KETANSERIN AND HYDROCHLOROTHIAZIDE IN THE TREATMENT OF ARTERIAL-HYPERTENSION

The chronic antihypertensive effect of the combination of ketanserin (KET) 40 mg + hydrochlorothiazide (HCTZ) 12.5 mg was evaluated in 20 patients with arterial hypertension of mild to moderate degree. After a 2-week wash-out period, patients were prescribed a single oral dose of KET 40 mg or HCTZ 25 mg in a randomized order at 2-day intervals and blood pressure and heart rate were measured during the following 24 hrs by an automatic recorder. Thereafter patients were given the combination of KET 40 mg + HCTZ 12.5 mg for 6 weeks and 24 hrs blood pressure was recorded after the first dose of the combination and at the end of treatment. Ketanserin induced a significant fall in systolic and diastolic pressures for up to 8 hrs; thiazide did not induce any change in these parameters. The combination of KET + HCTZ in the acute study reduced significantly systolic (SBP) and diastolic (DBP) blood pressures for up to 10 hrs. After 6 weeks of treatment with KET + HCTZ, blood pressure showed a further fall at each time period and was normalized (BP > 160/80 mmHg) for 8 hrs after dosing. The results of this study indicate that once daily oral administration of the combination of KET 40 mg + HCTZ 12.5 mg in mild to moderate primary hypertensives significantly reduces blood pressure over 24 hrs. Fairly good control of BP, i.e. BP < 160/90 mmHg, was, however, achieved only up to 8 hrs after drug administration, indicating that this combination given once daily is not able to normalize BP over the following 24 hrs.