The use of atypical antipsychotic agents is associated with the induction of both an indolent progression to insulin-resistant diabetes and an idiosyncratic beta-cell toxicity presenting as diabetic ketoacidosis, both of which are usually reversible or improved subsequent to cessation of treatment. The underlying mechanisms are unclear at present. Nonetheless, in light of the now numerous reports on the adverse metabolic effects of these drugs, the Consensus Development Conference which met in November 2003 recommends that metabolic risks be considered when starting atypical antipsychotic drugs. Their operative checklist includes baseline screening of candidates for antipsychotic treatment, which includes personal/family history of diabetes, weight, waist circumference, blood pressure, fasting plasma glucose and fasting lipid profile, and then follow-up of these parameters. Furthermore, the health professionals, patients, family and caregivers should be aware of the signs and symptoms of diabetes, especially when acute decompensation occurs which is commensurate with diabetic ketoacidosis. We wish, through this short report, to raise the awareness of physicians treating psychiatric patients to the possibility of new-onset diabetes during therapy with atypical antipsychotic drugs and to emphasize the necessity for increased vigilance and close metabolic follow-up of these patients. Moreover, the choice of the best antipsychotic treatment for each patient should take into consideration the diabetogenic effect of the different treatment options as well the other side effects.