Effects of felodipine on the arterial blood pressure and fluidity of blood in patients with arterial hypertension WHO stage I

The aim of this investigation was to examine the effect of felodipine on the blood pressure and on the rheological properties of patients who suffer from arterial hypertension without secondary organic changes (WHO stage I) and had not undergone antihypertensive treatment up to that time. 104 patients were included in this randomised, placebo-controlled double-blind study. Felodipine significantly decreased the confirmatory parameters, the systolic and diastolic blood pressures, by 10% from 154 to 140 mmHg and from 94 to 85 mmHg respectively (p<0.001). A significant difference between felodipine and placebo was found for the exploratory parameters except for the haematocrit. Felodipine decreased the plasma viscosity by 7% (p<0.001), the erythrocyte aggregation by 12% (p<0.01), the spontaneous thrombocyte aggregation by 40% (p<0.001) and leukocyte adhesiveness by 24% (p<0.01). These parameters remained unchanged by placebo. One of the patients in the felodipine group complained of kidney pain and headache and discontinued the treatment. Another patient in the Felodipine group and two of the patients in the placebo group dropped out because of lack of compliance. Five patients in the felodipine group and 4 patients in the placebo group complained of adverse drug reactions such as headache, ankle edema, tiredness, kidney pain, gastrointestinal complaints and one had an attack of gout.