Antipsychotic drugs

Antipsychotic drugs can be classified by chemical structure and receptor specificity. Older phenothiazine antipsychotics act on a wide range of receptor systems, whereas the newer butyrophenone and atypical drugs are more specific, particularly at dopamine receptors. In overdose, adverse events include acute extrapyramidal reactions, sedation and cardiovascular effects including, potentially, arrhythmias. Phenothiazine antipsychotics often have anticholinergic, antihistamine and α-adrenoceptor antagonist activity, resulting in greater toxicity in overdose.