According to WebMD, 5-Hydroxytryptophan (5-HTP) carries one serious side effect, which is the possible development of eosinophilia-myalgia syndrome (EMS), and numerous other less-serious side effects, such as heartburn, stomach discomfort, nausea, vomiting, diarrhea, fatigue, sexual issues and muscle issues. 5-HTP can also cause additionalissues in people who have other health conditions, such as those suffering from Down syndrome, women who are pregnant or breastfeeding or those who are undergoing recent surgery and taking other medications that can interfere with the 5-HTP.
5-HTP is produced as a protein building block L-tryptophan. It can be used to treat depression and fibromyalgia, and there is little evidence that it can be used to treat other health issues, such as Alzheimer's, anxiety, nervous system disorders, headache, menopausal symptoms and more.
According to WebMD,EMS is a more serious side effect that is often associated with the use of5-HTP. Some experts connect the use of 5-HTP with EMS due to some ingredients that are found in 5-HTP, such as contaminants. These contaminants are found in certain 5-HTP products and not in others. While this connection with EMS has not been fully proven, it is recommended to take the necessary precautions when taking5-HTP. Those with Down syndrome should take precautions with 5-HTP, because it has been linked to possible seizures.