Rapid-acting intramuscular (IM) formulations of atypical antipsychotics offer a significant advance over IM haloperidol in the short-term management of acute schizophrenic episodes. Several short-term open-label randomised studies, typically enrolling two- to three-hundred patients, have compared an atypical antipsychotic with haloperidol. These studies show that IM ziprasidone, IM olanzapine and IM aripiprazole are at least as effective and better tolerated than IM haloperidol, with lower extrapyramidal side effects. Successful transitions from an IM to oral formulation of the same agent have been performed in double-blind randomised trials assessing haloperidol, olanzapine, ziprasidone and aripiprazole. Avoiding over-sedation is now recognised as important, and randomised clinical trial data indicate that oral ziprasone, quetiapine, and IM olanzapine have high dose-related sedative potential while oral risperidone and IM aripiprazole have low sedative potential. In summary, IM formulations of atypical antipsychotics are recommended as first-line treatment of acute agitation with subsequent transition to an oral formulation of the same agent for ongoing management.