Premenstrual dysphoric disorder: An unusually severe form of premenstrual syndrome characterized by drastic mood swings, anger, depression, irritability, tension, sleep and appetite changes, fatigue, and physical problems such as pain or bloating. Abbreviated PMDD. Symptoms generally begin the week before menstruation and end a few days after menstruation has begun. Treatment can involve the use of antidepressant medications of the SSRI (selective serotonin reuptake inhibitor) type.
