The Herxheimer Reaction is a short-term (from days to a few weeks) detoxification reaction in the body. As the body detoxifies, it is not uncommon to experience flu-like symptoms including headache, joint and muscle pain, body aches, sore throat, general malaise, sweating, chills, nausea or other symptoms.
This is a normal — and even healthy — reaction that indicates that parasites, fungus, viruses, bacteria or other pathogens are being effectively killed off. The biggest problem with the Herxheimer reaction is that people stop taking the supplement or medication that is causing the reaction, and thus discontinue the very treatment that is helping to make them better. Although the experience may not make you feel particularly good, the Herxheimer Reaction is actually a sign that healing is taking place.