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Alcohol & Other Drugs

Learn About Co-existing Problems


Author: Canadian Institute for Substance Use Research


What is a co-existing problem?

A co-existing problem occurs when we have a mental health problem and, at the same time, use substances in ways that could result in significant harm. It is not known how many people experience this dual problem (sometimes called a 'concurrent disorder'). But a national study in the United States, looking at mental illness alongside substance use in a lifetime, suggests about half of the people experiencing a mental illness also struggle with a substance use problem, and vice versa.

What are some of the risk factors?

The factors that influence the risk of developing a dual mental health and substance use problem range from personal characteristics to broad social factors. These include family history, past or ongoing trauma, poverty or unstable income, family values and community cultures.

These and other factors interact in different ways in each of us. They influence our behaviour and the impact that behaviour might have on our health. For example, if I experience trauma, I cannot change the occurrence, but I can choose to engage in behaviours that may increase or decrease my risk of developing problems later on.

Often our choices are influenced by health behaviours observed at home or in our communities. For example, a child whose parent uses alcohol as a coping strategy for dealing with a mental health challenge may be influenced to follow the same pattern or to adopt a different pattern. Other influences are likely to affect the choice.

How might a co-existing problem develop?

One way we may develop a co-existing problem relates to the reasons we use alcohol or other drugs. For instance, a person with a mental health issuesuch as anxiety might begin using a prescription medication to help them cope with their experiences but may develop drug-related problems after prolonged use. Or a person experiencing depression may try to feel better by drinking alcohol but later find they are drinking too much too often.

It works the other way too. Substance use can aggravate, or may lead to, a mental health issue. Broken relationships, money issues and other consequences associated with harmful drinking may lead to depression or anxiety. Likewise, drinking alcohol above low-risk limits can worsen a mild case of depression or anxiety.

In short, our mental health can both affect and be affected by our substance use.

What challenges might someone face?

A person experiencing a substance use and mental health problem may face barriers to adequate treatment and other needs. There are various reasons why this might happen.

Our health and social care systems are not well equipped to address intertwined problems. Programs are often arranged within separate systems, each focused on a different need, and healthcare providers may recognize and respond to only one part of a person’s needs. As a result, aperson may end up receiving care only for a mental health issue or only for a substance use issue instead of both. And people with needs such as supported housing may face additional barriers, for example, a requirement to stop using drugs when seeking assistance.

Talking openly about mental health and substance use problems is not always comfortable. Some people, for instance, may be worried about being thought of badly by others, and fail to disclose information about their mental health and substance use to their healthcare provider. Others may be uncomfortable asking about their concerns (e.g., whether or not there may be a link between a mental health problem and substance use). Still others may identify more strongly with one problem over the other and therefore talk more candidly about it, resulting in their receiving help for only their substance issue or only their mental health concern.

What to do if you or someone you know is experiencing a co-existing problem

If you know someone who is experiencing a co-existing problem, or if you are concerned about yourself, don’t be afraid to reach out. One way is to talk to a healthcare professional you feel comfortable confiding in. An assessment of your symptoms may be helpful. In addition to talking to a healthcare professional, consult the resources below for more information.

information on substance use treatment options and resources throughout BC, call the Alcohol and Drug Information and Referral Service at 1-800-663-1441. In Greater Vancouver, call 604-660-9382. They can refer you to programs and services across the province.

For support, information and resources specific to mental health in BC, call your local Crisis Line. Crisis lines aren’t only for people in crisis. You can call for information on local services or if you just need someone to talk to. If you are in distress, call 310-6789 (do not add 604, 778 or 250 before the number) 24 hours a day to connect to a BC crisis line without a wait or busy signal.

To better understand how substances play a role in your life, visit the You and Substance Use Workbook on the Here to Help website: This website also features detailed information on substance use and mental health, including the Depression, Anxiety, Alcohol and Other Drugs information sheet.

You can also find information about a wide variety of substance use issues on the Canadian Institute for Substance Use Research website:

About the author

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The Canadian Institute for Substance Use Research, formerly CARBC, is a member of the BC Partners for Mental Health and Substance Use Information. The institute is dedicated to the study of substance use in support of community-wide efforts aimed at providing all people with access to healthier lives, whether using substances or not. For more, visit


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