Medication or Substance-Induced Neurocognitive Disorder

When Alcohol, Drugs or Medications Cause Mild Problems With Brain Functioning

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Mild neurocognitive disorder due to substance/medication use and major neurocognitive disorder due to substance/medication use are the diagnostic names for two alcohol- or drug-induced major neurocognitive disorders―"major" obviously being the more severe form.

Unlike the problems with mental functioning that happen during intoxication or with a hangover the morning after alcohol use—that pass fairly quickly—mild neurocognitive disorder continues to cause difficulty with mental functioning on an ongoing basis. For some people, it can impact their day-to-day functioning permanently.

Many people who develop a neurocognitive disorder after using alcohol, drugs, or medications, don't actually realize they have these problems.

Family and friends may be the first to notice problems with paying attention, remembering important things they need to do, and planning properly to manage their lives. In fact, the problems that people with mild neurocognitive disorder due to substance or medication use experience may only be helped by family or friends providing or arranging for additional support for the person in their daily lives.

What Are Cognitive Deficits?

Cognitive deficits are problems with mental functioning. Mental functioning ranges from perception to memory, from managing emotions to planning for the future, or even simply planning your meals and activities for today.

Mental functioning is also needed for controlling your body movements, balance, coordination, as well as speech, communication of all kinds, understanding and getting along with other people. Even recognizing people and knowing the role they play in your life is controlled by mental functioning.

So when cognitive deficits develop, a person can quickly find life difficult to cope with, and problems can develop rapidly. A huge risk for people with a history of drinking or drug use is that they can go back to these unhealthy ways of coping with problems, making cognitive functioning even worse.

Cognitive deficits can occur as part of a brain disorder, but when they are due to a substance or medication use, there is a decline or worsening of mental abilities that were at a higher level of functioning. There is a variety of cognitive deficits that can occur as part of this condition, including:

  • Difficulty paying attention or concentrating on what you are doing or what is going on around you
  • Difficulty with "executive functioning"; skills like making plans for the future, controlling impulses to do things that might not be a good idea, particularly in the long term, and making decisions about everything from what to wear on a hot or cold day to financial planning for the next 10 years
  • Learning new skills—this doesn't just mean learning in school, or learning skills like driving, but learning everyday things we are all required to do, like learning to use a new type of technology
  • Problems with remembering information—not only difficult, abstract information, but everyday information, such as your phone number, address, and where you need to go today
  • Difficulties with speaking and communicating clearly with other people
  • Perceptual-motor skills—how you control your body and movements, even something you take for granted, such as walking
  • Social awareness and understanding of other people—from treating people with caring and courtesy through to knowing when someone is trying to rip you off

Is It a Substance-Induced or Pre-Existing Disorder?

When doctors or psychologists give a diagnosis of mild neurocognitive disorder due to substance/medication use, they check to make sure that the cognitive deficits weren't there before the person used the alcohol, drug, or medication that is thought to be responsible for their difficulties.

This is because there are different types of neurocognitive disorders, and if the symptoms were there before the substance use, the person is probably not suffering from the substance/medication-induced type of neurocognitive disorder, but instead, some other type of neurocognitive disorder.

For people who have a long history of substance use, it can be difficult to know what came first—the substance use or the neurocognitive disorder—but this can often be determined by taking a careful history of substance use and cognitive functioning, as well as carefully managing detox with an extended period of abstinence from all alcohol, drugs, and medications that may have induced the disorder.

How Soon After Taking the Drug Can Neurocognitive Problems Be Induced?

In some cases, neurocognitive problems can develop almost immediately after taking the drug or medication. As the brain doesn't typically function at its best during drug intoxication and withdrawal, it can be difficult for doctors to know whether the mental problems the person is experiencing are the result of a slow recovery of normal brain functioning after using alcohol or drug use for a long time.

Usually, mental skills will improve a great deal within a few days of stopping drinking or taking drugs, and continue to improve as the person moves through the detox process over the next couple of weeks. Sometimes, it can take months or even years for functioning to return to normal. However, in other cases, even if the person improves, the problems can be persistent, and normal functioning may not fully return.

Finally, for the diagnosis of mild (rather than major) neurocognitive disorder due to substance/medication use to be given, the person would still be independent in everyday activities, such as paying bills or managing medications, but these activities may take more effort or compensatory strategies, or the person might need extra help to accomplish them.

Which Drugs Cause Substance-Induced Neurocognitive Disorder?

A wide variety of psychoactive substances can cause mild neurocognitive disorder due to substance/medication use, including the following:


We know more about mild neurocognitive disorder in alcohol users than in other drug users, because more research has been conducted on drinkers than on drug users, and the impact of alcohol on the health of the brain is well known.

About 30 to 40% of heavy drinkers have some form of alcohol-induced mild neurocognitive disorder during the first month or two after they stop drinking.

These problems are more likely to continue for a longer time in people who are 50 or older before they quit drinking.

Even though psychological tests show that their brains are not working normally, people with this condition may not be aware they are impaired, therefore family and friends may be the ones to notice the person is having difficulty.


People can sometimes suffer from mild neurocognitive disorder right after intoxication with inhalant drugs, and for some people—even after quitting inhalants—these problems can continue. A study of inhalant users showed that most had improved significantly after two years of discontinuing inhalant use, and most had returned to normal cognitive functioning after 15 years of abstinence.

The exception was a group of inhalant users who had developed 'lead encephalopathy' from leaded petroleum (gasoline) inhalation. These people continued to have inhalant-induced neurocognitive disorder even 15 years after stopping sniffing gasoline. In these cases, the disorder may not be mild but may be major, meaning that the person's ability to function independently is severely disrupted.


About a third of people who use cocaine experience mild neurocognitive disorder after they quit cocaine, with some people continuing to have these problems long term after they have quit. A study has shown that people who are active cocaine users perform significantly worse on various tests of neurocognitive functioning than people of the same age who do not use cocaine, regardless of their age.

However, the same study showed that older cocaine users perform much worse on tests of particular cognitive functions such as psychomotor speed, attention, and short-term memory than younger cocaine users.

While it is normal and natural for people's neurocognitive abilities to decline with age, this normal deterioration is more pronounced in older cocaine users.

Older cocaine users are particularly vulnerable to problems that come with age, such as being able to control their movements, focus their attention on what they are doing and what is going on around them, and remembering everything from what they need to do today, to the important people and events in their lives.


As with cocaine, about a third of people who use methamphetamine suffer from a mild neurocognitive disorder, with persistent problems in some users after abstinence. Neurocognitive problems can also result from cerebrovascular disease which leads to diffuse or focal brain injury. The executive functioning of methamphetamine users is even worse in people who have also used the drug ketamine.


About 33 to 39 percent of people who use opioids have neurocognitive problems, and some continue to have problems even after they have quit. Research has shown that opioid-dependent adults have high rates of neurocognitive impairment, with severe problems in learning and memory.

People who have been addicted to alcohol and cocaine at some point in their lives, as well as opioids, have a greater neurocognitive impairment, particularly in executive functioning. Because executive functioning is critical for making decisions, and because having problems with learning and memory can interfere with properly taking in information, people with opioid addictions may need more support for making medical decisions than most people.


About a third of phencyclidine users have intermediate neurocognitive problems after they stop, with persistent problems in some users after abstinence.

Sedative, Hypnotic, or Anxiolytic Medications

As with many types of drugs, there are intermediate problems in about a third of users of sedative, hypnotic, and anxiolytic medications, with persistent problems in some users after abstinence. The fact that most people who use these drugs are prescribed them presents particular problems, especially with issues such as driving impairment.

Experimental research has shown specific deficits in driving ability in people who use these medications. Benzodiazepines, a type of central nervous system depressant, is also associated with the greatest likelihood of causing accidents.

A Word From Verywell

Cognitive impairments resulting from alcohol, drug, or medication use can be confusing and upsetting and can cause problems for the individual affected and those around them. The good news is that if you stop drinking or using the drug or medication under medical supervision, the odds are good for making a full recovery, even if this takes time.

If you or someone you care about is affected, getting a diagnosis will help determine what help is needed for functioning well in everyday life.

Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  • Cairney S, O' Connor N, Currie B, et al. A Prospective Study of Neurocognitive Changes 15 Years After Chronic Inhalant Abuse. Addiction,108(6):1107-1114. 2013.

  • Chen Y, Wang L, Lin S, Chen C. Neurocognitive Profiles of Methamphetamine Users: Comparison of Those With or Without Concomitant Ketamine Use. Substance Use & Misuse ,50(14):1778-1785. 2015.

  • Stone B, Correa K, Berka C, et al. Behavioral and Neurophysiological Signatures of Benzodiazepine-Related Driving Impairments. Frontiers In Psychology, 2015.

  • Walvoort S, van der Heijden P, Wester A, Kessels R, Egger J. Self-Awareness of Cognitive Dysfunction: Self-Reported Complaints and Cognitive Performance in Patients with Alcohol-Induced Mild or Major Neurocognitive Disorder. Psychiatry Research, 245:291-296. 2016.

By Elizabeth Hartney, BSc, MSc, MA, PhD
Elizabeth Hartney, BSc, MSc, MA, PhD is a psychologist, professor, and Director of the Centre for Health Leadership and Research at Royal Roads University, Canada.