Pressor response of oral tyramine in healthy men given amiflamine and placebo.

Abstract

During two baseline challenge tests, oral tyramine (50 to 400 mg) was given to 12 healthy men to find each individual's cardiovascular pressor response. All 12 subjects "tolerated" 200 mg oral tyramine, but three of the 12 developed an increment in systolic blood pressure greater than 30 mm Hg when given a dose of 400 mg. Thereafter, amiflamine, 5 mg bid (n = 8), or placebo, 1 capsule twice a day (n = 4), were given in a double-blind fashion for 7 days, and oral tyramine challenge tests (12.5 to 400 mg) were given on days 5 to 7. During dosing with amiflamine or placebo, no subject tolerated 400 mg oral tyramine and no difference between the two regimens was found with regard to tyramine response. Plasma concentrations of amiflamine and two of its metabolites were measured on days 4 to 7. Steady-state concentrations were reached within 4 to 5 days. Plasma concentrations of tyramine after 400 mg tyramine showed a positive correlation with the increase in systolic blood pressure (P less than 0.001).