Is premenstrual dysphoric disorder a distinct clinical entity?

Does the evidence now available support the concept of premenstrual dysphor ic disorder (PMDD) as a distinct clinical disorder such that the relative s afety and efficacy of potential treatment can be evaluated? In a roundtable discussion of this question, a wealth of information was reviewed by a pan el of experts. The key characteristics of PMDD, with clear onset and offset of symptoms closely linked to the menstrual cycle and the prominence of sy mptoms of anger, irritability, and internal tension, were contrasted with t hose of known mood and anxiety disorders. PMDD displays a distinct clinical picture that, in the absence of treatment, is remarkably stable from cycle to cycle and over time. Effective treatment of PMDD can be accomplished wi th serotinergic agents. At least 60% of patients respond to selective serot onin reuptake inhibitors (SSRIs). In comparison with other disorders, PMDD symptoms respond to low doses of SSRIs and to intermittent dosing. Normal f unctioning of the hypothalamic-pituitary-adrenal (HPA) axis, biologic chara cteristics generally related to the serotonin system, and a genetic compone nt unrelated to major depression are further features of PMDD that separate it from other affective (mood) disorders. Based on this evidence, the cons ensus of the group was that PMDD is a distinct clinical entity. Potential t reatments for this disorder can now be evaluated on this basis to meet the clear need for effective therapy.