Efficacy of captopril and nifedipine in black and white patients with hypertensive crisis.
We examined the antihypertensive efficacy of: (1) sublingual-oral single doses of captopril (25 mg) and nifedipine-capsules (10 mg) in 9 + 9 white patients and in 9 + 8 black patients with hypertensive crisis; and (2) a single oral dose of the slow-acting preparation of nifedipine-retard (20 mg) in another 10 black patients. Blood pressure (BP) was assessed at 10 min intervals for 6 h after administration. After 6 h, the BP falls induced by these drugs were still significantly lower than the baseline placebo values. Hypotensive effect of nifedipine-capsules was established more rapidly than that of captopril in both white and black patients, and of nifedipine-retard in black patients. Considering the area under the curve of BP values during the 6-h treatment, the overall hypotensive effect of nifedipine-capsules was similar to captopril in white patients, but significantly more pronounced than captopril and nifedipine-retard in black patients. In white patients similar maximal drops of BP (mean+/-s.e.m.) were obtained with nifedipine-capsules (71+/-4/52+/-4 mm Hg) and with captopril (69+/-4/50+/-3 mm Hg). In black patients the maximal drop of BP of nifedipine-capsules (70+/-4/52+/-4 mm Hg) was greater (P < 0.02) than that of captopril (48+/-4/32+/-3 mm Hg) but similar to that of nifedipine-retard (71+/-4/49+/-4 mm Hg). However, in contrast to nifedipine-capsules and captopril, nifedipine-retard produced a slower drop in BP. The time of peak drop in BP of both nifedipine-capsules and captopril occurred within the first 2 h whereas with nifedipine-retard it occurred only between 4 and 6 h after administration. Fewer patients reported side effects with nifedipine-retard as compared with the other two preparations. We conclude that single doses of captopril and nifedipine reduces BP for at least 6 h in both white and black patients with hypertensive crisis, but nifedipine is more potent than captopril in black patients. The slow release form of nifedipine-retard effectively and safely lowers BP while achieving a rapid enough effect without the critical rapid falls in BP that occur with nifedipine-capsules.
Damasceno
A
A
Faculdade Medicina Universidade Eduardo Mondlane, Maputo, Mozambique.
Ferreira
B
B
Patel
S
S
Sevene
E
E
Polónia
J
J
D000284:Administration, Oral; D000328:Adult; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D044383:Black People; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D002216:Captopril / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D003692:Delayed-Action Preparations; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000208:ethnology; D008297:Male; D009543:Nifedipine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D012449:Safety; D016896:Treatment Outcome; D044465:White People
D000806:Angiotensin-Converting Enzyme Inhibitors; D002121:Calcium Channel Blockers; D003692:Delayed-Action Preparations; D002216:Captopril; D009543:Nifedipine