Q How common is premenstrual syndrome (PMS)?

Dr. Engle: About 75 percent of women experience some symptoms of PMS, including some combination of irritability, fatigue, mood swings, food cravings, breast tenderness or bloating. PMS starts anytime from the middle of a woman's cycle, when ovulation occurs, until menstruation begins. Symptoms resolve shortly after a woman gets her period.

PMS is not the same as PMDD, which stands for premenstrual dysphoric disorder. PMDD is a more severe form of PMS and is less common, affecting between 3 and 8 percent of women.

Q What causes PMS?

Dr. Engle: Hormonal spikes and variations associated with menstruation affect a woman's serotonin level, a brain chemical that affects emotions. Hormonal fluctuations, stress or being overtired can make PMS more difficult to cope with during some months than others. The hormone swings that occur during perimenopause, the years leading up to menopause, can make PMS more severe for women as they get older.

Q What can I do about it?

Dr. Engle: Lifestyle changes can help-exercise, reduce caffeine, go easy on salt and simple sugars, take 1,200 mg calcium and 400 IU vitamin E a day, and eat foods rich in vitamin B, like broccoli.

Talk to your doctor if PMS is affecting your life or the people around you. We've found that some antidepressant medications can provide relief from PMS. Research has shown that an SSRI (selective serotonin reuptake inhibitor) like Sarafem or Zoloft can be effective when taken to relieve symptoms. The medication is taken either daily for the two weeks before menstruation or when symptoms occur. Side effects that occur when taking an SSRI continuously, such as decreased libido, can be avoided when the SSRI is taken intermittently.

Eileen Engle, MD, is the Director of Women’s Services at Doylestown Hospital.