Dysthymia (or persistent depressive disorder) is one of many forms of Depression. It is not to be confused with the more common Major Depression, in which one experiences chronic episodes of Depression for a few days. Dysthymia is a functioning form of Depression in which the person does not feel majorly depressed every now and then, but rather experiences depression in a low level form almost every day for months or years at a time. People who suffer from Dysthymia usually go about their daily routine as normal. Their peers may not even know they have Depression. In addition to low level Depression, they may also experience major depressive episodes. Dysthymia, unlike other forms of Depression, can be more commonly linked to trauma suffered earlier in life. It is usually linked to Post Traumatic Stress Disorder and with talk therapy can sometimes be dismantled. However, Dysthymia can also be passed down from relatives or caused by chemical changes in the brain.
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