Reaction to endotoxin-like products released by the lysis (destruction) of bacterial cell membranes within the body during antibiotic treatment.
History
Adolf Jarisch, an Austrian dermatologist, and Karl Herxheimer, a German dermatologist, are credited with the discovery of the Jarisch–Herxheimer reaction. Both Jarisch and Herxheimer observed reactions in patients with syphilis treated with mercury. The reaction was first seen following treatment in early and later stages of syphilis treated with Salvarsan, mercury, or antibiotics. Jarisch thought that the reaction was caused by a toxin released from the dying spirochetes.
Aetiology
Antibiotic treatment of:
- Syphilis (M/C, 45% develop JHR)
- Spirochete diseases:
- Lyme disease (7–30% develop JHR)
- Relapsing fever (35-45% develop JHR)
- Leptospirosis (9% develop JHR)
- Other infections: Q fever, bartonellosis, brucellosis, trichinellosis, and African trypanosomiasis
Pathophysiology

Clinical features
- Flu-like syndrome: Fever, chills, headache, myalgia
- Exacerbation of skin rashes



Management
Prophylaxis and treatment with an anti-inflammatory agent:
- Oral aspirin/ibuprofen (4 hourly for 1 day) or oral/IV prednisone 60 mg