title: Clinical characteristics of imipramine-induced orthostatic hypotension.
abstract: The effects of imipramine hydrochloride on blood-pressure were examined in a prospective and a retrospective study. In a prospective study of 44 depressed patients given imipramine in doses to achieve antidepressant plasma-concentrations there was no effect of the drug on lying blood-pressure. When patients then stood up, the drug produced an average fall in systolic pressure of 26 mm Hg (t = 13.6, P less than 0.001) that was consistent over the four weeks of observation. Contrary to expectation, this fall was independent of patients' age, pre-existing heart-disease, or plasma-level of the drug. The best predictor of orthostatic hypotension during treatment was the degree of orthostatic drop in pressure before treatment (r = 0.695, P less than 0.001). In order to establish the clinical significance of this orthostatic drop in pressure, a retrospective study of 148 depressed patients treated with imipramine was conducted. These 148 patients, average age 59 years, received an average dose of 225 mg of imipramine. Almost 20% of them had symptoms usually associated with orthostatic hypotension that were severe enough to interfere with their treatment: over 4% sustained physical injuries. In our experience orthostatic hypotension is the commonest serious cardiovascular side-effect of imipramine.
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D003863:Depression / Q000188:drug therapy; D005260:Female; D006801:Humans; D007024:Hypotension, Orthostatic / Q000139:chemically induced*; D007099:Imipramine / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011187:Posture; D011446:Prospective Studies; D012189:Retrospective Studies; D013599:Systole / Q000187:drug effects
chemical_list: D007099:Imipramine