How is depression diagnosed?

Your doctor can't diagnose depression through a lab test or X-ray. Instead, doctors must make a diagnosis by asking questions about your feelings and behaviour. That said, your doctor may still do a physical exam or order blood work to rule out other causes for your symptoms.

You play an important role in helping your doctor make an accurate diagnosis. Since your depression symptoms are unique to you, it is crucial that you explain any changes in your emotions, the way you think, as well as any physical symptoms that you've experienced.

If you are having difficulty thinking or if you experience unexplained aches and pains, mention these to your doctor so they can make the right diagnosis and choose the best treatment for your symptoms.

A person is diagnosed as having major depressive disorder (MDD) when they have one or more major depressive episodes (a case of serious depression). In a major depressive episode, symptoms persist most of the day, nearly every day for at least two consecutive weeks. These symptoms must be new or noticeably worse than they were previously. The doctor usually looks for at least 5 of the following symptoms, one of which must be either depressed mood or loss of interest and enjoyment:

• depressed mood most of the day, almost every day
• loss of interest and enjoyment in all or most activities most of the day, nearly every day
• increase or decrease in appetite, or significant weight loss (when not dieting) or weight gain
• problems sleeping
• agitation or restlessness , noticeable by others around you (e.g., friends, family)
• lethargy or feeling slowed down, noticeable by others around you (e.g., friends, family)
• fatigue or loss of energy
• excessive or inappropriate feelings of guilt or feelings of worthlessness
• difficulty thinking or concentrating, or trouble making decisions
• recurrent thoughts of death or suicide

For information on the different symptoms of depression, see our Symptom Checker. For help talking to your doctor, see our Doctor Discussion Guide.

For more information on depression and its management, visit www.depressionhurts.ca.