WebMD explains atypical depression -- a type of depression that can be difficult to treat. With this depression, you may brighten in response to positive events, eat and sleep too much, feel heaviness in your arms or legs, and feel. Do you feel depressed or suicidal? Do you have a question related to your own or someone else's mental health? We are here to help call our free hotline and. Atypical feature as a specifier can be applied to major depressive episodes, bipolar disorder when a major depressive episode is the most recent mood episode,. Instead, the condition is now called major depression with atypical features. She does not improve when given the tricyclic antidepressant imipramine, but most of her symptoms go away in a few weeks when she is switched to phenelzine,.