['A double-blind, placebo-controlled, randomized, crossover study was conducted to determine the effect of sertraline on the beta-adrenergic blocking activity of atenolol in 10 healthy male volunteers.', 'To assess the existence of any possible pharmacodynamic interaction between sertraline and atenolol, the effect of sertraline and placebo on the dose of intravenous isoproterenol required to increase heart rate by 25 beats per minute (bpm; chronotropic dose25 [CD25]) and the change in heart rate during exercise in atenolol-treated subjects were determined.', 'The mean CD25 of isoproterenol was 2.00 micrograms after administration of placebo plus atenolol 50 mg and 2.03 micrograms after administration of sertralnie 100 micrograms plus atenolol 50 mg. The mean heart rate during exercise testing decreased by 29 bpm after sertraline plus atenolol administration and by 31 bpm after placebo plus atenolol administration. Analysis of variance indicated no statistically significant treatment or sequence effects. Only 1 subject experienced an adverse event--a mild headache after administration of sertraline plus atenolol. No clinically significant electrocardiograph changes were observed after sertraline or placebo administration.'] Does sertraline alter the beta-adrenergic blocking activity of atenolol in healthy male volunteers?