Interaction between clonidine and desipramine in man.

Interaction between the tricyclic antidepressant desipramine and the antihypertensive agent clonidine has been investigated in five hypertensive patients in a double-blind placebo controlled study. Introduction of the tricyclic antidepressant led to loss of blood pressure control in four of the patients. The average blood pressure rise in the desipramine period compared with the placebo period was 22/15 mm Hg in the lying position and 12/11 mm Hg standing. Thus addition of a tricyclic antidepressant may lead to loss of blood pressure control in a hypertensive patient treated with clonidine.