Q: Can l-tryptophan and 5 HTP cause increased B/P? I take both for insomnia. They metabolize to serotonin.
A: Any drug or supplement can cause a serious adverse reaction. There are common side effects and rare side effects. It is possible the use of these supplements could cause high blood pressure. There is concern that l-tyrptophan and 5HTP use may cause the serious problem eosinophilia-myalgia syndrome. This side effect can persist even after the drug is stopped. To learn more go to this article at the National Center for Complementary and Alternative Medicine site.