Management
Treatment
The management of delirium centers on identifying and addressing the causative medical factors. Work-up should explore potential infectious, metabolic, neurologic, and biochemical causes. Imaging of the head may be indicated. In more than half of delirium cases, no definitive etiology can be identified. In these instances, care is supportive.
Behavioral management
Delirious patients should be managed in a setting of moderate stimulation. As much as possible, they should be provided with appropriate environmental cues: lights should be shut off during the night; they should be frequently reminded of the day and date, and, if possible, should be surrounded by family and other familiar faces. Their safety must be guarded, and close observation may be required. Some afflicted patients may lie listlessly, whereas others may become agitated and even violent. In these instances, chemical and even physical restraints may be required.
Medications
Antipsychotics
If more conservative measures are ineffective, pharmacotherapy may be required to manage the behavioral disturbances associated with delirium. Anti-psychotic medications may help to treat 
sensory misperceptions, as well as provide a degree of anxiolysis. Table 3 lists selected drugs often used to treat delirium in cancer patients. Because of a growing understanding of the health risks associated with use of these drugs (ranging from extrapyramidal symptoms to hyperglycemia, stroke, and increased risk of death in the elderly), antipsychotics should be reserved for use in patients with hyperactivity, for instance those who pull out blood access lines or those who wander.
Haloperidol is a potent antipsychotic that may be administered PO, IM, or IV. The IV formulation is twice as potent as the PO preparation.
Side effects Haloperidol is usually well tolerated, although it does carry a risk of akathisia and Parkinsonian side effects. The risk of these adverse reactions can be minimized by IV administration.
Dosage Elderly patients or patients with end-stage disease usually require very modest doses (0.5 to 1.0 mg PO or IV at night or twice daily) to control delirium. Especially in hyperactive delirium, higher and more frequent dosing is usually required (ie, 2 to 5 mg IV every 6 hours). In unusual cases, total doses of ≥ 50 mg/d may be administered via continuous infusion.
Risperidone is given orally. At doses of 0.5 to 3.0 mg once or twice daily, it is useful in managing delirium or delusional symptoms, especially in elderly patients, in whom it may have fewer adverse effects than oral haloperidol(Drug information on haloperidol).
Olanzapine has been shown to be effective in the management of delirious cancer patients and is available for administration PO or IM in cases of severe agitation. The Zydis formulation of olanzapine(Drug information on olanzapine) is an orally disintegrating tablet that easily dissolves in the mouth and may be useful for some agitated patients and for those with swallowing difficulties.
Quetiapine is fairly sedating and is an attractive option for treatment of low-intensity delirium, especially when given at night to control behavior and promote sleep.
