Jarisch-Herxheimer reaction

(Redirected from Jarisch-Herxheimer Reaction)


  • A systemic reaction caused by reaction to endotoxins released by the death of harmful organisms within the body
  • Occurs following antibiotic treatment for a number of spirochetal and bacterial infections (classically described in the treatment of syphilis)
  • Can also occur following treatment of tick-borne relapsing fever (TBRF) or Lyme disease
  • Both penicillin and tetracycline can induce JHR
  • Resembles bacterial sepsis.
  • Tends to occur within two hours of antibiotic administration
    • Lasts for a few hours or up to a day
  • Mortality rate from JHR in louse-borne relapsing fever (LBRF) in the absence of adequate monitoring and resuscitation measures is ~5%.

Clinical Features

Jarisch–Herxheimer reaction in a person with syphilis.

Occurs 2 to 6 hours after treatment started; symptoms can last for 24 hours

  • Malaise
  • Fever
  • Rigors
  • Flushing (due to vasodilation)
  • Hypotension
  • Tachycardia
    • Tachycardia and hyperventilation are accompanied by hypertension, and then by a drop in blood pressure due to vasodilation and declining peripheral pulse.

Differential Diagnosis


  • Typically a clinical diagnosis



  • Outpatient

See Also