Adverse effects of acebutolol in chronic stable angina: drug-induced positive antinuclear antibody.

Acebutolol, a cardioselective beta-adrenergic blocking agent, was administered for 48 weeks to 11 patients with chronic stable angina in a single-blind trial for determining efficacy and safety. As expected, beta-adrenergic blockade reduced angina frequency and improved exercise performance (p less than 0.001). Three patients developed an antinuclear antibody (ANA) titer, and in two patients a low titer present during placebo treatment increased fourfold. Two patients had joint symptoms probably related to acebutolol administration. Readministration of acebutolol after the ANA returned to negative resulted in a significant rise in ANA titer in two patients tested. The other nine patients tolerated long-term acebutolol therapy without significant side effects.