brl-26830a and Tremor

Beta-adrenoceptor agonists have recently been shown to promote substantial loss of adipose tissue in laboratory animals. One of these BRL, 26830A, increases thermogenesis in human volunteers and has been shown to enhance the rate of weight reduction in patients adhering to a strict reducing regimen. Forty-three post-menopausal or sterilized female subjects suffering from refractory obesity participated in a double-blind placebo-controlled study, the treatment group receiving BRL 26830A 50 mg qid. Two subjects were withdrawn because they developed an unpleasant sensation of tremor and in all, 17 of the 20 who received BRL 26830A mentioned this side effect. There was no change in erect or supine blood pressure or in resting heart rate. There was no significant difference in weight change during the 6-week study. It is concluded that BRL 26830A does not appear to promote weight reduction in subjects unable to adhere strictly to their dietary regime.

Topics: Adrenergic beta-Agonists; Adult; Aged; Blood Pressure; Body Temperature Regulation; Double-Blind Method; Ethanolamines; Female; Humans; Middle Aged; Obesity; Random Allocation; Tremor

The thermogenic beta 3-adrenoceptor agonist BRL 26830A has been shown to increase weight loss in dieting subjects but tremor was a frequent adverse effect. We have investigated the magnitude and nature of this tremor after a single oral dose in 18 subjects. Two complementary techniques were used to attach the recording apparatus to the subjects to give both isotonic and isometric measures of tremor. Increases of 84% and 40% respectively were found due to exaggeration of physiological tremor presumably mediated through concomitant beta 2-adrenoceptor stimulation. The use of beta 3-adrenoceptor agonist drugs in the treatment of obesity may increase but the development of an agent without tremor inducing properties would be an obvious advantage.

Topics: Adrenergic beta-Agonists; Ethanolamines; Humans; Obesity; Receptors, Adrenergic, beta; Tremor