Antipsychotic drug doses and neuroleptic/dopamine receptors

ANTIPSYCHOTIC drugs, or neuroleptics, are thought to act by blocking dopamine receptors in the nervous system1–4. Recent direct evidence, based on stereospecific binding assays, supports this hypothesis of antipsychotic drug action5–9. As only a few antipsychotic drugs had been tested for their effects on the binding of haloperidol5–8, the question remained whether all antipsychotic drugs, regardless of chemical structure, would block the stereospecific binding of haloperidol. We report here that all clinically effective antipsychotic drugs (tested so far) block the stereo-specific binding of 3H-haloperidol at concentrations which correlate directly with the clinical potencies.