Antidepressant drugs

Antidepressant drugs (often called "antidepressants") are widely used in Canada to treat depression and other mental health issues. It is important to take them as directed. Side effects are usually manageable, but stopping treatment suddenly can cause problems.


Depression is a type of mood disorder and is a common reason for visiting a doctor in Canada. Though many people feel sad, discouraged or "down" for a short time when things don't go well, in people with depression, these feelings last longer than expected and may happen without obvious life stress.

Symptoms of depression can include:

  • persistent sadness
  • loss of interest in things and people you once enjoyed
  • feeling tired all the time, or as if you have no energy
  • crying for no apparent reason
  • feelings of despair, hopelessness or worthlessness
  • trouble concentrating, making decisions or remembering
  • thoughts of suicide or death
  • changes in appetite or sleep patterns
  • feelings of guilt

If not treated, depression can affect an individual's quality of life and relationships. It can also cause him or her to lose time from work or school.

Depression is treatable, and those affected can get better. The most common treatments are antidepressant drugs, psychotherapy, or both. With proper treatment, most people with depression see their symptoms improve and can get back to living normal and productive lives.

How antidepressants are thought to work

Chemicals like serotonin, norepinephrine and dopamine are naturally present in our bodies. They are needed for normal brain function. In people with depression, it is thought that there may be an imbalance of these chemicals (called neurotransmitters) in the brain. Antidepressants are believed to work by bringing one or more of these chemicals back into balance.

There are many types of antidepressants on the market. Talk to your health care provider to see if taking antidepressants is the best choice for you, and if so, which one you should take.

Many people see an improvement with the first antidepressant they use. But you may need to try another type, a higher dose or a combination of drugs to find what works best for you. Also, it may take up to a month to notice the full benefit of the drug.

Even once you start to feel better, keep taking the antidepressant as directed by your health care provider. Most people take antidepressants for at least 6 to 12 months, and some for longer. Make sure you talk to your health care provider before you stop using yours.

Side effects of antidepressants

All drugs, including antidepressants, have some risk of side effects, even if you use them as directed. For most people, these side effects are usually temporary and manageable. But some may be serious.

If you have a side effect that bothers you, or you experience something unusual, talk to your health care provider about what to do. You can also report side effects to Health Canada toll-free at 1-866-234-2345 or online at MedEffect.

Family members should closely watch patients for any new or worsened mood or behaviour problems, such as unexpected hostility, agitation or anxiety. This is especially important in the first few weeks after a patient starts an antidepressant.

As a patient, it is also very important to follow up regularly with your health care provider and keep talking about how you are feeling.

More information on the potential side effects of a drug is available in its official Canadian "product monograph," which contains important prescribing and safety information for health professionals and patients. Product monographs are available by searching Health Canada's Drug Product Database.

How to stop antidepressant treatment

Do not stop using an antidepressant or reduce your dose on your own. Your doctor or health care provider will work with you when the time is right to stop taking your antidepressant.

When you stop taking an antidepressant, you may have discontinuation (withdrawal) symptoms, or your depression may come back. Discontinuation symptoms may include:

  • dizziness or vertigo
  • tingling or electric shock sensations
  • unsteady gait (trouble walking normally)
  • nausea
  • flu-like symptoms
  • anxiety or agitation
  • crying spells
  • irritability

These symptoms do not mean you are addicted to the antidepressant. Antidepressants are not considered addictive and do not lead to drug abuse (that is, they do not lead to compulsive use to get "high"). But because your body has gotten used to them, suddenly stopping can cause unwanted side effects. In rare cases, it can be difficult to stop taking an antidepressant even with gradual tapering of use.

Instead of stopping antidepressants all at once, it is important to work with your health care provider to decrease your dose a little at a time, when the time is right.

Reduce your risk

These steps will help you reduce your risk of problems when taking antidepressants:

Talk to your doctor

  • Before using antidepressants or any other medications, talk to your health care provider. Ask about the benefits and risks, including possible side effects. Ask about other treatment options, like counselling.
  • Describe all your symptoms to your health care provider. Say which ones bother you the most.
  • Let your health care provider know about any personal or family history of mental illness. Tell them about other medical conditions and allergies. Let them know if you are pregnant or breastfeeding.
  • Antidepressants can interact with other medicines. Tell your doctor and pharmacist about all other health products you are taking, including prescription and over-the-counter drugs, vitamins and natural health products. Do not start taking new medicines without first checking with your health care provider.

Use your medicine safely

  • Read the label and take antidepressant medicine exactly as directed. Do not skip doses. Find out from your doctor or pharmacist what to do if you miss a dose.
  • Do not suddenly stop taking antidepressants. Talk to your health care provider, who will come up with a plan to reduce your dose slowly when the time is right.
  • Report side effects (adverse reactions) to your health care provider, and to Health Canada's MedEffect website.
  • Store antidepressants and all other drugs in a safe (ideally locked) place, out of the reach of children and teenagers.
  • Never share your prescription with anyone else.
  • Drugs should never be thrown out at home (in the sink, toilet or trash). Bring any unused medication back to the pharmacy for safe disposal.

Health Canada strongly advises against taking any prescription drug that has not been prescribed for you by your health care professional.

The Government of Canada's role

Health Canada regulates drugs like antidepressants under the Food and Drugs Act. We review scientific information about the safety and efficacy of drugs before they are allowed to be sold in Canada.

Health Canada also monitors the safety of health products after they have been approved for sale in Canada. Manufacturers must provide Health Canada with reports of serious side effects for the health products they sell in Canada and maintain the most up-to-date information on their health products. Important drug safety information is available in its official Canadian product monograph, available by search of Health Canada's Drug Product Database.

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