Substance Intoxication Delirium

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Substance intoxication delirium is the diagnostic name for alcohol or drug-induced delirium. The condition is caused by intoxication from a psychoactive substance.

Disturbances in focus and attention are normal when people are under the influence of alcohol or drugs, and even when they are overtired. However, loss of focus and attention is usually temporary.

Substance intoxication delirium is a more serious state that lasts for much longer than the transient symptoms most people experience when they are intoxicated. A person who is experiencing substance intoxication delirium can become completely unable to attend to the external environment.

Here's what you need to know about the symptoms of substance intoxication delirium and what to do if you or someone you know is experiencing it.

Symptoms of Delirium

Delirium is a change in someone's state of consciousness that significantly disrupts their attention, awareness, and ability to process information about the world around them.

Someone who is experiencing delirium becomes less able to direct and focus their attention, keep their attention focused on something over time, or shift their attention from one thing to another.

If you are talking to someone with delirium, you might notice that you need to repeat your questions. The person might continue to focus on giving an answer to the first question to ask even when you have asked another. When a person is delirious, it is easy for them to become distracted by something that has nothing to do with what they have been asked.

In severe cases of delirium, a person can become so disoriented that they might not know where they are—or even who they are.

Memory

In addition to the loss of attention and focus, a person may lose their memory. A person experiencing substance intoxication delirium might not be able to remember things properly, and in particular, they may lose their memory for events that have recently happened.

People experiencing delirium might also lose their sense of orientation. They may not know where they are, the time, or the date.

A person's learning, language, and perception (which can include hallucinations) can also be affected.

Causes

Before a healthcare provider makes a diagnosis of substance intoxication delirium, they will check to make sure that the delirium is not from a condition that affected the person before becoming intoxicated from alcohol or drugs.

There are different physical and mental causes of delirium. A condition might be present in a person's medical record, or it could be undiagnosed.

If a person was experiencing delirium before using substances, it's unlikely that the symptoms are being caused by substance use or withdrawal. If a person does not have a physical or mental health condition that is known to cause delirium and they are using or withdrawing from substances when symptoms occur, it is more likely that they are experiencing substance intoxication delirium.

Substances That Can Cause Delirium

There are many psychoactive substances that can cause substance intoxication delirium. Some of the substances that are known to cause delirium are:

  • Alcohol
  • Amphetamines
  • Anxiolytics
  • Cannabis
  • Cocaine
  • Hypnotics
  • Inhalants
  • Opioids
  • Other hallucinogens
  • Other stimulants
  • Other substance
  • Phencyclidines
  • Sedatives
  • Unknown substances

How Long Does Delirium Last?

Delirium usually develops over a short period—from a few hours to a few days after the substance is taken. Delirium's severity can change over time, but it's often worse at night when there is less happening in a person's environment that can help keep them oriented.

Substance withdrawal delirium occurs after a person has discontinued using a substance (when they are in withdrawal).

Delirium usually occurs soon after a substance has been consumed and starts to take effect. In some cases, delirium continues even after the drug has worn off—a separate diagnosis called substance withdrawal delirium.

Whether delirium starts during intoxication or withdrawal, it usually subsides within hours or days after a person stops using the substance. However, delirium can last for weeks during withdrawal.

Treatment

Someone who develops delirium after using or while withdrawing from alcohol or any other substance needs immediate medical attention. If you are with someone who has taken a substance and has symptoms of delirium, call 911 and tell the paramedics what the person has taken.

People with a substance use disorder and those who are in withdrawal from a substance need close medical monitoring, either in the hospital or a treatment center.

A Word From Verywell

Delirium from substance use can be serious. If someone is using alcohol or any other substance and they develop symptoms of delirium—such as being unable to answers questions, being disoriented, or having trouble remembering things—they need immediate medical care.

People who are using substances or withdrawing from substances often need to be closely monitored by a healthcare professional to ensure their safety. Medical care is also important because in some cases, delirium is caused by a condition that is not related to substance use. Only a medical professional can make a diagnosis and recommended the appropriate treatment.

Substance Use/Addiction:

If you or a loved one are struggling with substance use or addiction, contact the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357 for information on support and treatment facilities in your area. 

For more mental health resources, see our National Helpline Database.

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Article Sources
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