Neuroborreliosis: Ceftriaxone 2 g IV q24h × 14–28d (penetrates CSF).
• Carditis: Hospitalize, monitor, ceftriaxone IV.

Cure Rates

• Early localized: 95–100% with appropriate treatment.
• Early disseminated: 90–95%.
• Late arthritis: 80–90% (some residual inflammation post-clearance — “antibiotic-refractory” = immune-mediated, not persistent infection).
• Neuroborreliosis: >90% with IV ceftriaxone.

Post-Treatment Lyme Disease Syndrome (PTLDS)

• Persistent fatigue, pain, cognitive symptoms >6 mo post-treatment.
• No evidence of persistent infection (xenodiagnosis, PCR, culture negative).
• Management: Symptomatic (pain, sleep, cognitive rehab, graded exercise); no benefit from prolonged antibiotics (multiple RCTs).

Prevention

• Permethrin-treated clothing, DEET/Picaridin repellent.
• Tick checks within 24h (attachment <36h rarely transmits).
• Single-dose doxy 200 mg within 72h of high-risk bite (endemic areas, engorged nymph).

Complete the prescribed course. Retreatment only if objective evidence of failure (persistent EM, recurrent arthritis with PCR+ synovial fluid).