The National Institutes of Health defined premenstrual syndrome (PMS) as physical and psychological symptoms that arise about a week to 10 days before women get their monthly period.

The Mayo Clinic reported an estimated three of every four menstruating women experience some form of premenstrual syndrome. This tends to peak during the late 20s and early 30s. NIH added PMS symptoms typically get worse as women approach the transition to menopause.

WomensHealth.gov wrote PMS is different for everyone. Most women have fairly mild symptoms while small amounts have a severe form of PMS, called premenstrual dysphoric disorder (PMDD).

University of Maryland Medical Center (UMMC) said while the exact cause of PMS is unknown, popular theories include hormonal changes such as too much estrogen or not enough progesterone, low levels of vitamin B6 or other nutrients, abnormal metabolism of hormone-like substances called prostaglandins, and low levels of the brain chemical serotonin.

WomensHealth.gov said PMS can cause both emotional and physical symptoms. These include acne, swollen or tender breasts, fatigue, insomnia, upset stomach, constipation, or diarrhea, headache or backache, appetite changes or food cravings, joint or muscle pain, trouble with concentration or memory, tension, irritability, mood swings, crying spells, anxiety or depression and weight gain due to fluid retention.

NIH said other symptoms are poor judgment; feelings of guilt, increased fears; slow, lethargic movement; less tolerance for noise and light and changes in interest in sex.

Although this list of symptoms is long, the Mayo Clinic said most women with PMS experience only a few.

WomensHealth.gov cautioned PMS symptoms usually disappear after the bleeding starts, but sometimes continue for the first few days of the period.

PMS treatment options include lifestyle changes, medications and alternative therapies.

For mild PMS, WomensHealth.gov said lifestyle changes include regular exercise, eating healthy; avoiding salt, sugary foods, caffeine, and alcohol; not smoking; and getting enough sleep.

Common medications for PMS are non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen which can ease headache and cramping. Others are hormonal contraceptives, such as birth control pills. The Mayo Clinic wrote these stop ovulation and stabilize hormonal swings.

In severe cases, antidepressants, like selective serotonin reuptake inhibitors (SSRIs) may be helpful. The Mayo Clinic said they can reduce symptoms such as fatigue, food cravings and insomnia and are the first-line agents for treatment of severe PMS or PMDD.

Alternative therapies include certain vitamins and minerals such as folic acid, calcium with vitamin D, magnesium, vitamin B-6, and vitamin E.

WomensHealth.gov said these may help relieve some PMS symptoms. Some women find relief with supplements like black cohosh, chasteberry and evening primrose oil. Consult a doctor before taking any of these.

Sources:

Premenstrual syndrome (PMS) fact sheet. WomensHealth.gov by the Office on Women's Health in the Office of the Assistant Secretary for Health at the U.S. Department of Health and Human Services. Web 29 Jan 2012.
http://womenshealth.gov/publications/our-publications/fact-sheet/premenstrual-syndrome.cfm

Fact sheet: Premenstrual syndrome. NCBI.NLM.NIH.gov by the National Center for Biotechnology Information and U.S. National Library of Medicine. Web 29 Jan 2012.
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0005209

Premenstrual Syndrome. NCBI.NLM.NIH.gov by the National Center for Biotechnology Information and U.S. National Library of Medicine. Web 29 Jan 2012.
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002474

Premenstrual Syndrome (PMS). MayoClinic.com by Mayo Foundation for Medical Education and Research. Web 29 Jan 2012.
http://www.mayoclinic.com/health/premenstrual-syndrome/DS00134

Premenstrual Syndrome. UMM.edu by University of Maryland Medical Center (UMMC). Web 29 Jan 2012.
http://www.umm.edu/altmed/articles/premenstrual-syndrome-000132.htm

Reviewed January 31, 2012
by Michele Blacksberg RN
Edited by Jody Smith