Four to seven-year follow-up of patients on prazosin. New Zealand Hypertension Study Group.

The progress of 172 hypertensive patients who were taking prazosin at the end of a multicentre study in March 1976 was re-surveyed in 1979. Three patients could not be traced. Mean duration of prazosin treatment in the remainder was 57 months. One hundred and ten patients were still taking prazosin; blood pressure control was good and there was no evidence of the development of tolerance. Mean daily dose was 9 mg. Fifty-nine patients had stopped the drug; 16 of these had died, mainly of cardiac causes, 21 had stopped because of possible or probable side effects and 22 for other reasons. No long-term toxic effects have become apparent.