Depression is a complex disorder, and there's no simple test doctors can do to see whether or not you have it. However, there are many tools a therapist may use to check for depression, including having you fill out a questionnaire. Certain experiences can also cause or put you at risk for depression and sharing this information with a doctor or therapist may help them to make a diagnosis. Some potential causes and risk factors for depression may include:   Trauma and grief. Abuse or other violent experiences can cause depression, whether they occurred recently or otherwise. Grief after the death of a friend or other traumatic event can develop into full-blown depression.  Stressful events. Sudden changes, even positive ones such as getting married or starting a new job, could be responsible. More long term stress from caring for a sick person or going through a messy divorce are common triggers as well.  Health conditions. Chronic pain, thyroid disease, and many other medical conditions can bring on depression, especially if you are fighting a long battle with an illness.  Medication and substances. Read the side effects label on any medication you are taking. Avoid alcohol and other drugs to see if your symptoms improve; depressed people often abuse drugs, which makes the problem worse.  Relationship problems. If you are struggling in one or more of your personal relationships, then this may also put you at risk of depression.  Family history of depression. If a relative of yours has struggled with depression, then you are at a higher risk of developing it yourself.  Loneliness, isolation, or a lack of social support. If you do not have a support system and spend a lot of time on your own, then this can also put you at risk of depression.  Financial strain. If you have been struggling with debt or simply trying to keep up with your monthly expenses, then this can put you at risk of depression. If you recently gave birth, consider when the depression began. New mothers often experience mood swings,...

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