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Herxheimer Reaction (HERX)

The Jarisch-Herxheimer reaction was originally noted in 1895 by Dr. Jarisch who worked with Syphyllis (a spirochete) patients.  In the 21st century, we observe Herxheimer reactions in tick-borne illnesses such as Lyme Disease, also caused by a spirochete.  A Herxheimer reaction (Herx) typically occurs hours to days after antimicrobial administration and is thought to be the result of endotoxins released into the bloodstream by dying spirochetes.  The body’s immune system then responds to the endotoxins and the concurrent release of cytokines (i.e., tumor necrosis factor, interleukin 6, and interleukin 8) which are chemical messenger molecules of the immune system producing exaggerated symptoms lasting 3 days up to several weeks.

Dr. Marra doses antibiotics specifically for the individual patient so that the Herxheimer reaction on a scale of 1-10, is about a 5.  This is her own technique, and she feels that severe Herxheimer reactions over prolonged periods of time may cause tissue damage from the excessive release of endotoxins and cytokines.  Tissues become friable as the result of chronic inflammation, not unlike what happens when a sponge is repeatedly used and the surface area becomes frayed.  Dr. Marra is not convinced that this kind of tissue damage is reversible which is why she chooses to take the route of treatment that she does.  However, many other physicians choose to treat more aggressively and seem to have good results. This is simply her own treatment preference.

The general description of a Herxheimer reaction is a temporary increase in symptoms but may also include the development of completely new symptoms.  More specifically, the most common complaints of a Herx reaction are increased joint and muscle pain, headaches, chills, night sweats, fever (usually low grade), extreme fatigue, and brain fog or lack of mental clarity, drop in blood pressure, hives, or a rash of some sort.  Worth noting here is that a rash or hives can sometimes be mistaken for an allergic reaction.  It is up to the treating physician to determine this, but with close, experienced observation and the use of Benadryl, Alka Seltzer Gold, Quercitin, warm lemon water and vitamin C (see Herx management), unnecessary premature cessation of antibiotics may be prevented.  In more severe cases of Herxheimer reactions, a reduction in the antibiotic dosage or cessation of the antimicrobials may be required.

The timing of a Herx reaction is very individualistic and can occur within days to weeks after the onset of antibiotic treatment.  In some patients, a Herxheimer reaction occurs only once or twice, or not at all throughout treatment.  It is clear however, that as you move through the treatment and the spirochetal load becomes decreased, the Herx reactions become less and less severe.  Herxheimer reactions can also occur in cycles (usually 4 week cycles) and may be affected by the lunar cycle.  This is anecdotal but it is an interesting observation in some people.

About 70-80% of people undergoing Lyme Disease treatment with antibiotics experience some sort of Herxheimer reaction.  It is thought by a number of physicians and scientists that these people have difficulty in detoxification processes, and that perhaps there may be a defect in one of the detox pathways in the liver.  This may be genetic, environmental or a combination of both.  But without question, maintaining an alkaline diet and an  “alkaline bioterrain” helps lessen the effects of a Herx reaction.  The 20% of patients who do not experience a Herx reaction should not feel like they are getting nowhere by taking antibiotics.  Discussion of this issue should be left to the patient and their treating physician.