Biotin Side Effects
In general, biotin does not usually cause side effects, especially when it is taken at normal dosages. Only a few side effects of biotin have been reported, and it is difficult to tell whether biotin or other factors caused these side effects. In high dosages, biotin has been shown to cause miscarriages and decreased fetal growth when given to pregnant rats, but it is not known if these problems could occur in humans.
Does Biotin Cause Side Effects?Biotin typically does not cause side effects for most people, especially when taken at normal dosages. However, there may be rare, currently unknown biotin side effects that have not yet been reported.
(This article covers many, but not all, of the possible side effects with biotin. Your healthcare provider can discuss a more complete list of biotin side effects with you.)
Possible Side Effects of BiotinVery few side effects with biotin have been reported, even when extremely high doses were used (given either by mouth or by IV). In one case, a woman who took a high dose of biotin (along with vitamin B5) experienced a life-threatening lung and chest condition known as eosinophilic pleuropericardial effusion. However, this condition improved once she stopped taking biotin and vitamin B5. It is not known if the biotin, the vitamin B5, the combination of the two, or something else caused this problem.
When high doses of biotin were given to pregnant rats, it decreased the growth of the placenta and the fetal rats, and increased the risk of miscarriages. It is not known how or why these problems occurred or if similar problems could occur in humans.
If you think you are experiencing a biotin side effect, please let your healthcare provider know. Also, let your healthcare provider know if you develop something that "just does not seem right." While it may not be a side effect, your healthcare provider will be able to diagnose and treat the problem.