title: Felodipine in combination with a beta-blocker and a diuretic in chronic treatment of patients with refractory primary hypertension.
abstract: The acute antihypertensive effects of the dihydropyridine calcium antagonist, felodipine, were investigated in 12 male patients aged 43 to 64 years with uncontrolled blood pressure on combined treatment with a thiazide diuretic, a beta-blocker and hydralazine. Central and renal haemodynamics were monitored after acute oral administration (0.075 mg/kg) of felodipine in combination with the beta-blocker and diuretic. Six patients were continued on long term oral felodipine (mean dose 20 +/- 24 mg/day) in combination with the other drugs for 6 to 18 months. Ambulatory blood pressure was measured repeatedly and renal function re-examined once during long term felodipine therapy. In the 6 patients on long term therapy, systolic blood pressure was reduced from 190 +/- 17 to 149 +/- 24 mm Hg and diastolic blood pressure from 116 +/- 12 to 89 +/- 14mm Hg (p less than 0.001). No significant change in heart rate was observed (65 +/- 4 vs 62 +/- 10 beats/min). Renal plasma flow significantly increased from 284 +/- 97 to 425 +/- 131 ml/min/m2 (p less than 0.01) but glomerular filtration rate was unchanged (72 +/- 20 vs 80 +/- 22 ml/min/m2). Hence, the filtration fraction was significantly reduced and normalised in all patients (0.26 +/- 0.04 vs 0.20 +/- 0.03) [p less than 0.05]. Bodyweight was unchanged. It is concluded that felodipine is a highly potent vasodilator with a favourable effect on renal function and is suitable for long term therapy in patients with severe primary hypertension.
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D004232:Diuretics / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D015736:Felodipine; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006830:Hydralazine / Q000627:therapeutic use; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009568:Nitrendipine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D012079:Renal Circulation / Q000187:drug effects
chemical_list: D000319:Adrenergic beta-Antagonists; D000959:Antihypertensive Agents; D004232:Diuretics; D006830:Hydralazine; D009568:Nitrendipine; D015736:Felodipine