COMT inhibition with nitecapone does not affect the tyramine pressor response.

Nitecapone (OR-462) is a new selective COMT inhibitor with gastroprotective properties. The aim of the present study was to determine whether nitecapone potentiates the haemodynamic effects of a tyramine-induced increase in catecholamine release. The systolic blood pressure response to tyramine was studied in 11 healthy male volunteers (age 20-32 years). Tyramine was given i.v. as rapid bolus injections in increasing doses without drug intake and after oral intake of single doses of 25 mg and 100 mg of nitecapone. The tyramine dose required to increase systolic blood pressure by 30 mm Hg ('pressor dose') was 4.98 mg, 5.04 mg and 4.88 mg after no medication, and with 25 mg and 100 mg of nitecapone, respectively. There were also no differences in the systolic blood pressure response vs time curves between the three regimens. COMT inhibition with nitecapone did not potentiate the haemodynamic responses to tyramine-induced catecholamine release.