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Behavioral Emergencies


Michael B. First

, MD, Columbia University

Reviewed/Revised May 2022 | Modified Dec 2022
Topic Resources

Patients who are experiencing severe changes in mood, thoughts, or behavior or severe, potentially life-threatening drug adverse effects need urgent assessment and treatment. Nonspecialists are often the first care providers for outpatients and inpatients on medical units, but whenever possible, such cases should also be evaluated by a psychiatrist.

When a patient’s mood, thoughts, or behavior is highly unusual or disorganized, assessment must first determine whether the patient is a

  • Threat to self

  • Threat to others

The threat to self can include inability to care for self (leading to self-neglect) or suicidal behavior Suicidal Behavior Suicide is death caused by an act of self-harm that is intended to be lethal. Suicidal behavior encompasses a spectrum of behavior from suicide attempt and preparatory behaviors to completed... read more . Self-neglect is a particular concern for patients with psychotic disorders, dementia, or substance use disorders because their ability to obtain food, clothing, and appropriate protection from the elements is impaired.

Patients posing a threat to others include those who

  • Are actively violent (ie, actively assaulting staff members, throwing and breaking things)

  • Appear belligerent and hostile (ie, potentially violent)

  • Do not appear threatening to the examiner and staff members but express intent to harm another person (eg, spouse, neighbor, public figure)

It is also important to identify caregivers who cannot safely and adequately care for their dependents.


Aggressive, violent patients are often psychotic and have diagnoses such as a substance use disorder Substance Use Disorders Substance use disorders involve a pathologic pattern of behaviors in which patients continue to use a substance despite experiencing significant problems related to its use. Diagnosis of substance... read more , schizophrenia Schizophrenia Schizophrenia is characterized by psychosis (loss of contact with reality), hallucinations (false perceptions), delusions (false beliefs), disorganized speech and behavior, flattened affect... read more , brief psychotic disorder Brief Psychotic Disorder Brief psychotic disorder consists of delusions, hallucinations, or other psychotic symptoms for at least 1 day but < 1 month, with eventual return to normal premorbid functioning. Brief psychotic... read more , delusional disorder Delusional Disorder Delusional disorder is characterized by firmly held false beliefs (delusions) that persist for at least 1 month, without other symptoms of psychosis. Delusions are distinguished from mistaken... read more , or acute mania Mania Bipolar disorders are characterized by alternating episodes of mania and depression, although many patients have a predominance of one or the other. Exact cause is unknown, but heredity, changes... read more . Other causes include physical disorders that cause acute delirium Delirium Delirium is an acute, transient, usually reversible, fluctuating disturbance in attention, cognition, and consciousness level. Causes include almost any disorder or drug. Diagnosis is clinical... read more (see Areas to Cover in the Initial Psychiatric Assessment Areas to Cover in the Initial Psychiatric Assessment Areas to Cover in the Initial Psychiatric Assessment ), dementia Dementia Dementia is chronic, global, usually irreversible deterioration of cognition. Diagnosis is clinical; laboratory and imaging tests are usually used to identify treatable causes. Treatment is... read more , and intoxication with alcohol Alcohol Toxicity and Withdrawal Alcohol (ethanol) is a central nervous system depressant. Large amounts consumed rapidly can cause respiratory depression, coma, and death. Large amounts chronically consumed damage the liver... read more or other substances, particularly methamphetamine Amphetamines Amphetamines are sympathomimetic drugs with central nervous system stimulant and euphoriant properties whose toxic adverse effects include delirium, hypertension, seizures, and hyperthermia... read more , cocaine Cocaine Cocaine is a sympathomimetic drug with central nervous system stimulant and euphoriant properties. High doses can cause panic, schizophrenic-like symptoms, seizures, hyperthermia, hypertension... read more , and sometimes phencyclidine Ketamine and Phencyclidine (PCP) Ketamine and phencyclidine are N-methyl-D-aspartate receptor antagonists and dissociative anesthetics that can cause intoxication, sometimes with confusion or a catatonic state. Overdose can... read more (PCP) and club drugs (eg, MDMA Methylenedioxymethamphetamine (MDMA) MDMA (3,4-methylenedioxymethamphetamine) is an amphetamine analog with stimulant and hallucinogenic effects. MDMA acts primarily on neurons that produce and release serotonin, but it also affects... read more [3,4-methylenedioxymethamphetamine]).

A prior history of violence or aggression is a strong predictor of future episodes.

General Principles

Management of behavioral emergencies typically occurs simultaneously with evaluation, particularly evaluation for a possible physical disorder (see Medical Assessment of the Patient With Mental Symptoms Medical Assessment of the Patient With Mental Symptoms Patients with mental complaints or concerns or disordered behavior present in a variety of clinical settings, including primary care and emergency treatment centers. Complaints or concerns may... read more ); it is a mistake to assume that the cause of abnormal behavior is a mental disorder or intoxication, even in patients who have a known psychiatric diagnosis or an odor of alcohol. Because patients are often unable or unwilling to provide a clear history, other collateral sources of information (eg, family members, friends, caseworkers, medical records) must be identified and consulted immediately.

Pearls & Pitfalls

  • Do not assume that the cause of abnormal behavior is a mental disorder or intoxication, even in patients who have a known psychiatric diagnosis or an odor of alcohol.

The clinician must be aware that patient violence may be directed at the treatment team and other patients.

Actively violent patients must first be restrained by

  • Physical means

  • Drugs (chemical restraint)

  • Both

Such interventions are done to prevent harm to patients and others and to allow evaluation of the cause of the behavior (eg, by taking vital signs and doing blood tests). Once the patient is restrained, close monitoring, sometimes involving constant observation by a trained sitter, is required. Medically stable patients may be placed in a safe seclusion room. Although clinicians must be aware of legal issues regarding involuntary treatment Legal Considerations Patients who are experiencing severe changes in mood, thoughts, or behavior or severe, potentially life-threatening drug adverse effects need urgent assessment and treatment. Nonspecialists... read more (see also Regulatory Issues in the Use of Physical Restraints in Aggressive, Violent Patients Regulatory Issues in Use of Physical Restraints in Aggressive, Violent Patients Regulatory Issues in Use of Physical Restraints in Aggressive, Violent Patients ), such issues must not delay potentially lifesaving interventions.

Potentially violent patients require measures to defuse the situation. Measures that may help reduce agitation and aggressiveness include

  • Moving patients to a calm, quiet environment (eg, a seclusion room, when available)

  • Removing objects that could be used to inflict harm to self or others

  • Expressing sympathetic concern for patients and their complaints

  • Responding in a confident yet supportive manner

  • Inquiring what can be done to resolve the cause of the agitation or aggressiveness

Speaking directly—mentioning that patients seem angry or upset, asking them if they intend to hurt someone—acknowledges their feelings and may elicit information; it does not make them more likely to act out.

Counterproductive measures include

  • Challenging the validity of patients’ fears and complaints

  • Issuing threats (eg, to call police, to commit them to a mental hospital)

  • Speaking in a condescending manner

  • Attempting to deceive patients (eg, hiding drugs in food, promising them they will not be restrained)

Staff and public safety

When hostile, aggressive patients are interviewed, staff safety must be considered. Most hospitals have a policy to search for weapons (manually, with metal detectors, or both) on patients presenting with disordered behavior. When possible, patients should be assessed in an area with safety features such as security cameras, metal detectors, and interview rooms that are visible to staff members.

Patients who are hostile but not yet violent typically do not assault staff members randomly; rather, they assault staff members who anger or appear threatening to them. Doors to rooms should be left open. Staff members may also avoid appearing threatening by sitting on the same level as patients. Staff members may avoid angering patients by not responding to their hostility in kind, with loud, angry remarks or arguing. If patients nonetheless become increasingly agitated and violence appears impending, staff members should simply leave the room and summon sufficient additional staff to provide a show of force, which sometimes deters patients. Typically, at least 4 or 5 people should be present (some preferably young and male). However, the team should not bring restraints into the room unless they are definitely to be applied; seeing restraints may further agitate patients.

Verbal threats must be taken seriously. In most states, when a patient expresses the intention to harm a particular person, the evaluating physician is required to warn the intended victim and to notify a specified law enforcement agency. Specific requirements vary by state. Typically, state regulations also require reporting of suspected abuse of children, older people, and spouses.

Physical Restraints

Use of physical restraints is controversial and should be considered only when other methods have failed and a patient continues to pose a significant risk of harm to self or others. Restraints may be needed to hold the patient long enough to administer drugs, do a complete assessment, or both. Because restraints are applied without the patient’s consent, certain legal and ethical issues should be considered (see Regulatory Issues in the Use of Physical Restraints in Aggressive, Violent Patients Regulatory Issues in Use of Physical Restraints in Aggressive, Violent Patients Regulatory Issues in Use of Physical Restraints in Aggressive, Violent Patients ).

Regulatory Issues in Use of Physical Restraints in Aggressive, Violent Patients

Use of physical restraints should be considered a last resort, when other steps have not sufficiently controlled aggressive, potentially violent behavior. When restraints are needed for such a situation, they are legal in all states as long as their use is properly ordered and documented in the patient’s medical record. Restraints have the advantage of being immediately removable, whereas drugs may alter symptoms enough or in a way that delays assessment.

The Joint Commission on Accreditation of Healthcare Organizations Standards on Restraint and Seclusion provides guidelines for use of restraints in the psychiatric setting. They state that restraints must be applied under the direction of a licensed practitioner (LP) who is authorized by hospital policy in accordance with state law to do so. The LP must assess the patient within the first hour of restraint placement. The order for continued restraint of adults may be written for up to 4 hours at a time. The patient must be evaluated by an LP or registered nurse during the 4-hour interval and before further continuation of the restraint order. After a minimum time interval, which is specified by state law and is no longer than 24 hours, the LP must reevaluate the patient in person before continuing the restraint order. Children aged 9‒17 years must be assessed every 2 hours, and those < 9 years, every hour.

Hospital accreditation standards require that patients in restraints be continuously observed by a trained sitter. Immediately after restraints have been applied, the patient must be monitored for signs of injury; circulation, range of motion, nutrition and hydration, vital signs, hygiene, and elimination are also monitored. Physical and mental comfort and readiness for discontinuation of restraints as appropriate are also assessed. These assessments should be done every 15 minutes.

Seclusion and restraints should be used simultaneously only under special circumstances and with continuous monitoring.

Restraints are used to

  • Prevent clear, imminent harm to the patient or others

  • Prevent the patient’s medical treatment from being significantly disrupted (eg, by pulling out tubes or IVs) when consent to the treatment has been provided

  • Prevent damage to physical surroundings, staff members, or other patients

  • Prevent a patient who requires involuntary treatment from leaving (when a locked room is unavailable)

Restraints should not be used for

  • Punishment

  • Convenience of staff members (eg, to prevent wandering)

Caution is required in overtly suicidal patients, who could use the restraint as a suicide device.


Restraints should be applied only by staff members adequately trained in correct techniques and in protecting patient rights and safety.

First, adequate staff are assembled in the room, and patients are informed that restraints must be applied. Patients are encouraged to cooperate to avoid a struggle. However, once the clinician has determined that restraints are necessary, there is no negotiation, and patients are told that restraints will be applied whether or not they agree. Some actually understand and appreciate having external limits on their behavior.

In preparation for applying restraints, one person is assigned to each extremity and another to the patient’s head. Then, each person simultaneously grasps their assigned extremity and places the patient supine on the bed; one physically fit person can typically control a single extremity of even large, violent patients (provided all extremities are grasped at the same time). However, an additional person is needed to apply the restraints. Rarely, upright patients who are extremely combative may first need to be sandwiched between 2 mattresses.

Leather restraints are preferred. One restraint is applied to each ankle and wrist and attached to the bed frame, not the rail. Restraints are not applied around the chest, neck, or head, and gags (eg, to prevent spitting and swearing) are forbidden. Patients who remain combative in restraints (eg, attempting to upset the stretcher, bite, or spit) may require chemical restraint.


Agitated or violent people brought to the hospital by police are almost always in restraints (eg, handcuffs). Occasionally, young, healthy people have died in police restraints before or shortly after hospital arrival. The cause is often unclear but probably involves some combination of overexertion with subsequent metabolic derangement and hyperthermia, drug use, aspiration of stomach contents into the respiratory system, embolism in people left in restraints for a long time, and occasionally serious underlying medical disorders. Death is more likely if people are restrained in the hobble position, with one or both wrists shackled to the ankles behind their back; this type of restraint may cause asphyxia and should be avoided. Because of these complications, violent patients presenting in police custody should be evaluated promptly and thoroughly and not dismissed as mere sociobehavioral problems.

Chemical Restraints

Drug therapy, if used, should target control of specific symptoms.


Patients can usually be rapidly calmed or tranquilized using

  • Benzodiazepines

  • Antipsychotics (typically a conventional antipsychotic, but a 2nd-generation drug may be used)

These drugs are better titrated and act more rapidly and reliably when administered IV (see table Drug Therapy for Agitated or Violent Patients Drug Therapy for Agitated or Violent Patients Drug Therapy for Agitated or Violent Patients ), but IM administration may be necessary when IV access cannot be achieved in struggling patients. Both classes of drug are effective sedatives for agitated, violent patients. Benzodiazepines are probably preferred for stimulant drug overdoses and for alcohol and benzodiazepine drug withdrawal syndromes, and antipsychotics are preferred for clear exacerbations of known mental disorders. Sometimes a combination of both drugs is more effective; when large doses of one drug have not had the full desired effect, using another drug class instead of continuing to increase the dose of the first drug may limit adverse effects.


Adverse effects of benzodiazepines

Parenteral benzodiazepines, particularly in the doses sometimes needed for extremely violent patients, may cause respiratory depression. Airway management Airway Establishment and Control Airway management consists of Clearing the upper airway Maintaining an open air passage with a mechanical device Sometimes assisting respirations (See also Overview of Respiratory Arrest.) read more with intubation and assisted ventilation may be required. The benzodiazepine antagonist, flumazenil, may be used, but caution is required because if sedation is significantly reversed, the original behavioral problem may reappear.

Benzodiazepines sometimes lead to further disinhibition of behavior.

Adverse effects of antipsychotic drugs

Antipsychotics, particularly dopamine-receptor antagonists, at therapeutic as well as toxic doses, can have acute extrapyramidal adverse effects (see table Treatment of Acute Adverse Effects of Antipsychotics Treatment of Acute Adverse Effects of Antipsychotics Treatment of Acute Adverse Effects of Antipsychotics ), including acute dystonia and akathisia (an unpleasant sensation of motor restlessness). These adverse effects may be dose dependent and may resolve once the drug is stopped.

Several antipsychotics, including thioridazine, haloperidol, droperidol, olanzapine, risperidone, and ziprasidone, can cause long QT interval syndrome and ultimately increase the risk of fatal arrhythmias. Neuroleptic malignant syndrome Neuroleptic Malignant Syndrome Neuroleptic malignant syndrome is characterized by altered mental status, muscle rigidity, hyperthermia, and autonomic hyperactivity that occur when certain neuroleptic drugs are used. Clinically... read more is also a possibility.


Legal Considerations

Patients with severe changes in mood, thoughts, or behavior are usually hospitalized when their condition is likely to deteriorate without psychiatric intervention and when appropriate alternatives are not available.

Consent and involuntary treatment

If patients refuse hospitalization, the physician must decide whether to hold them against their will. Doing so may be necessary to ensure the immediate safety of the patient or of others or to allow completion of an assessment and implementation of treatment.

Criteria and procedures for involuntary hospitalization vary by jurisdiction. Usually, involuntary hospitalization requires a physician or psychologist and one additional clinician, family member, or close contact to certify that the patient has a mental disorder, is a danger to self or to others, and refuses voluntary treatment. Physicians should obtain consent to drug treatment of minor children from parents or guardians.

Danger to self includes but is not limited to

In most jurisdictions, knowledge of intent to commit suicide requires a health care practitioner to act immediately to prevent the suicide, for example, by notifying the police or another responsible agency.

Danger to others includes

  • Expressing homicidal intent

  • Placing others in peril

  • Failing to provide for the needs or safety of dependents because of the mental disorder

Drugs Mentioned In This Article

Drug Name Select Trade
Mellaril, Mellaril Concentrate , Mellaril-S
Haldol, Haldol Decanoate
Zyprexa, Zyprexa Intramuscular, Zyprexa Relprevv, Zyprexa Zydis
PERSERIS, Risperdal, Risperdal Consta, Risperdal M-Tab, Rykindo, UZEDY
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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