two bottles of Milk of Magnesia (MoM) laxative

One particular misery of hot summer days is heat rash. Warm muggy weather tends to make people sweat; if sweat glands get blocked, the result is an itchy, prickly red rash. What can you do to ease heat rash?

Milk of Magnesia for Heat Rash:

Q. I am in my late seventies, and my breasts are very large. In hot weather I used to have a serious problem with heat rash. Various creams and lotions didn’t help much. Then I tried milk of magnesia, and that took care of the problem.

As soon as I dry off after my shower, I rub milk of magnesia into my skin. No more heat rash.

A. Thank you for sharing your solution to this common complaint. Many women have found that “bra itch” is just as troublesome for them as jock itch can be for men.

One reader told us his story about using MoM:

“I am a man who has used MoM (milk of magnesia) to quickly and effectively treat both underarm rash and a rash in the genital area. The doctor recommended treating them with standard anti-fungal treatments, to no avail. I saw this and tried it and now swear by it. What a relief!”

Milk of magnesia (magnesium hydroxide) has drying properties when used on the skin. People report success using it for underarm odor, seborrheic dermatitis and acne.

Here is what one reader reports about using it for heat rash:

“I used MOM on a terrible heat rash in the private area between legs and body and even on privates, and it cleared it up in a very few days. It amazed me after using all types of medications such as calamine lotion, Solarcaine, and medicated powders, that this simple remedy would work so quickly in relieving terrible pain and itch.”

Others have found MoM useful on poison ivy, rosacea or eczema:

“Milk of Magnesia is FANTASTIC for rosacea, and it does a pretty good job on eczema. I use a cotton pad and dab it on affected areas morning and night. Let it dry, then apply whatever lotion or moisturizer you normally use. The moisturizer/lotion will make the white residue from the MoM disappear. Also, people with rosacea should not use foaming cleansers or toners with alcohol. They are too harsh chemically. Use cream cleansers instead. (I don’t use toners at all.)”

You can learn more about milk of magnesia for topical use here.

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  1. cpmt

    listerine has the same effect too.

  2. cpmt

    Uppss: rash, sorry.

  3. CH
    Charlotte, NC

    The People’s Pharmacy Milk of Magnesia Deodorant (MoM) works great for me, as a deodorant, and as a treatment of irritation under the breast and in the groin area. I love it as a deodorant – I use the plain MoM deodorant and I think it works better than Secret. I just dry it after application with my hair dryer or by fanning it. I do the same for under my breasts daily and when needed in the groin. No more irritation!

  4. Judith

    I would love to use M. of Magnesia, but for some strange reason it is not available in New Zealand!

  5. Laura

    I finally figured out that the itch that follows sweating along my bra line is actually a latex allergy. Finding a latex free bra has proved impossible, so now I wear all my bras inside out/outside in. Usually the the latex is on the inside, but the outer covering is a smooth satiny fabric. It has made a wonderful difference!

  6. Debbie

    I too have large breast and a rash under them. I bought MoM unscented deodorant from your pharmacy and now I roll on under breast after shower. No more rash !!

  7. Saz

    I’ve suffered from a heat rash on my back since I was a teen. I’m now 51 and I’m still living with it. When I became active in sports I noticed it and still have it because I enjoy working out. I’ve seen four dermatologists and tried anything from creamers to medicated shampoos. What keeps it in control is hydrocortisone cream and occasional baby powder with cornstarch.
    Nevertheless it never completely goes away and as you may assume is at its worst in the summer months. I’m now trying MOM. It’s been two days. I thought I would see better results. I’ll give a little while longer. I presume I’ll be back using hydrocortisone cream for the control factor.

  8. M.C.C.

    I consulted a Dermatologist for rash under my breasts. He prescribed Econazole Nitrate Cream 1%. I have been using for 5 days, and seems the rash is spreading, almost like a ring worm. I use it twice a day, as prescribed, after my shower, and before I go to bed at night. He told me to use it for 4 weeks. And that after all is gone, buy an anti-fungus talcum powder, to use it regularly. Should I let it continue and see what happens, I would like to try the M.O.M. I thought I read in the newspaper column “The People’s Pharmacy” about using corn starch. Thank you for any help I can get.

  9. JW

    I have had a terrible rash under bra area and panty line area. Bleed and has terrible odor and very painful, HELP
    People’s Pharmacy response: This problem should be checked by a physician who can make a diagnosis. It might be something more serious than the usual skin fungus treatable with home remedies.
    Here are some home remedies:

  10. RAD

    I have had a problem with under-breast rash for years. My Doc has prescribed several different anti-fungal meds. Some have worked, but when I sweat a lot the meds don’t work well, because my bra rubs the skin with the sweat and I can’t keep it dry enough.
    An idea popped into my head, when I was thinking how can I keep the skin dry….I realized that I needed a barrier between the bra and skin, THAT IS WHEN I STARTED USING TANK-TOPS. I now wear a tank-top or thin t-shirt now under all my bras and tops when not wearing bras. I just tuck the tank-top under my breast and it keeps the breast skin all dry. When wearing a bra I just put the bra on over the tank-top and use the bra to tuck the barrier shirt under with the bra cups. I have been rash/sore free for about 3 years now. I don’t need any more expensive cremes or meds and I just change more often when I sweat a lot. Hope this helps you all.

  11. Pat

    I tried Milk of Magnesia for a rash under my breasts. It worked well but was hard to wash off and took a long time to dry. I switched to white vinegar morning and night and I think it works just as well. I pour a little bit in my hand and splash it on. (White vinegar will not stain the tile grout around my bathroom sink, apple cider vinegar stains and is hard to clean off.)

  12. Helen M

    I have begun using vasoline as a barrier cream; my problem is intertrigo then yeast infections that can come out in an hour’s time, weep, and hurt. I find this better than the barrier cream I was using before. However, I do use MoM for my underarms’ odor control, I think I will try it under my breasts too. I have to be careful as a breast cancer survivor.

  13. kay_serasera

    (I think you hesitate to mention brand names on your site, but maybe you will make an exception.)
    This kind of chafing is dreadfully painful. Monistat makes a unique product called Soothing Care Chafing Relief Powder Gel that has been an absolute lifesaver for me. I’m glad to hear about milk of magnesia and will definitely try it, but also highly recommend this powder gel, especially when chafing has already occurred. It instantly soothes the pain, stops further chafing, and does not wet or stain clothing.

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