The Facts

A substance use problem is a medical condition. It is substance use that:

  • interferes with a person's relationships with family and friends,
  • interferes with a person's ability to fulfill work, school, or family obligations, or
  • results in legal problems and dangerous behaviour

It can also involve using or taking a substance in increasing amounts, going to great lengths to obtain the substance, experiencing withdrawal symptoms when the substance is stopped, or being unable to stop or reduce the use of the substance.

Depressants (e.g., alcohol, barbiturates, benzodiazepines), stimulants (e.g., amphetamines, cocaine, MDMA, or ecstasy), hallucinogenics (e.g., LSD), and opioids (e.g., codeine, heroin, and morphine) are the most commonly abused substances. Anabolic steroids are sometimes abused in order to improve athletic performance.

Substance use problems are very complex medical problems. Because they affect the brain, they are not just about willpower. Since there is a lot of stigma (shameful feelings) associated with substance abuse problems, health care professionals are not using terms such as "addiction," "addict," and "drug abuse" as much. Instead, they are using "substance use problems" and "people with substance use problems."


Almost all substances associated with substance use problems affect the "reward mechanism" in the brain. The main chemical messenger involved in the brain's reward mechanism is dopamine. Each time the person uses the substance they feel good, which makes them want to use the substance again. Over time, changes in the brain occur (e.g., less dopamine is produced), which lessens the pleasurable effects of the substance and larger amounts are needed to get the same feeling.

The causes of substance use problems aren't clear, although there are many factors that are thought to play a role. Heredity (genetics) appears to be involved, as the risk of substance use problems is higher for people with family members with these problems. A person's environment, such as school, work, friends, family, and cultural and religious beliefs, can also affect substance use problems.

Other mental health conditions such as anxiety and depression may also play a role. Substance use may also start when people try to manage unpleasant feelings and emotions (e.g., anger, stress, sadness). People who are subject to discrimination may also be at risk for substance use problems.

Symptoms and Complications

With substance use problems, people become dependent on the substance physically, psychologically, or both.

Physical dependence involves becoming tolerant to a substance. This means that more of the drug or substance is needed to obtain the same effect. When people stop taking the substance, they suffer withdrawal symptoms that can include shaking, headaches, and diarrhea. Drug withdrawal can even be life-threatening. Mental or psychological problems such as depression and anxiety can also occur during drug withdrawal.

Some people can be physically dependent on a substance without being psychologically dependent on it, especially when a medication is being used for a valid medical condition.

Psychological dependence involves feeling that a substance is needed to feel good and function. With psychological dependence, people often crave the substance and will go to great lengths to acquire the substance to fulfill their craving. Substances that cause psychological dependence usually act on the brain and have one or more of the following effects:

  • changes in mood (e.g., feeling "high")
  • reduced anxiety
  • feelings of superior abilities
  • effects on the senses (sight, hearing, etc.)

There are many complications to substance use problems. They can cause physical problems such as liver disease, lung disease, heart disease, vitamin deficiencies, and brain damage. Some substances can cause birth defects and others can damage the immune system, increasing the risk of infections.

People using amphetamines can suffer from heart attacks, strokes, severe anxiety, and paranoia. Hallucinogens, because they distort reality, can make people temporarily psychotic or make them try things they can't realistically do, like flying. Conditions such as AIDS or hepatitis transmitted through shared, dirty needles are another possible complication. Overdoses of certain substances can even lead to death.

Other complications of substance use problems include social consequences such as damage to work, family, and personal relationships. Those who neglect their families create social problems for their spouses and children. They may commit criminal acts such as stealing to support their substance use problem. If they drive while under the influence of substances, death or injury to themselves or others can result. Some substances can alter the perception of reality and make people apathetic about work or school. If a woman with a substance use problem is pregnant, she may make her fetus physically dependent on the substance she's using.

Making the Diagnosis

Urine and blood tests can show evidence of substance use but cannot distinguish if there is a problem or not.

The following may indicate that there is a substance use problem:

  • not being able to stop using the substance or cut down on the amount being used
  • feeling angry or defensive when someone comments about substance use
  • feeling guilty about substance use
  • using substances first thing in the morning

If you think you or someone you know might have a substance use problem, contact your doctor or your local support group or community centre for further advice. They will probably refer you to a trained counsellor who will assess your situation and help you determine if treatment is needed.

Treatment and Prevention

Substance use problems are treatable. Treatment may take a few weeks or months and may involve relapses, but for many, treatment is successful in the long term.

There are various treatment options available. A treatment plan will depend on a person's needs and will take into consideration such things as the severity of the problem, the person's support network, and the person's desire or motivation to enter treatment. The treatment plan may need to be altered as the needs of the person change. Treatment may include support groups, withdrawal or detoxification, counselling, or harm reduction for those who may not be ready to completely quit using substances that are causing problems.

Medications may also be used as part of a treatment plan. People with alcohol use problems can be given naltrexone*, a medication that helps to reduce cravings for alcohol; or acamprosate, a medication used to rebalance certain brain chemicals in people with substance use problems.

In some cases, other medications are used to treat withdrawal symptoms. During withdrawal of some substances, the person is gradually weaned off the substance by being given smaller and smaller doses. They may also be given less harmful substances instead of the ones they're dependent on. For example, people dependent on heroin are often given methadone. Methadone isn't as harmful to the brain as heroin or other narcotics.

Treatment plans almost always involve counselling. Counselling helps the person understand their substance use problem and helps them develop effective coping skills.

There are many types of treatment services, and availability may vary depending on where a person lives. Some programs are based in the community, and the person lives at home and comes to a treatment centre on a daily or regular basis. Other programs involve staying at a treatment facility for a certain period of time. The types of services and treatment approaches can vary between programs and centres, and a person with a substance use problem should be comfortable with the approach a program or centre uses.

During recovery, many people will have relapses along the way. These relapses should be viewed as temporary setbacks that can be a source of learning (e.g., what triggered the relapse and how to develop strategies that might help deal with this trigger in the future). Overcoming each relapse will bring the person closer to recovery. Recovery can be a long process for some people, but it is possible.

Many prevention programs (e.g., for schools, families, and the media) have proven to help prevent substance use problems. Helping youths to understand the risks of substance use problems reduces substance use. Fostering and modelling open and respectful communication within families helps to reduce the risk of developing substance use problems. Talk to your family about alcohol and other drugs. If you are not sure how to talk about alcohol and drug use, contact your doctor or community health centre for information and resources.


