f you or someone you know is showing symptoms of SAD, talk to a health care provider or a mental health specialist about your concerns. They may have you fill out a questionnaire to determine if your symptoms meet the criteria for SAD.

To be diagnosed with SAD, a person must meet the following criteria:

They have the symptoms of depression or the more specific symptoms of winter- or summer-pattern SAD listed above.

Their depressive episodes occur during specific seasons (winter or summer) for at least 2 consecutive years. However, not all people with SAD experience symptoms every year.

Their depressive episodes during the specific season are more frequent than depressive episodes experienced at other times of the year.