Sitagliptin is devoid of the capacity for Cyp-interaction, and thus for pharmacokinetic porphyrogenicity. Side effects such as nausea and vomiting may be potentially porphyrinogenic through reduction in carbohydrate intake. Infections are also a common reported side effect, and infections are well known triggers of acute porphyric attacks.

Trifluorophenyl-triazolpyrazine salt.

Sitagliptin is indicated to improve glycaemic control in adult patients with type 2 diabetes mellitus, and can be used in mono therapy or as part of combination therapy with other anti-diabetic drugs. Sitagliptin is a dipeptidyl peptidase 4 (DPP-4) inhibitor. It is administered orally. The pharmacodynamic effects on glucose homeostasis, with inhibition of pancreatic glucagon release, are theoretically anti-porphyrogenic Side effects such as nausea and vomiting may be potentially porphyrinogenic through reduction in carbohydrate intake. Upper respiratory tract infection and nasopharyngitis are also common reported side effects of sitagliptin, and such infections might trigger of acute porphyric attacks.

Approximately 79 per cent of sitagliptin is excreted unchanged in the urine. Nonclinical studies indicate that the small portion of sitagliptin that undergoes biotransformation is metabolized by Cyp3A4 with the help of Cyp2C8. In vitro data has shown that sitagliptin is not an inhibitor of CYP isozymes CYP3A4, 2C8, 2C9, 2D6, 1A2, 2C19 or 2B6, and is not an inducer of CYP3A4 and CYP1A2