title: Dose related efficacy of betaxolol in combination with nitroglycerin in patients with angina pectoris: a double blind cross-over study.
abstract: The effect of three different oral doses, 5 mg, 10 mg and 20 mg of betaxolol (BTX), a new long acting cardioselective beta-adrenergic blocking drug, on exercise tolerance was studied in a randomized double blind, cross-over study with latin square distribution in nine male patients with angina pectoris, under continuous therapy with oral nitroglycerin. BTX caused a significant reduction of heart rate (p less than 0.001) for all different dose levels during exercise. Systolic blood pressure was significantly decreased at peak exercise for BTX 10 (p less than 0.01) and BTX 20 (p less than 0.001). During the three treatment periods a significant drop of the rate pressure product (p less than 0.01) was observed and a statistically significant improvement of exercise tolerance, before the occurrence of anginal pain, could be demonstrated. No differences could be detected in oxygen uptake, carbon dioxide output and ventilation between placebo- and treatment periods. BTX was well tolerated in all patients and exerted its effect also in the presence of nitroglycerin. Its cardioselectivity, ease of dosing and complete absence of side effects makes BTX an attractive choice as antianginal agent for chronic use.
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000097:blood / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000787:Angina Pectoris / Q000188:drug therapy* / Q000503:physiopathology; D015784:Betaxolol; D002986:Clinical Trials as Topic; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D004361:Drug Tolerance; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000627:therapeutic use*; D005082:Physical Exertion; D011412:Propanolamines / Q000097:blood / Q000627:therapeutic use*; D011897:Random Allocation; D012119:Respiration / Q000187:drug effects
chemical_list: D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D005996:Nitroglycerin; D015784:Betaxolol