Several mental illnesses occur due to substance abuse – referred to as substance-induced mental disorders. These include delirium, psychosis, persisting amnesia disorder, sexual dysfunction, sleep and anxiety disorders, and more.

It is crucial to distinguish substance-induced disorders from independent co-occurring mental health conditions because the specific group of symptoms that occurs at a particular period of time is an apparent trait of substance abuse rather than an underlying mental disorder.

Here is a list of the most common mental disorders caused by addictions and what you should know about them:


Psychosis is a mental disorder characterized by delusions, hallucinations, thought disorders, and paranoia. In most cases, psychosis is triggered due to severe drug abuse.

Hallucinations can occur during acute intoxication or withdrawal stages when people abuse certain drugs, such as LSD, PCP, cocaine, amphetamines, cannabis, ketamine, heroin, and MDMA.

Hallucinations are often auditory such as hearing voices or seeing things that are not real. Some individuals may also have tactile hallucinations, which involve feeling sensations on parts of their body that are not real. Delusions are false beliefs and thoughts that don’t change despite evidence to the contrary.

Psychosis caused by substance abuse tends to go away once the person stops using the drug they abused. For example, non-addictive medications are often used during cocaine addiction treatment to normalize the neurotransmitter levels and overall brain chemistry. However, psychotic disorders can persist even after a person stops using the drug that triggered it. This is known as substance-induced psychosis, which is also referred to as substance-induced psychotic disorder.

Persisting Dementia

Dementia is a condition that causes memory loss and difficulties in thinking, problem-solving, speaking, and understanding. It affects thinking and behaviour skills to such an extent that it becomes difficult for people to function at home, work, or social settings.

Alcohol abuse is the leading cause of dementia and causes delirium tremens (DTs) in people withdrawing from alcohol. DTs are considered a form of dementia with confusion, hallucinations, and seizures.

It is important to note that dementia can also be caused by traumatic brain injuries, Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease. However, these diseases don’t develop due to substance abuse.

Delirium Tremens (DTs)

Delirium tremens occurs in people who are withdrawing from alcohol, sedative or other substance abuse. The symptoms of delirium tremens include confusion, agitation, fever, hallucinations, sweating, dehydration, seizures, and tremors.

Delirium tremens usually occurs about 48 hours after a person with a sedative addiction has stopped using the drug. The length of time taken for delirium tremens to occur depends on how long the person was taking sedatives and what kind of sedatives were abused. For example, withdrawal symptoms from benzodiazepines usually occur within 15 hours of their last use, whereas withdrawal symptoms from alcohol typically occur after about 24 hours.

Sleep Disorders

Some examples of sleep disorders caused by alcohol abuse include insomnia and hypersomnia. Insomnia refers to difficulty falling asleep, while hypersomnia refers to difficulty waking up. Both conditions can lead to daytime fatigue, impairing work performance and increasing the risk of accidents due to feeling sleepy at work or while driving.

Insomnia can also lead to mood changes such as irritation and depression. People with hypersomnia may also suffer from depression because they feel tired all the time. Insomnia and hypersomnia can occur simultaneously in people with alcohol dependence syndrome.

Obsessive-Compulsive Disorder (OCD)

Obsessive-compulsive disorder (OCD) is a mental health condition characterized by a set of unwanted thoughts that causes anxiety in individuals suffering from it. 

Obsessions are recurrent and persistent disturbing thoughts in nature, such as fears of being contaminated by germs or negative thinking about someone else or themselves. 

Compulsions are repetitive behaviours such as excessive washing or checking behaviours that people feel they must do to relieve their anxiety or obsessions. Individuals with OCD often engage in compulsive behaviours that seem irrational or senseless. Still, they feel compelled to do them anyway due to the extreme anxiety level if they don’t do them.

OCD can also be caused by substance abuse because drugs such as alcohol and opioids alter the chemical composition of neurotransmitters in the brain, which control cognitive functions related to emotions such as impulsiveness and fearfulness. 

Obsessive-compulsive disorder (OCD) is one of the most common mental disorders caused by substance abuse. It is often associated with substance-induced anxiety or panic attacks. The most common drugs that trigger OCD are alcohol, cocaine, amphetamines, cannabis, and opioids.

Sexual Dysfunction

Substance-induced sexual dysfunction refers to a sexual disorder that occurs in people who are abusing drugs or alcohol. Alcohol abuse is one of the leading causes of erectile dysfunction in men. Women who abuse drugs such as opioids may suffer from decreased libido and an inability to reach orgasm during sex.

Amphetamine abuse may cause delayed ejaculation, while cocaine has been known to cause erectile dysfunction in both men and women. Methamphetamine abuse is also associated with low libido in both men and women.

Generalized Anxiety Disorder (GAD)

According to the Anxiety and Depression Association of America, generalized anxiety disorder (GAD) is a mental health condition characterized by “persistent and excessive worry about a number of different things. People with GAD may anticipate disaster and may be overly concerned about money, health, family, work, or other issues.” 

GAD can be caused by substance abuse because many abuse substances such as alcohol, heroin, cannabis, and opioids are considered central nervous system depressants that act on the same brain chemistry as GAD medications. The differences between these drugs and GAD medications are their potency and effectiveness, making it easier for people to become dependent on substances than GAD medications.


Negative impacts of substance abuse on our bodies and mental health are apparent. However, it is crucial to understand that some addictions can lead to severe mental health disorders that frequently occur during alcohol or drug intoxication or withdrawal and may remain persistent.

These are called substance-induced mental disorders and include psychosis, sleep disorders, dementia, obsessive-compulsive disorder, etc. Being mindful of such harsh consequences allows you to prevent addiction from developing and avoid irreparable damage to your health.