Symptoms can last anywhere between a few weeks to years. To be diagnosed with depression, you must exhibit several symptoms daily for two weeks. How long the condition will last after the lapse of the two weeks differ from one person to another. And the time frame your state will last will depend on several factors, such as the type of depression disorder you have. How severe your condition is, and much more! However, the depressive episode timeframe can range between six to eight months. For some people, symptoms may come and disappear on their own at times. For others, symptoms can persist over the years.