Medically Reviewed By William C. Lloyd III, MD, FACS

What are hallucinations?

Hallucinations are sensations or perceptions that occur in a wakeful state and seem real, but are not. The brain creates hallucinations, but they carry the same effects on people as reality. Hallucinations may be seen, heard, smelled, felt or tasted. They can be pleasant or threatening and may be related to sensations, imagery, or events of the past, or they may be unrelated to experiences. Common hallucinations include hearing voices; seeing objects, lights or people who are not there; and the sensation of crawling skin.

Hallucinations are different from delusions, vision changes, and dreams. Delusions are thoughts or conclusions that do not have a basis in reality. The easiest way to explain hallucinations vs. delusions are that hallucinations are false perceptions; delusions are false beliefs. Vision changes, such as floaters, spots, and flashes of light, are due to conditions of the eye. Dreams occur while you are asleep.

Hallucinations are symptoms of some psychiatric disorders or medical conditions. Auditory hallucinations are most common. Psychiatric conditions with hallucinations include schizophrenia, schizoid and schizotypal personality disorders, psychotic depression, and bipolar disorder. Medical conditions affecting the central nervous system, such as brain tumors, delirium, dementia, epilepsy and other seizure disorders, and stroke, can cause hallucinations. Hallucinations can also occur with high fevers.

Some people abuse certain medications and substances because those items can cause hallucinations. Other substances, such as alcohol, can cause hallucinations when used in large quantities or during withdrawal. Hallucinations can be side effects of some medications and may occur with visual or hearing loss. Sleep deprivation or severe fatigue are also hallucinations causes.

Hallucinations can be symptoms of serious and even life-threatening conditions. Seek immediate medical care (call 911) if you, or someone you are with, experience hallucinations that cannot be distinguished from reality, or hallucinations that are accompanied by:

  • Bluish coloration of the lips or fingernails

  • Chest pain or pressure

  • Cold, clammy or dry, hot skin

  • Confusion or loss of consciousness for even a moment

  • High fever (higher than 101°F)

  • Persistent vomiting 

  • Rapid, slow or absent pulse 

  • Respiratory or breathing problems, such as rapid or slow breathing, shortness of breath, or no breathing

  • Seizure 

  • Serious injury 

  • Severe abdominal pain 

  • Threatening, irrational or suicidal behavior

Seek prompt medical care if you are being treated for a condition that causes hallucinations and your symptoms are persistent, worsen, or otherwise cause you concern.

What are the different types of hallucinations?

The types of hallucinations relate to the senses and can include:

  • Auditory hallucinations are hearing voices or sounds, such as music, that are not there. These are the most common types of hallucination.

  • Gustatory hallucinations are tasting something that you have not ingested.

  • Olfactory hallucinations are smelling things that are not real.

  • Tactile hallucinations are feeling sensations that have no real physical stimuli.

  • Visual hallucinations are seeing things that are not there.

Even though the various types of hallucinations occur without external stimuli, they are very real to the person experiencing them.

What other symptoms might occur with hallucinations?

Hallucinations may accompany other symptoms that vary depending on the underlying disease, disorder or condition. Symptoms that frequently affect the brain may also involve other body systems.

Psychological and cognitive symptoms that may occur along with hallucinations

Hallucinations may accompany other psychological or cognitive symptoms including:

  • Anxiety, irritability or agitation

  • Changes in mood, personality or behavior

  • Confusion, forgetfulness or disconnectedness

  • Delusions

  • Difficulty with memory, thinking, talking, comprehension, writing or reading

  • Heightened arousal or awareness

  • Mood depression or elevation

  • Mood instability

  • Poor judgment

  • Sleep disturbances

  • Withdrawal or depression

Other symptoms that may occur along with hallucinations

Hallucinations may accompany symptoms related to other body systems including:

Serious symptoms that might indicate a life-threatening condition

In some cases, hallucinations may be a symptom of a life-threatening condition that should be immediately evaluated in an emergency setting. Seek immediate medical care (call 911) if you, or someone you are with, have any of these life-threatening symptoms including:

  • Being a danger to oneself or others, including threatening, irrational or suicidal behavior

  • Bluish coloration of the lips or fingernails

  • Change in level of consciousness or alertness, such as passing out or unresponsiveness

  • Change in mental status or sudden behavior change, such as confusion, delirium, lethargy, hallucinations and delusions

  • Chest pain, chest tightness, chest pressure, palpitations

  • High fever (higher than 101°F)

  • Rapid heart rate (tachycardia), slow heart rate (bradycardia), or abnormal heart rhythms (arrhythmias)

  • Respiratory or breathing problems, such as shortness of breath, difficulty breathing, labored breathing, slow breathing, not breathing, choking

  • Seizure

  • Severe and persistent vomiting

  • Severe pain

  • Trauma, such as bone deformity, burns, eye injuries, and other injuries

What causes hallucinations?

The specific cause of hallucinations is not known, but they can be associated with some psychiatric disorders or medical conditions. Substance abuse and withdrawal, medication side effects, sensory loss, sleep deprivation, and severe fatigue can all be associated with hallucinations.

Psychiatric causes of hallucinations

Hallucinations may be caused by psychiatric conditions including:

Other causes of hallucinations

Hallucinations can have other causes including:

  • Brain tumors

  • Delirium

  • Dementia

  • Medication side effects

  • Seizure disorders

  • Severe fatigue

  • Sleep deprivation

  • Substance abuse

  • Vision or hearing loss

Serious or life-threatening causes of hallucinations

In some cases, hallucinations may be a symptom of a serious or life-threatening condition that should be immediately evaluated in an emergency setting. These include:

  • Acute delirium (sudden onset of mental status changes due to illness or toxicity)

  • Seizures

  • Severe infections

  • Stroke

When should you see a doctor for hallucinations?

Hallucinating is a reason for immediate medical care. Both psychiatric and medical conditions can cause hallucinations. In either case, the situation can become an emergency very quickly. Call 911 or go to your nearest emergency room any time someone is experiencing hallucinations.

How do doctors diagnose the cause of hallucinations?

To diagnose the cause of hallucinations, your doctor will take a medical history, perform an exam, and may order testing.

Questions for diagnosing the cause of hallucinations

There are several questions your doctor may ask related to your hallucinations including:

  • When did you first experience hallucinations?
  • What types of hallucinations are you having?
  • Can you describe your hallucinations?
  • Did any events or stresses precede your hallucinations?
  • Do you have any other symptoms?
  • What medical, mental or psychiatric problems do you have?
  • What medications are you taking?
  • Do you drink any alcohol?
  • Are you using any illicit drugs?

Exams and testing for diagnosing the cause of hallucinations

During the physical exam, your doctor will focus on ruling out physical conditions that could be causing hallucinations. If there is no medical or physical reason for the hallucinations, a psychiatric evaluation may be necessary. Input from family members is often helpful in understanding the situation. To diagnose mental disorders, doctors use diagnostic criteria set forth in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) from the American Psychiatric Association.

In some cases, doctors may order testing to help diagnose the cause of hallucinations. This mainly involves blood tests to screen for alcohol and drugs and imaging exams, such as a brain CT (computerized tomography) scan or MRI (magnetic resonance imaging).

It is not always possible to diagnose an underlying cause or condition. If the problem persists and your provider is unable to determine a cause, seeking a second opinion may give you more information and answers.

What are the treatments for hallucinations?

Treating hallucinations depends entirely on the underlying cause. When schizophrenia or another mental health problem is to blame, medications are an important part of treatment. The goal is to control the symptoms of the disorder with the lowest possible dose.

Second-generation antipsychotics, such as aripiprazole (Abilify) or quetiapine (Seroquel), are the first-line choice. These drugs tend to have fewer side effects than earlier versions of antipsychotic medicines. It is also important for people with these conditions to avoid illicit drugs, nicotine and alcohol. These substances can make it harder to treat the underlying mental health problem.

Psychosocial interventions are also part of treatment for mental health issues. This includes psychotherapy, family therapy, and social skills and vocational training.

For people with hallucinations due to Alzheimer’s disease, behavioral approaches are usually first-line treatment. If these strategies fail, medications may be necessary. However, the use of antipsychotics in older people with dementia carries an increased risk of death. Only an experienced doctor should prescribe antipsychotics in this situation. It is very important to carefully weigh the risks and benefits of this treatment in this population.

Home remedies for hallucinations

Home remedies cannot treat hallucinations. But there are several things caregivers and those around someone who is hallucinating can do to help the situation. This includes:

  • Do not argue with the person or try to convince them that the experience is not real. Convey reassurance and understanding instead.
  • Make sure the person is safe by removing anything they could use to hurt themselves or others.
  • Remain calm and offer comfort. Fear usually drives reactions to hallucinations.
  • Remove upsetting stimuli, such as turning off a violent TV show or changing lighting that may be casting shadows.
  • Use distraction, such as going for a walk or moving to another room.

Alternative treatments for hallucinations

For people with schizophrenia or other psychiatric causes of hallucinations, it can be helpful to practice relaxation techniques. Try meditation or another mind-body technique to reduce stress and promote healthy thoughts.

What are the potential complications of hallucinations?

Because hallucinations can be due to serious diseases, failure to seek treatment can result in serious complications and permanent damage. Once the underlying cause is diagnosed, it is important for you to follow the treatment plan that you and your health care professional design specifically for you to reduce the risk of potential complications including:

  • Brain damage

  • Coma

  • Difficulties at work, in school, in social environments, and with relationships

  • Drug and alcohol use and abuse

  • Drug overdose or alcohol poisoning

  • Increased risk of injury

  • Legal or financial troubles

  • Self-harm

  • Suicide or violence
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  1. Alzheimer’s and Hallucinations, Delusions, and Paranoia. National Institute on Aging. https://www.nia.nih.gov/health/alzheimers-and-hallucinations-delusions-and-paranoia
  2. Alzheimer's Disease: The Top Five Tips for Managing Hallucinations and Delusions. Bright Focus Foundation. https://www.brightfocus.org/alzheimers/article/alzheimers-disease-top-five-tips-managing-hallucinations-and-delusions
  3. Delirium. Mayo Foundation for Medical Education and Research. https://www.mayoclinic.org/diseases-conditions/delirium/symptoms-causes/syc-20371386
  4. Hallucinations. Alzheimer’s Association. https://www.alz.org/help-support/caregiving/stages-behaviors/hallucinations
  5. Hallucinations. MedlinePlus, National Library of Medicine National Institutes of Health. http://www.nlm.nih.gov/medlineplus/ency/article/003258.htm
  6. Patkar AA, Mago R, Masand PS. Psychotic symptoms in patients with medical disorders. Curr Psychiatry Rep 2004; 6:216.
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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2021 Jul 1
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