Depression "with atypical features" made it into the DSM-IV in 1994, which is the equivalent of "tweet" making it into Merriam-Webster in 2011. The Diagnostic and Statistical Manual of Mental Disorders is the official guidebook for professionals of the psyche. It's also part of how health insurance companies figure out whether they have to pay for your therapies or not.
The DSM-IV's criteria for diagnosing an episode of atypical depression requires, first and foremost, that the person has mood reactivity -- meaning that, at times, he or she can feel up to 50 percent better in response to a happy event.
It also specifies that the patient exhibit two of these four symptoms: overeating, oversleeping, leaden paralysis and sensitivity to rejection that affects quality of life.
Rejection sensitivity is one of the more interesting aspects of atypical depression. People who exhibit this symptom have serious work and social troubles because they overreact to any hint of criticism or rejection. Instead of taking a boss's comments in stride, they may go into a full-blown depressive episode. The terror of being rejected makes it very difficult for them to have romantic relationships and maintain friendships; a small slight or off-hand comment can validate their worst fears.
The other symptoms are, perhaps, easier to quantify. Overeating can be measured by a weight gain of 5 pounds (2.27 kilograms) or more. Oversleeping can be defined by sleeping 10 hours a day (counting naps) or 2 hours more than usual on a regular basis. Leaden paralysis usually lasts for an hour or more a day.
Some compensate by setting up rigid sleep and meal schedules and avoiding relationships. But bridging gaps in feeling OK doesn't make those holes disappear.
So how do you treat the symptoms that make everyday life so difficult?