Hi Nurse Melissa:
What is your take on using milk of magnesia as a deodorant? I have had very disappointing results with a myriad of deodorants. I tried MOM and surprisingly, it works for me! But now I’ve discovered that it contains sodium hypochlorite as a preservative and that it’s actually bleach. Should I be concerned about using it on my skin?
Milk of Magnesia’s active ingredient is a mineral called magnesium hydroxide. It’s slightly alkaline and is used as a drug treatment for stomach upset and a laxative. However, it has been used for such varied purposes as skincare, dental care, and deodorizing. The alkalinity of magnesium hydroxide may be one way in which the product works so well for so many treatments. But, as you mentioned, looking more closely at the label of many brands of Milk of Magnesia you’ll find listed in the “inactive ingredients:” sodium hypochlorite. It is misleading for internet articles to try to scare people by saying it is bleach. What many might think of is household bleach (chlorine bleach), which also usually contains sodium hypochlorite. However, the amounts would be quite small in Milk of Magnesia due to its very low concentration, very similar to how it is used for disinfecting drinking water in North America and Europe. The anti-bacterial activity of the sodium hypochlorite kills odor-causing bacteria. This anti-bacterial property may be another way in which Milk of Magnesia works well as a deodorant.
As with most products, it is good to educate yourself on what it is you are using on your body. So, I applaud you for asking this question on GGC. I hope this information allows you to make an informed decision. Considering Milk of Magnesia is ingested by many people for stomach upset and a laxative, and if it is working for you as a deodorant, and it is not visibly irritating your skin, then you may consider continuing use. However, if you are concerned about sodium hypochlorite, you could look into Milk of Magnesia brands that have zero-additives (i.e. GoodSense, Kroger, TopCare, Walgreens) and hope that it is the alkaline magnesium hydroxide that is working as a deodorant for you, not just the disinfecting sodium hypochlorite.