Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Atypical Depression (AD) is a subtype of Dysthymia and Major Depression characterized by mood reactivity — being able to experience improved mood in response to positive events. In contrast, sufferers of "melancholic" depression generally cannot experience positive moods, even when good things happen. Additionally, atypical depression is characterized by reversed vegetative symptoms, namely over-eating and over-sleeping.
Despite its name, "atypical" depression is actually the most common subtype of depression[2][3] — up to 40% of the depressed population may be classified as having atypical depression.
The DSM-IV-TR, a widely used manual for diagnosing mental disorders, defines Atypical Depression as a subtype of depression or dysthymia, characterized by Atypical Features:
By the ICD-10 classification, it will fall in the category of F32 or F39.
In general, atypical depression tends to cause greater functional impairment than other forms of depression. Atypical depression is a chronic syndrome that tends to begin earlier in life than other forms of depression — usually beginning in teenage years. Similarly, patients with atypical depression are more likely to suffer from other psychiatric syndromes such as panic disorder, social phobia, avoidant personality disorder, or body dysmorphic disorder. Atypical depression is more common in females — nearly 70% of the atypical population are women[citation needed].
Medication response differs between chronic atypical depression and acute melancholic depression. While some studies[citation needed] suggest that an older class of drugs, MAOIs, may be more effective at treating atypical depression, the modern SSRIs are usually quite effective, while the tricyclic antidepressants are not. In addition, SSRI response can often be enhanced with "booster" medications. And, medication treatment works best when combined with appropriate psychotherapy.[4] It is important to remember that such co-morbid syndromes as panic disorder may not be fully treated without additional medication.
It has been noted that patients with atypical depression often suffer from intense cravings for carbohydrates. A mineral supplement, chromium picolinate, was found to assuage these cravings in one study, though the conclusion reached has not been replicated.
Some hypothesize that atypical depression may be related to thyroid dysregulation. Some studies have found subtle thyroid abnormalities in people with atypical depression. Another study suggests that patients may benefit from triiodothyronine, a medication used to treat hypothyroidism[citation needed].