Effect of prazosin on blood pressure and plasma lipids in patients receiving a beta-blocker and diuretic regimen.

When prazosin was added to a beta-blocker/diuretic regimen, there was a further and statistically significant (p less than 0.05) reduction in blood pressure (12.7 percent supine diastolic pressure) but no significant change in heart rate. Mean high-density lipoprotein cholesterol increased by 10.8 percent (p less than 0.05) during prazosin treatment whereas very low-density lipoprotein and low-density lipoprotein cholesterol decreased. Together these changes contributed to a significant (p less than 0.05) increase in the ratio of high-density lipoprotein: low-density lipoprotein plus very low-density lipoprotein cholesterol of 13.3 percent. The reduction in total cholesterol was more marked in patients with elevated cholesterol levels (260 mg/100 ml or greater); in this group, total cholesterol and triglyceride levels were significantly reduced (p less than 0.05) during prazosin treatment.