Premenstrual dysphoric disorder (PMDD) can be considered to be a severe form of premenstrual syndrome (PMS).  Both PMS and PMDD are characterized by unpleasant physical and psychological symptoms that occur in the second half of a woman's menstrual cycle, most commonly in the days preceding the menstrual period.  Fatigue, mood changes, irritability, and abdominal bloating are among the most common symptoms of PMS and PMDD, but numerous other symptoms have been reported.

PMS is much more common than PMDD.  PMS may affect to 30% of women with regular menstrual cycles, while only 3% to 8% of these women have true PMDD.

Although the precise cause of PMS and PMDD is unknown, it is believed that these conditions result from the interaction of hormones produced by the ovaries at different stages in the menstrual cycle (such as estrogen and progesterone) with the neurotransmitters (chemicals that serve as messengers) in the brain.  While the ovarian hormone levels are normal in women with PMDD, it is likely that the brain's response to these normally-fluctuating hormone levels is abnormal.

Herbs, supplements, homeopathic remedies and bio-identical progesterone can help to alleviate symptoms of P.M.S.