Substance-Induced Disorders

Substance-induced disorders are a type of substance-related disorder that involves problems caused by the direct effects of a substance.

Substance-induced disorders include (discussed below):

• Intoxication;
• Withdrawal; and
• Substance-induced mental disorders.

Many different substances can cause a substance-induced disorder.

A disorder can occur regardless of whether or not the substance:

• Is legal;
• Is socially acceptable; or
• Has an accepted medical use (with or without a prescription).

The specific manifestations and treatment of intoxication and withdrawal vary by the substance and are discussed elsewhere in the website.

Individuals who inject drugs also can develop problems related to the injection itself rather than the drug, particularly infections.

Intoxication

Intoxication refers to the immediate and temporary effects of a specific drug. Intoxication impairs the individual’s mental function and judgement and may alter mood.

Depending on the drug, the individual may feel a sense of excitement or an exaggerated feeling of well-being (or euphoria), or the individual may feel calmer, more relaxed, and sleepier than usual.

Many drugs impair physical functioning and coordination, leading to falls and vehicle crashes.

Some drugs trigger aggressive behaviour, leading to fighting.

As larger amounts of the drug are used (called an overdose), adverse effects become more obvious, with serious complications and sometimes risk of death.

Tolerance means that individuals need more and more of the drug to feel the effects originally produced by a smaller amount.

Individuals can develop tremendous tolerance to drugs such as opioids and alcohol.

Withdrawal

Withdrawal refers to symptoms that develop when individuals stop taking a substance or take significantly less than usual.

Withdrawal causes various unpleasant symptoms that differ depending on the substance involved.

Withdrawal from some drugs (such as alcohol or barbiturates) can be serious and even life threatening.

Most individuals who experience withdrawal know that taking more of the substance will reduce their symptoms.

Whether withdrawal occurs depends only on the substance and how long it is used, not whether the:

• Individual has a substance use disorder;
• Is using the substance recreationally; or
• Substance is illegal.

Some prescription drugs, particularly opioids, sedatives, and stimulants, can result in withdrawal symptoms even when taken as prescribed for legitimate medical reasons and for relatively brief periods (less than 1 week for opioids).

Individuals who have withdrawal symptoms were previously termed physically dependent upon the substance.

However, “dependence” has negative connotations suggesting illicit drug use, so medical professional s prefer to avoid this terminology.

Substance-Induced Mental Disorders

Substance-induced mental disorders are mental changes produced by substance use or withdrawal that resemble independent mental disorders such as depression, psychosis, or anxiety.

For a mental disorder to be considered substance induced, the substance involved must be known to be capable of causing the disorder. Substances can be members of the 10 classes of drug that typically cause substance-related disorders:

• Alcohol.
• Antianxiety and sedative drugs.
• Caffeine.
• Cannabis (including marijuana and synthetic cannabinoids).
• Hallucinogens (including LSD, phencyclidine, and psilocybin).
• Inhalants (such as paint thinner and certain glues).
• Opioids (including fentanyl, morphine, and oxycodone).
• Stimulants (including amphetamines and cocaine).
• Tobacco.
• Other (including anabolic steroids and other commonly abused substances).

But many other substances can cause mental disorders.

Common examples include anticholinergic drugs and corticosteroids, which may cause temporary symptoms of psychosis.

In addition, the mental disorder should:

• Appear within 1 month of intoxication with or withdrawal from the substance.
• Cause significant distress or impair functioning.
• Not have been present before use of the substance.
• Not occur only during acute delirium caused by the substance.
• Not last for a substantial period of time.
  • Certain disorders of thinking caused by alcohol, inhalants, or sedatives/hypnotics, and perceptual disorders caused by hallucinogens may be long lasting.