Usefulness of atypical antipsychotics and choline esterase inhibitors in delirium: a review

Delirium is characterized by disturbances of consciousness, attention, cognition, perception, emotions, sleep, and psychomotor activity. Management of delirium involves ensuring safety, improving functioning, identifying and treating the illness underlying the delirium, and use of antipsychotics or benzodiazepines to control behavioural symptoms and prevent mortality. Haloperidol continues to be the most commonly used antipsychotic in delirium. However, in recent times data have emerged which suggest that atypical antipsychotics may be as efficacious as haloperidol in the treatment of delirium. This review intends to review the data with respect to usefulness of atypical antipsychotics in the treatment of delirium. Besides atypical antipsychotics, data with respect to another group of medications - cholinesterase inhibitors are also reviewed. Electronic and manual searches were conducted to identify all the relevant studies and case reports/case series. Evidence suggests that risperidone, olanzapine and quetiapine are as efficacious as haloperidol in the treatment of delirium but have lesser side effects. Data for other atypical antipsychotics are scarce. The data on cholinesterase inhibitors for treatment and prevention of delirium are beginning to accumulate, but do not seem to be convincing. Our review suggests that risperidone, olanzapine and quetiapine are good alternatives to haloperidol in the treatment of delirium.