Lack of efficacy of d-propranolol in neuroleptic-induced akathisia.

d-Propranolol lacks clinically significant beta-adrenergic receptor blocking properties, but has the same membrane stabilizing effects as racemic (d,l) propranolol. To assess the role of beta-blockade versus membrane stabilization or other shared nonspecific effects in the therapeutic action of propranolol in neuroleptic-induced akathisia (NIA) we treated 11 patients with NIA in a crossover, double-blind study of d-propranolol versus placebo. Akathisia scores were unchanged after both d-propranolol and placebo. Eight patients were subsequently treated in a nonblind manner with racemic propranolol, with a significant reduction in akathisia scores. These findings suggest that beta-blockade, not membrane stabilization or other shared nonspecific effects, contributes to the efficacy of propranolol in NIA.