Delirium, Dementia, and Amnesia in Emergency Medicine Medication

Updated: Sep 19, 2018
  • Author: Richard D Shin, MD, FACEP; Chief Editor: Gil Z Shlamovitz, MD, FACEP  more...
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Medication Summary

Medications typically used in the ED treatment of delirium or acute mental status changes include sedatives, neuroleptics and specific antidotes. Other drugs may be useful in treating specific etiologies uncovered in the workup. The medications outlined here are used for acute behavioral changes.



Class Summary

These agents are used to calm acute agitation, to control the behavior of combative patients, and to facilitate procedures.

Lorazepam (Ativan)

Commonly used Benzodiazepine in ED. Safe for a wide variety of acute behavioral disturbances. Can be given PO/SL (for rapid effect in panic attack)/IV/IM and can be mixed in syringe with neuroleptic agent. Sedative hypnotic with short onset of effects and relatively long duration of action. By increasing action of GABA, a major inhibitory neurotransmitter in the brain, may depress all levels of CNS, including limbic and reticular formation. When patient needs to be sedated for longer than 24-h period, this medication is excellent. Has longer CNS effect than diazepam and is preferred for seizure control. Easily titrated for acute withdrawal syndromes (eg, alcohol, benzodiazepines, barbiturates) and status seizures when given IV (10 mg or more may be needed in status epilepticus). Two mg of lorazepam approximately equivalent to 5 mg of diazepam. Preferred over neuroleptics for treating toxic effects of hallucinogens, cocaine, stimulants, or PCP.


Benzodiazepine with rapid onset of action, effective for acute agitation. Excellent choice to calm a combative/agitated patient with rapid onset and relatively short duration of action.

Onset of action: IM: Sedation: Children: Within 5 minutes; Adults: ~15 minutes; IV: 3 to 5 minutes

A prospective observational study demonstrated intramuscular midazolam achieved more effective sedation in agitated ED patients at 15 minutes than haloperidol, ziprasidone, and perhaps olanzapine.


Glucose supplements

Class Summary

Monosaccharides absorbed from intestine after PO absorption of dextrose results in rapid increase of blood glucose concentrations.


Should be given to any obtunded patient in whom hypoglycemia cannot be rapidly ruled out via bedside testing. Monosaccharide, absorbed from intestine and distributed, stored, and used by tissues. Parenterally injected dextrose is used in patients unable to obtain adequate PO intake; direct PO absorption results in rapid increase of blood glucose concentrations.

Serves to restore blood glucose levels. Each 100 mL of 5% dextrose contains 5 g of dextrose while each 100 mL of 10% dextrose contains 10 g of dextrose.

Effective in small doses; no evidence indicates that it may cause toxicity; concentrated infusions provide higher amounts of glucose and increased caloric intake with minimum fluid volume.



Class Summary

These agents have more robust calming effects than benzodiazepines in acutely agitated patients. They act fast when given IV. They can be mixed in the same syringe with lorazepam for rapid chemical restraint (IM/IV). They are easily titrated and long acting.

Haloperidol and droperidol are of the butyrophenone class, which is noted for high potency and low potential for orthostasis. However, they have great potential for extrapyramidal symptoms (EPS)/dystonia.

Caveat: Neuroleptics can mask the signs of withdrawal from alcohol, benzodiazepines, and barbiturates while failing to treat adrenergic and GABA-nergic dysregulation. They do not prevent seizures.

Haloperidol (Haldol)

DOC for severe agitation, acute psychosis, and severe delirium when no contraindications exist. Parenteral dosage form may be admixed in same syringe with 2 mg lorazepam for better anxiolytic effects.


Some clinicians believe droperidol is DOC for control of severely disturbed and/or violent patient. Somewhat faster acting and more sedating than haloperidol, but more likely to cause hypotension. May exert antipsychotic activity through dopaminergic system. May alter dopamine action in CNS. Parenteral dosage form may be admixed in same syringe with 2 mg lorazepam for better anxiolytic effects.

Now has black-box warning regarding life-threatening torsade de pointes (TdP) (a rhythmic pattern of sinusoidal ventricular complexes that leads to ventricular fibrillation and cardiac arrest), especially in the setting of prolonged QT syndrome. Assessing QT interval via ECG or rhythm strip advised before administering droperidol.


Atypical antipsychotics

Class Summary

These are newer neuroleptics with a lowered risk of extrapyramidal syndrome (EPS) and improved efficacy for the negative symptoms (eg, withdrawal, apathy) of psychosis because of their enhanced serotonergic activity as compared to older-style neuroleptics. These medications have largely supplanted older neuroleptics for sedation and treatment of psychosis in elderly patients with dementia.


Indicated for acute behavioral control in setting of acute psychosis, delirium, and as "chemical restraint." Less likely to cause severe dystonic reactions in younger patients than haloperidol and droperidol.

Risperidone (Risperdal)

Often used for sundowning in elderly patients but can increase mortality rate in dementia. Binds to dopamine D2 receptor with 20 times lower affinity than for serotonin 5-HT2 receptor. Improves negative symptoms of psychoses and reduces incidence of EPS. Also may have antidepressant effects, probably because of its serotonin activity.

Olanzapine (Zyprexa, Zyprexa Relprevv, Zyprexa Zydis)

Atypical antipsychotic that can be used for acute agitation. A prospective observational study revealed IM Olanzapine resulted in a greater proportion of patients adequately sedated at 15 minutes compared with IM haloperidol 5 mg, IM haloperidol 10 mg, and IM ziprasidone.



Class Summary

These agents are used when the toxic agent is known and has an antidote or as a coma cocktail in patients who are stuporous or comatose. Includes oxygen, thiamine (100 mg IV/IM), glucose (50 mL of D50W IV push), and naloxone (Narcan; 2-10 mg SC/IM/IV or via ETT). The use of flumazenil (Romazicon) for suspected or known benzodiazepine overdose is controversial. Flumazenil may precipitate refractory seizures in the setting of long-term use or mixed overdose with seizure-inducing agents (eg, TCAs). It may be useful in diagnosis and in avoiding the need for intubation.


In setting of suspected antihistaminic/anticholinergic overdose, increased concentration of acetylcholine can improve patient's delirium dramatically; for reasons that are not entirely clear, appears to have less effect if administered within 4 h postexposure. May be useful diagnostically. Avoid in suspected TCA OD.

Naloxone (Narcan, Evzio)

Prevents or reverses opioid effects (hypotension, respiratory depression, sedation), possibly by displacing opiates from their receptors.