The premenstrual syndrome (PMS) refers to a constellation of symptoms that occur just prior to the onset of menses (ie, during the luteal phase, or second half of the menstrual cycle). Patients often experience cyclic psychiatric and/or physical symptoms that interfere with their daily activities. These issues will resolve with the onset of menses.

It is estimated that up to 80% of women experience some degree of premenstrual symptoms, with approximately 5%-10% of women meeting the criteria for PMS and 2%-3% meeting the criteria for the more severe version called premenstrual dysphoric disorder (PMDD).

Diagnostic criteria for PMS include having at least one symptom of depression, anger outbursts, irritability, anxiety, social withdrawal, and confusion and one symptom of breast tenderness or swelling, abdominal bloating, headache, weight gain, joint or muscle pain, and extremity swelling. These symptoms must occur for at least 3 consecutive menstrual cycles within 5 days of the onset of menses and resolve within 4 days after the onset of menses.

The etiology of PMS is unknown. It has been thought it could be related to fluctuations in hormones, but often testing reveals normal hormone levels in these patients. Despite this, patients often have symptom improvement or resolution with menopause or with hormonal suppression.