title: Comparative anti-hypertensive effects of labetalol and the combination of oxprenolol and phentolamine.
abstract: 1 The interaction of phentolamine with the beta-adrenoreceptor-blocking drug, oxprenolol, was studied in a controlled trial. 2 The combination was generally well tolerated. 3 Oxprenolol alone produced modest but significant reductions in supine, standing and post-exercise blood pressures. Small reductions were observed only with sustained phentolamine administration. 4 The combined effect of the two drugs seemed to be addictive only at the lower level of oxyprenolol dosage. 5 Labetalol produced significantly greater reductions in supine and standing blood pressure than combined oxprenolol-phentolamine. At a daily dose of 400 mg, postural hypotension was not observed, although transient symptoms were frequent.
mesh_terms: D000328:Adult; D000368:Aged; D000959:Antihypertensive Agents; D001794:Blood Pressure / Q000187:drug effects; D002986:Clinical Trials as Topic; D004305:Dose-Response Relationship, Drug; D004341:Drug Evaluation; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D004983:Ethanolamines / Q000627:therapeutic use*; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D007741:Labetalol / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010096:Oxprenolol / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D010646:Phentolamine / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D000959:Antihypertensive Agents; D004983:Ethanolamines; D010096:Oxprenolol; D007741:Labetalol; D010646:Phentolamine