Duloxetine for Chronic Depression: a Double-blind Study

The investigators are studying a new antidepressant medicine, duloxetine, for the treatment of people with chronic depression. Duloxetine (trade name Cymbalta) was recently approved by the FDA for the treatment of major depression. The investigators are testing whether this medicine is also effective for adults with chronic depression (dysthymic disorder or dysthymia). Chronic depression, lasting two or more years, often causes significant suffering and impairment. The investigators study involves a 6 to 10 week double-blind Initial Phase during which half of the participants will take the new medication and half will take a placebo (an inactive look-alike pill). After the Initial Phase, a 12-week Continuation Phase will begin, during which all subjects can be treated with an FDA-approved antidepressant medication. Eligible subjects may also receive MRI scans, to help the investigators understand how antidepressants work in treating depression.