title: Acute effect of intravenous labetalol in the treatment of systemic arterial hypertension.
abstract: 1 The acute anti-hypertensive effect of intravenously administered labetalol, a combined alpha- and beta-adrenoreceptor antagonist, has been assessed in a pilot study involving 17 hypertensive patients. 2 In 11 patients with mild to moderately severe hypertension, there was a decrease in mean arterial pressure (24 mmHg) after a single intravenous dose of 50 mg labetalol. The peak response occurred approximately 4 min after administration of the drug. 3 In six patients with severe hypertension, there was a reduction in mean arterial pressure of 19 mmHg, but this was achieved after a further 50-mg dose administered 30 min after the initial injection. 4 In neither group was there any clinically significant decrease in heart rate, and drug-related side-effects were insignificant. 5 Labetalol reduced the blood pressure when administered intravenously and thus merits further investigation as a treatment for acute hypertensive crises.
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects*; D004334:Drug Administration Schedule; D004341:Drug Evaluation; D004983:Ethanolamines / Q000494:pharmacology*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000503:physiopathology*; D007275:Injections, Intravenous; D007741:Labetalol / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged
chemical_list: D004983:Ethanolamines; D007741:Labetalol