Differentiate between premenstrual syndrome (PMS) and premenstrual dysphoric disorder (PMDD).

Women with premenstrual syndrome (PMS) experience bodily discomfort and emotional distress for up to two weeks, from ovulation until the onset of menstruation. As many as 75 percent of menstruating women report one or more premenstrual symptoms; 3 to 9 percent experience disabling,
incapacitating symptoms. Once dismissed as a psychological problem, PMS has been recognized as a very real physiological disorder. Among the many symptoms of PMS are mood swings, anxiety, forgetfulness, impaired judgment, digestive distress, hot flashes, dizziness, headaches, changes in appetite, water retention, breast tenderness, and insomnia.

Premenstrual dysphoric disorder (PMDD), which is not related to PMS, occurs in an estimated 3 to 5 percent of all menstruating women. It is characterized by regular symptoms of depression (depressed mood, anxiety, mood swings, diminished interest or pleasure) as well as physical symptoms, such as changes in appetite, energy, weight, or sleep during the last week of the menstrual cycle. Women with PMDD cannot function as usual at work, school, or home. They feel better a few days after menstruation begins.