[Hypotensive effects of mononitrates (IS-5-MN) in light of 24-hour blood pressure monitoring].

Our study was aimed to evaluate the hypotensive effects of a single dose of 100 mg IS-5-MN (Mack) using ambulatory blood pressure monitoring (ABPM). We have enrolled into the study 50 patients. Twenty-one of them were hypertensive (WHO-class I and II) and twenty nine were normotensive. The mean age of the patients was 52.88 +/- 12 years. ABPM was performed during 48 hours. After first 24 hours without any hypotensive drugs the IS-5-MN or placebo was given in double blind study. The readings in the second 24 hours were taken in the same procedure as in the first 24 hours i.e. every twenty minutes between 7.00 and 23.00 every half an hour between 23.00 and 7.00. Mean hourly systolic (SBP) and diastolic (DBP) blood pressures of the first day (without any treatment) and 2nd day (IS-5-MN or placebo) were compared in four group of patients:1. Hypertensives receiving placebo, 2. Hypertensives receiving IS-5-MN, 3. Normotensives receiving placebo and 4. Normotensives receiving IS-5-MN. Only in the fourth group of patients mean hourly blood pressures from the day 2 were significantly lower than from the day I. First hypotensive effects for SBP as well as for DBP were observed four hour after IS-5-MN was given. These effects last about 8 hours. These data confirm the hypotensive effects of mononitrates in normotensive patients.