You just can’t win: First, you’re constipated; then just days before period you’re running to the bathroom with diarrhea and What gives? This is another effect of the hormonal fluctuations trigger your period.

After ovulation, when progesterone levels initially increase, relax the smooth muscles in the body, such as the gut. The level of progesterone leads to slower muscle contractions, which lead to bloating, indigestion, and constipation.

But after ovulation, estrogen levels drop and continue When the levels of both estrogen and progesterone fall, prompt cramping and diarrhea. Voilà! First, constipation, followed days later by diarrhea.


Another theory for PMS-related diarrhea has to do with which are hormone-like substances that cause contractions and cramps. Some studies have suggested that with digestive problems complain of more severe PMS symptoms than those without digestive problems. Experts theorize the involved in both menstrual and digestive problems are Since prostaglandins prompt both uterine contractions and of smooth muscle in the bowels, they are suspected in (painful periods), intestinal disorders such as irritable syndrome, and some PMS symptoms such as cramps and diarrhea.


Prostaglandins are a group of hormone-like substances produced in the cell membranes of body tissues. They may affect blood pressure, metabolism, and smooth muscle activity. Some prostaglandins reduce inflammation. Synthetic prostaglandins are used to induce labor.

The Everything Health Guide to PMS Although uncomfortable, PMS-related diarrhea subsides with your period. In the meantime, do what you can to minimize symptoms: eat smaller meals, avoid foods that cause or intensify it, and use over-the-counter medications, if necessary. Here are some treatments for diarrhea you can try at home:

  • Keep hydrated with sports drinks, which replace the body’s electrolytes.

  • Try the BRAT diet. Pediatricians and other physicians recommend this bland diet of bananas, rice, applesauce, and toast to ease diarrhea and nausea.

  • Practice good hygiene to reduce the spread of germs.

  • Try over-the-counter diarrhea medications.

  • Consider taking evening primrose oil.

Evening Primrose Oil

Many alternative practitioners recommend evening primrose oil, or EPO, for PMS symptoms. This herbal remedy contains an essential fatty acid called gammalinolenic acid (GLA) and is known as prostaglandin precursor. Alternative medicine practitioners believe evening primrose oil is beneficial for many conditions, including irritable bowel syndrome; it is said to alleviate this condition in women during their premenstrual and menstrual phases. However, to date, there is insufficient medical evidence, in the form of controlled, systematic studies, to show that evening primrose oil reduces PMS symptoms.

While evening primrose oil has its proponents in alternative medicine, a number of clinical studies have found insufficient evidence to support its use or have concluded that it does not provide any relief for PMS. In contrast, one study from the Cedars-Sinai Integrative Medicine Medical Group, published in 2000 in the Journal of the Pharmaceutical Association, Washington, D.C., found that EPO was a reasonable treatment for some women with PMS.

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