Influence of nomifensine and desipramine on tyramine pressor responses in healthy volunteers.

1. Pressor responses following a series of bolus intravenous injections of tyramine were used to assess the influence of single oral doses of nomifensine 75 mg on peripheral sympathetic neuronal uptake mechanisms in healthy volunteers. Desipramine 50 mg served as a positive control. 2. Following each treatment the effect of tyramine was diminished, with a shift to the right in the tyramine dose-response curve. In addition, there was a suggestion that in these experimental conditions nomifensine was less potent than desipramine.