Drug-induced delirium. Incidence, management and prevention.

Drugs may be the most frequent single cause of delirium, and very often they are a critical element in a multifactorial aetiology. While delirium may be precipitated by virtually any drug, certain classes of drugs are more commonly implicated. Effective management of drug-induced delirium involves recognition, cessation or dosage reduction of the causative drug(s), and initiation of reorientation strategies and supportive medical care. Specific "antidotes' are appropriate in only a few limited cases. Drug treatment aimed at sedation should be introduced for specific indications, such as aggression, risk of harm to self or others, hallucinations, patient distress, and where compliance with therapy or procedures is essential. Certain benzodiazepines (diazepam, lorazepam, midazolam) and/or haloperidol may be the most appropriate choices in these circumstances. Primary prevention requires the prescription of alternative lower risk medications and the minimisation of polypharmacy. Secondary prevention may be achieved through improved recognition of the condition.