Health Topics for Mental and Emotional Health

Department of Psychiatry

Hallucinations

Hallucinations are sensations that are not real. Any of the senses can be involved. A person may see, hear, taste, smell, or feel something that is not there. Hallucinations can be frightening for the person experiencing them and for those near them. If you are with someone who is having hallucinations, keep calm and seek medical care as soon as possible.

There are many reasons for hallucinations. Many times the cause is easily detected and treated. Some of the causes for hallucinations include:

• some psychiatric disorders
• dehydration
• interaction of prescription medications
• severe lack of sleep
• use of drugs such as LSD, psilocybin mushrooms, or PCP
• heavy alcohol use and
• problems with the brain or nervous system

Illusions are different from hallucinations. Illusions involve misinterpreting something that is real. Everyone experiences illusions at some time. They are generally not a cause for concern. People with only partial vision or partial hearing often experience illusions. This is because human brains have a natural tendency to fill in missing gaps. For instance, it is not unusual for elderly people to mistake the hum of an air conditioner for the murmur of voices.

After someone dies, it is normal for people who were close to that person to see or hear that individual on occasion. This is generally not a concern unless it becomes distressing. Grief counseling can often help.

In post-traumatic stress disorder, people have experienced severe traumas such as rape or the events of war. They may have "flashbacks" where they see or feel these old events happening again. They may also have illusions where they distort reality. For instance, someone with post-traumatic stress disorder might see a police officer's uniform as a military uniform. Many forms of treatment are available to help people with post-traumatic stress disorder.

People who have lost an arm, a leg, or another body part often experience a special kind of physical hallucination. This is called a "phantom limb," where they feel sensation in the missing part. This is very common and treatments are available.

Hallucinations can be related to certain mental disorders, such as schizophrenia. However, the hallucinations can generally be controlled with proper medication. If you or someone you care about is having hallucinations, the first step is to get an accurate professional diagnosis.

Last Reviewed 2005

Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available.The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.

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