A randomized collective comparative study between nicardipine (N) and propranolol (P) was conducted over a period of 7 weeks in thirty hypertensive patients of both sexes, aged from 20 to 65 years, with the diastolic pressure over 100, but below 120 mmHg. Thirteen examinees were given N (60-120 mg daily) and seventeen P (120-240 mg daily); the groups were comparable according to a series of relevant parameters. In the placebo-period the mean arterial pressure (MAP) was slightly lowered, by 4.4% (p greater than 0.20). MAP was, however, considerably lowered already at the end of the second week of active treatment both in the N group (from 135.1 +/- 7.4 to 116 +/- 10.8 mmHg, or by 19.1%; P less than 0.01), as well as in the P group (from 131.6 +/- 8.1 to 117 +/- 9.1 mmHg, by an average of 11.1%; P less than 0.05). The values continued to decrease, and at the end of the seventh week of the study MAP averaged 108.5 +/- 6.5 mmHg (-19.7%; P less than 0.01) in the N group, while it was 109.7 +/- 9.1 mmHg (-16.6%; P less than 0.01) in the P group. The heart rate became considerably slower in the P group only, from the initial 84.5 +/- 9.2 to 66.9 +/- 2.7 beats per minute at the end of the seventh week (-20.8%; P less than 0.01), but it was unexpectedly, although not significantly lowered also in the N group, from the initial 78.3 +/- 6.5 to 74.2 +/- 4.0 beats (-5.2%; P greater than 0.20).(ABSTRACT TRUNCATED AT 250 WORDS)