In 23 hypertensive men, aged 47-55, propranolol reduced serum high-density-lipoprotein (HDL) cholesterol by 13% reduced the ratio of HDL to low-density-lipoprotein (LDL)+very-low-density-lipoprotein (VLDL) cholesterol by 15%, increased total triglycerides by 24%, and increased serum uric acid by 10%. Prazosin reduced total serum cholesterol by 9%, LDL+VLDL cholesterol by 10%, and total triglycerides by 16%. These changes are statistically highly significant. On combined treatment with propranolol and prazosin HDL cholesterol was still significantly reduced but changes in other blood lipids were small and insignificant. Uric acid remained elevated. When decisions about long-term therapy are made, such metabolic effects might be of special importance.