Magnesium sulfate, better known as Epsom salts, is a commonly used remedy for constipation. Although people might perceive Epsom salts as a "natural" and "safe" laxative, its use can have side effects and potentially serious consequences. MayoClinic.com urges patients with chronic constipation to try diet and lifestyle changes before turning to Epsom salts or any other type of laxatives.
Dehydration
The Merck Manual states that osmotic agents for constipation, like Epsom salts, are generally safe even if used regularly. However, because of how they act to ease constipation, they can cause dehydration. The digestive tract cannot easily absorb the magnesium ions in Epsom salts, so they stay in the lumen or tunnel of the intestines, where they draw in excess water to maintain an osmotic balance. The influx of water into the large intestines increases their volume and pressure, which stimulates peristalsis, the muscular contractions that move fecal matter through the bowels. As a result, people usually have a bowel movement within about 3 hours of taking oral Epsom salts. However, the net movement of water into the intestines can cause systemic dehydration, and in some cases diarrhea, and people who use Epsom salts should be aware of the possibility and drink more fluids in compensation.
Magnesium Toxicity
Magnesium is an electrolyte, an ion with important properties in the body. Electrolytes regulate nerve and muscle function and are especially important in maintaining the normal rhythm of the heartbeat. Although Epsom salts work as a laxative because magnesium is not readily absorbed, drawing water into the intestines to counteract the magnesium concentration, some of the magnesium does enter the cells and could build up to dangerous levels. MayoClinic.com and the Merck Manual warn that prolonged, frequent or large doses of oral Epsom salts or other osmotic laxatives can produce an electrolyte imbalance, with the potential to cause abnormal heart rhythms, confusion, weakness or seizures.
Abdominal Cramps
The bulk movement of water into the intestines caused by Epsom salts, and the peristalsis it triggers, can lead to uncomfortable abdominal cramping. Unusually intense muscle contractions pushing the fecal matter through the intestines can be painful, and can even cause fecal incontinence in some cases. The risk of abdominal cramping is not unique to Epsom salts: stimulating laxatives, which directly intensify intestinal smooth muscle contraction, also frequently cause cramping. Bulk-forming laxatives such as fiber supplements are the gentlest types of laxative. They are unlikely to cause cramping or any other side effects and are safe for regular use, according to MayoClinic.com.
Member Comments