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Substance-/Medication-Induced Psychotic Disorders


Carol Tamminga

, MD, UT Southwestern Medical Dallas

Last full review/revision May 2020| Content last modified May 2020

Substance- or medication-induced psychotic disorder is characterized by hallucinations and/or delusions due to the direct effects of a substance or withdrawal from a substance in the absence of delirium Delirium Delirium is a sudden, fluctuating, and usually reversible disturbance of mental function. It is characterized by an inability to pay attention, disorientation, an inability to think clearly... read more .

Episodes of substance-induced psychosis are common in emergency departments and crisis centers. Many substances may bring on these episodes, including alcohol Alcohol Alcohol (ethanol) is a depressant. Consuming large amounts rapidly or regularly can cause health problems, including organ damage, coma, and death. Genetics and personal characteristics may... read more , amphetamines Amphetamines Amphetamines are stimulant drugs that are used to treat certain medical conditions, but are also subject to abuse. Amphetamines increase alertness, enhance physical performance, and produce... read more , cannabis Marijuana Marijuana (cannabis) is a drug made from the plants Cannabis sativa and Cannabis indica that contain a psychoactive chemical called delta-9-tetrahydrocannabinol (THC). Marijuana produces a dreamy... read more , cocaine Cocaine Cocaine is an addictive stimulant drug made from leaves of the coca plant. Cocaine is a strong stimulant that increases alertness, causes euphoria, and makes people feel powerful. High doses... read more , hallucinogens Hallucinogens Hallucinogens are a class of drugs that cause profound distortions in people's perceptions. Hallucinogens distort and intensify sensations, but the actual effects are variable and highly unpredictable... read more , opioids Opioids Opioids are a class of drugs derived from the opium poppy (including synthetic variations) that are pain relievers with a high potential for misuse. Opioids are used to relieve pain, but they... read more , phencyclidine Ketamine and Phencyclidine (PCP) Ketamine and phencyclidine are chemically similar drugs used for anesthesia but are sometimes used recreationally. Ketamine is available in powder and liquid form. The powder can be snorted... read more (PCP), and sedatives Antianxiety and Sedative Drugs Antianxiety and sedative drugs are prescription drugs used to relieve anxiety and/or help with sleep, but their use can result in dependency and a substance use disorder. Using prescription... read more . To be considered substance-induced psychosis, the hallucinations and delusions should be greater than those that typically accompany simple substance intoxication or withdrawal, although the person may also be intoxicated or withdrawing. 

Symptoms are often brief and disappear once the drug that is causing the symptoms is cleared from the body, but psychosis triggered by amphetamines, cocaine, or PCP may last for many weeks.


  • A calm environment

  • Often a benzodiazepine or antipsychotic drug

In most substance-induced psychoses, stopping the substance and taking an antianxiety or antipsychotic drug is effective.

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