Depression can be a highly debilitating illness that is underappreciated by most non-sufferers. Cases of unipolar, or standard depression, typically last one half to one year without an external reason such as the death of a loved one.

Distinguishing standard clinical depression from the depressive stage of bipolar disorder can be very difficult. Bipolar disorder can last for many years as severe depression without manifesting any signs of mania. To complicate matters, there are a number of different forms of bipolar disorder, with some forms oscillating between manic and depressive phases. Other forms consist entirely of depressive phases that come and go.

The classical way to distinguish between unipolar depression and that caused by bipolar disorder is to look at sleeping and eating patterns. Typically, when people have typical clinical depression, they have trouble sleeping and lose their appetite. In contrast, the atypical depression seen with bipolar patients has them sleeping longer or eating more than usual.

Mild to moderate cases of unipolar depression can often be improved by a rigorous exercise regimen. Unfortunately, this does not appear to be the case for severe depression. Psychotherapy and anti-depressants are generally prescribed for such cases of depression. It may require the trial of several different types of drugs before one is found that works. While it may be hard to see from the depth of a depression, there is hope for successful treatment.

Bipolar disorder usually requires some sort of pharmaceutical therapy, generally a mood stabilizer such as lithium. Anti-depressants can be used judicially, but in low concentrations, since they can trigger mania. They must be used with extreme caution and close monitoring. Atypical anti-psychotics are often used successfully at lower doses than with schizophrenic patients. Doctors need to monitor patients closely when prescribing these drugs, since the side effects can include an onset of diabetes, along with substantial weight gain.