[3] On February 28, 2017, the U.S. Food and Drug Administration (FDA) approved telotristat ethyl in combination with somatostatin analog (SSA) therapy for the treatment of adults with diarrhea associated with carcinoid syndrome that SSA therapy alone has inadequately controlled.

[5][6] Telotristat ethyl was approved for use in the European Union in September 2017.

[4] The U.S. Food and Drug Administration (FDA) considers it to be a first-in-class medication.

[7] Telotristat is an inhibitor of tryptophan hydroxylase,[8] which mediates the rate-limiting step in serotonin biosynthesis.

[3] Common adverse effects noted in clinical trials include nausea, headache, elevated liver enzymes, depression, accumulation of fluid causing swelling (peripheral edema), flatulence, decreased appetite, and fever.