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"Does Milk of Magnesia reduce constipation?"

ZocdocAnswersDoes Milk of Magnesia reduce constipation?


Does Milk of Magnesia help reduce constipation in the long term? I know that it works fine as a short term solution, but I want to make sure that I have regular bowel movements as I get older - and I already have a lot of fiber and water in my diet.


As you correctly pointed out, Milk of Magnesia (MoM) is a good short term solution for constipation, however it is a poor long term solution. MoM is an osmotic laxative, which essentially means your bowels can not absorb the magnesium hydroxide in the solution and so it travels all the way down into your colon where is acts as an osmotic load to pull water into the colon. this distends the colon and stimulated the nervous system of your gut to contract the muscle walls in your bowel (this is called peristalsis) and expel the contents of the bowel. the result is normally a large, loose and watery bowel movement. For many reasons, milk of magnesia is not a good long term solution for constipation. The main reasons are due to the fact that is can lead to dehydration as well as electrolyte imbalances (specifically low potassium) which can lead to dangerous health conditions (such as cardiac rhythm disturbances). So, what to do for long term assurance of regular bowel movements? the best solution, as you have rightly pointed out, is to drink an adequate amount of water and to increase your fiber intake. This means at least 8-10 twelve ounce glasses of water per day and a diet rich is whole grains and vegetables. in addition, many patients find supplemental fiber, in the form of psyllium husk (metamucil), on a nightly basis is helpful to keep there bowel movements regular. hope this helps!

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