Hallucinations can be frightening and confusing for both the person experiencing them and their loved ones. Most people associate this condition with serious mental health conditions; they can also occur during substance use, withdrawal, medical illnesses, sleep deprivation, or certain neurological disorders. Understanding why hallucinations happen and when to seek immediate medical attention can help improve safety and support recovery.
What is a Hallucination?
A hallucination is a sensory experience that feels real but is not. This experience occurs without an external stimulus. Unlike imagination or daydreaming, hallucinations are perceived as genuine experiences.
Hallucinations can affect any of the senses:
- Auditory: Hearing voices, music, or sounds that are not present.
- Visual: Seeing things that are not there.
- Tactile: Feeling sensations such as bugs crawling on the skin or being touched.
- Olfactory: Smelling odors that have no external source.
- Gustatory: Tasting something that is not actually in the mouth.
Some people experience only one type of hallucination, while others may experience multiple types at the same time.
How the Brain Creates Hallucinations
The brain constantly processes information received through the senses. It interprets sights, sounds, smells, and other sensory input to help us understand the world. Hallucinations can occur when this process is disrupted. Changes in brain chemistry, communication between brain cells, or activity in specific areas of the brain may cause the brain to perceive sensations that are not actually occurring. When the brain’s chemical messengers become imbalanced due to illness, substance use, or withdrawal, hallucinations may occur.
Hallucinations and Substance Use
Many substances can affect the brain in ways that increase the risk.
Examples include:
- Alcohol
- Methamphetamine
- Cocaine
- LSD and other hallucinogens
- Psilocybin (“magic mushrooms”)
- PCP
- Ketamine
- Cannabis
Some drugs directly alter perception and can cause immediate hallucinations. Other substances may lead to this experience after prolonged use or during withdrawal. So many factors lead to the likelihood of experiencing hallucinations, like the substance used, dosage, duration of use, overall health, and whether multiple substances are used together.
Why Hallucinations Occur During Withdrawal
People can be particularly vulnerable to hallucinations during withdrawal. Withdrawal from alcohol or sedative drugs like benzodiazepines only increases the risk. During this time, the central nervous system slows in response to the substance. The brain responds by increasing excitatory activity to maintain balance. When the substance is suddenly stopped, the brain can become temporarily overactive.
This overstimulation may lead to anxiety, tremors, sweating, insomnia, confusion, seizures, and hallucinations. Alcohol withdrawal hallucinations may occur within the first day after a person stops drinking, while more severe complications can develop over the following days. Since withdrawal symptoms can progress quickly, anyone experiencing this condition during alcohol or benzodiazepine withdrawal should seek immediate medical care.
Delirium Tremens: A Medical Emergency
A serious complication of alcohol withdrawal is Delirium Tremens, or DTs. While DTs affect only a small percentage of people with alcohol withdrawal, they can be life-threatening without prompt treatment. Medical detoxification significantly reduces the risk of serious complications.
Stimulant-Induced Hallucinations
Methamphetamine and cocaine can also cause hallucinations, particularly after heavy or prolonged use.
These hallucinations may include:
- Hearing voices
- Feeling insects crawling on the skin
- Seeing people or shadows
- Extreme paranoia
Sleep deprivation, which commonly accompanies stimulant use, can further increase the risk. In many cases, hallucinations improve after the substance leaves the body, although some individuals may require additional medical or psychiatric treatment.
Other Causes
Addiction is not the only cause of this condition. Other possible causes include:
- Schizophrenia spectrum disorders
- Bipolar disorder during episodes of mania or depression with psychotic features
- Severe depression with psychotic features
- Dementia
- Parkinson’s disease
- Brain injuries
- High fever
- Infections affecting the brain
- Certain prescription medications
- Severe sleep deprivation
Treatment
Treatment depends on the underlying cause. For individuals with substance use disorders, treating the addiction itself is an essential part of preventing future instances.
Seek Your Recovery
Hallucinations happen when the brain misinterprets or generates sensory experiences without an external source. They can result from changes in brain chemistry caused by substance use, withdrawal, mental health conditions, neurological disorders, or medical illnesses. The experience can be frightening, but it is manageable. If you or a loved one is experiencing hallucinations, seek help. At Comprehensive Wellness Centers, we provide a complete approach to recovery and care.
