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How Soap in the Bed Eases Leg Cramps--A Hypothesis

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by Derek H. Page

There is far too much anecdotal evidence to dispute the fact that soap at the bottom of the bed can relieve nocturnal leg cramps. But contributors to this column have been pleading for a scientific explanation ever since the subject was first raised, nearly twenty years ago. Even after years of discussion there is no consensus on the mechanism. How does the soap ward off the initiation of a cramp? For the leg to be influenced by a signal initiated by the soap, something physical must link from soap to leg.

A crucial clue comes from the work of Professor Ough (1). He found that soap contains a natural scent molecule that has antispasmodic properties. When a transdermal patch was applied using soap as the active ingredient, the severity of menstrual cramps could be diminished. However, Ough does not state precisely how this result can explain why cramps can be alleviated in a leg remote from the active source. How can the scent molecule be transmitted from its place in the bar to the leg muscle?

My colleague and I address this point (2,3). We also suggest that a scent molecule is responsible (whether it be the added fragrance or a natural fragrance). Being volatile, it evaporates from the surface of the bar and deposits on the leg. The molecule is small enough to pass through the skin as in the widely accepted transdermal patch technology. Being vasodilatory, the molecule relaxes the smooth muscles in the leg, increases the local blood supply and thus soothes the cramp. This hypothesis fits all the known evidence. It explains why after some weeks the soap becomes inactive. As the bar ages it dries out and its surface becomes harder and more resistant to the passage of scent molecules. The bar can be rejuvenated by scraping it, thus exposing newer and moister surfaces.

However, the anecdotal record allows for an alternative hypothesis as follows. The active agent, as in the previous hypothesis, is the vasodilating scent molecule. In this hypothesis, however, it is transmitted to the leg by the simple but uncertain process of accidental touch. Soap is soft, and any contact between the soap and the leg is bound to leave some soap behind. In addition soap will be transferred to the sheets which will in turn transfer back to the legs. Movement of the legs in the night may be sufficient to transfer soap to the legs which relieves cramps as described earlier. The anecdotal evidence supports this mechanism. There are cases of successful relief reported in which soaps were rubbed against the calf muscles. Most significantly, the effect of aging of the soap bar, which supported so well the other hypothesis, fits this one also. As the bar of soap ages, its surface becomes firmer and more resistant to transfer by abrasion.

So there we are. We have two hypotheses, neither of which can be disproved by existing data. There is however a very simple experiment that could allow us to determine whether transfer occurs in the vapour phase or only by direct contact. Any reader who has had severe leg cramps and who has been completely cured by placing soap at the foot of the bed can do it.

Use a bed in a spare room that hasn't been slept in for a couple of weeks and has fresh sheets. Place the soap in a plastic container that prohibits physical contact between the soap and the leg. It must, however, permit easy passage of the scent vapor. Ensure the container is not contaminated on the outside with remnants of soap. Place in the container a couple of bars of soap that you know from experience work. Put the container at the foot of the bed between the sheets and leave it there for at least a few hours to equilibrate. Check that you can smell the scent by putting your head under the covers. Have a shower (without soap!) and get into bed. If you have a cramp in the night you can conclude that vapour phase transfer of the scent molecule is not sufficient to protect the leg from cramps. If you have no cramp the vapor phase transfer mechanism is confirmed.

1.Ough, Y.D., Journal of Alternative and Complementary Medicine, July 2008,14(6) 618
2. Page, D.H. and Smailes, H.,, July 22, 2012
3. Page, D.H., July 26, 2012

This hypothesis was submitted by guest blogger Derek H. Page. We invite you to share your experience below, particularly if you are inspired to carry out his suggested experiment. Should you wish to read some startling "soap stories" here is a link.

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I have used several bar soaps which are no longer useful in the shower because they have become too small. I place these under the top sheet. My legs may touch the places where the soap is under the sheet, but it doesn't touch my legs and is possibly no longer fragrant due to its use and age. (my sense of smell is poor)

I tried this with a bar of soap that had sat around unused for about 20 years and it worked, much to my surprise, immediately and efficiently. According to the article, the surface would have been too dried out to be effective.

Response from Derek Page: I'm not an expert on soaps, but some soaps contain humectants that keep the bar moist. Dove is one of these. Perhaps that is why it seems to retain its "curative" power.

I have used the same bar of soap for at least 5 years. It still works! It's a Dove bar. I have never scraped it to refresh the smell, but I'll try it. Just another comment - yellow mustard worked fantastically on my burned fingers! Got this from your site too.

Response from Derek Page: Dove contains humectants to keep it from drying out, which may help explain why it is active for so long.

If scent is the key, then wouldn't some kind of lotion on the legs before sleep also help?

Response from Derek Page: Thank you Mbcoats. That I think is essentially what Professsor Ough did. (Pronounced 'Oh', by the way. ) He took an extract (a scent oil) from the soap and applied it in a patch to the region of pain in cases of fibromyalgia and menstrual cramps, both with success. To my knowledge he did not do the same with cases of leg cramps.

The bar of soap in my sock at night stops the restless leg problem, helps with the tendenitis I sometime suffer from the Achilles heel problem I have on one foot..don't know it works but it does.

I do not unwrap the bar of Dial Soap that I put under the sheet. Cannot detect fragrance through the wrapping. I replace the bar whenever I need a new bar in the shower, using the one under the sheet. For at least five or so years, this has prevented the nightly leg cramps I used to have.

Could people that currently use soap under the sheet reply as to which brand of soap that they use. Attempt would be to see if there is a most effective brand of soap to use--or if the brand matters at all. Thanks for your contribution.


We have heard repeatedly that Ivory or Irish Spring are especially effective, though people can get relief from "free" hotel soap that they took home.

You may also wish to check out our Bed Soap and Leg Soap. We created a flat bar so that it is less likely to be uncomfortable in bed.

Here is a link:

How do you keep a bar of soap in your socs and not have it uncomfortable or how can you keep soap in along with your foot? I am asking because I have the same heel problem and am trying for heels (both feet) not to hurt.


This is precisely why we created/designed "Leg Soap." These small-sized soap chips fit comfortably inside socks. No smashing, shaving or crushing soap necessary. Just pull a soap chip out of our box and away you sleep or on a walk.
Here is a link:

For some reason, the last 2 years my knees have ached terribly when I lie down in bed. No pain at all when standing, walking, sitting - just lying down. I figure it's some kind of arthritis, but really don't know what is causing it.

Your soap remedy kept popping up in your newsletter, so 6 months ago I finally decided to try it for my knees. It was amazing! In one night, the pain was totally gone.

On vacation, I spent a few nights in another bed with no soap & guess what - knees ached again. So I bring my soap with me now. I replace it every time I need a new bar in the shower.

I won't sleep without it! Thank you for all your wonderful tips!

After reading about the soap for leg cramps, I have for many years put a bar or more in a pillow case or knot'd sock at the bottom of my bed. It works... I found that Ivory soap works well and also Dial.

Also another hint from this site was the black pepper to stop bleeding. I cut my hand really bad, piled black peeper on the cut and stopped the bleeding. Seem to heal quickly. Thank you for all your information on this site.

I cannot tolerate scents, so I use an old bar of Neutrogena unscented soap, still in its clear wrapping. And yes, it works.

I have actually found that this does help a bit as well. But I have yet to try the soap trick so cannot compare.

Could Bar Soap possibly relieve headaches?

Response from Derek Page: According to Professor Ough, the soap-scented patch is not an anesthetic. It relieves pain by relaxing the muscles. Consequently it works on headaches associated with fibromyalgia but not on headaches from other causes.

Ivory soap worked so well, that mom tried to put it in her socks! so she shredded some on a kitchen scraper and sewed in side of a pouch, mom said they were comfortable in socks and no more cramps how about making a talcum soap powder and sprinkling in just like talcum.

For several years now I have been putting a bar of soap in my bed under the top sheet for leg cramps. This works almost immediately and the cramps are gone.

You and readers might find this hard to believe but it is true. For almost a year now, I have had severe pain in my left leg from my waist to my ankle and this is only at night (an MRI indicated bursitis).

Most nights I would have to get up between 2:00 a.m. and 5:00 a.m. and get in my recliner because the pain kept me from sleeping.

Late one night when the pain was so bad, I thought about the soap and wondered if it could possibly help with the pain. I put a bar of soap next to the hip/thigh area where the pain started and within minutes the pain stopped!!!!!!!!!!! I couldn't believe it!

For several months now, I have done this every night and can finally get a good night's sleep with NO PAIN !!

I told a friend who has back and hip pain about this and he tried it and was surprised when it worked for him, too. It's hard to believe this works but my husband is my witness.

Thank you,

Lynda H.

I don't think either theory hits home.
I have used soap for years. Irish spring works best, but I have a couple bars of ivory, in their wrappers.

I am convinced that it has something to do with the fact that real soaps are made with ingredients with /carry a positive molecular charge. Calcium/magnesium have positive charges, I am told. I believe that cramps and restless leg feelings are a build up of electrical charges, similar to how epilepsy is misfiring of electrical. Also like a build up of charge when static builds up in dry winter and you touch something that causes the electrical charge to discharge and move into another object.
I think the buildup in legs/muscles, etc., dis charges into the positively charged soap.

Well I used the soap under the sheets for 2 years. I used soap I received while staying in hotels. I never took it out of the plastic wrappers. Now could you still smell the scent? Yes. Since I took the soap out from under my sheets, over a year ago, my leg cramps have not returned, at night. I still get leg cramps during the day. I would put the soap back under the sheets in a heartbeat if my leg cramps return at night. It worked for me.

I suffered an event of transverse myelopathy over a year ago, and one of the lasting effects has been tight muscles and cramping in my leg muscles, esp at night... after 5 of these night time cramp events, decided to try a perfumed bathbar from World Market (was a gift), and NO more cramps! After 3 months under my sheets, it's still working...

I have used the soap bar in my bed for years and it works. One night my legs were so bad I couldn't sleep. I was visiting my daughter and went into the bathroom to get a bar of soap but could only find the used one on the sink. Went back to the bedroom and found the soap had fallen out of the sheet. Thereafter, no problem.
One night while playing cards both of my hands cramped up so bad (never happened before). I fortunately thought of the soap for the legs, got a bar and worked it in my hands. Immediately the cramps were gone and I have never had them since.

A few months ago I had my 3rd back surgery and for the last 10 years or so I have experienced periodic leg cramps. Some were very severe with burning.

I heard about this technique from my physical therapist. Knowing that I had some very bad nights he told me about it, but he was skeptical. I told him I would try anything to alleviate this pain.

So, I did as he had heard. Put a bar of open soap in a zip-lock baggie and put it under my mattress. It works like a charm. I've told my whole family about it. My sister and brother both have MS and it seems to work for them as well. Diabetes also runs in my family and it helps those members too.

I'm sold!

My story is similar to Linda's: There was a time when my husband complained almost daily about something like sciatica nerve pain from his hip down his leg. I hated that he had to suffer this, so unbeknownst to him, I put one bar of Ivory soap at the foot of each side of our king-size bed. I put them between the mattress pad and the bottom sheet to help hold them in place.

This is Ivory bar soap, still in its paper wrapper. They often get pushed to the very end of bed, not in direct contact with our feet. I sorta push them up a little each morning when I make the bed. My husband hasn't mentioned the sciatica for a long, long time. I might change the soap once a year, nothing fussy about it.

This truly works, my husband fought his restless legs all night until I put Ivory under his sheets.

I have used mustard and bar soap with success for leg cramps and rest less leg syndrome. Amasing but it works. EMB

I've not tried the soap remedy yet for restless leg syndrome. Would like to share an "off label" remedy for this miserable condition that I found by accident. When I stopped smoking July '12, I was smoking 5-6 cigarettes per day - a major reduction over a 2 year period from a pack a day. Restless legs evidenced during this 2 year period. I've used the Nicorette Mini Lozenges (like Tic-Tacs) for my successful cessation.

By November '12, there were days I used only 1 or 2 Mini's. My RLS episodes became nightly, sometimes daily, events. I happened to use a "Mini" for a tobacco yen while simultaneously experiencing an episode of RLS. The "Mini" stopped the RLS within 3-4 minutes.

I continue to use the "Mini" daily for RLS. I wonder if nicotine addiction predisposes a person to RLS and is RLS a withdrawal symptom from the addiction...

Carol C.

PEOPLE'S PHARMACY RESPONSE: Your approach is probably pretty unusual, but not quite unique. A case report was published in 2010 in which smoking alleviated RLS.
Nicotine gum seems safer.

Thank you so much for this article. (did not know you had developed soap chips). I had read of soap working for years and simply could not believe it. However, having recently starting to have severe leg cramps at night, I bought some new soap. It wasn't cramps that showed up however, it was my left foot jerking off and on, tremendously annoying. I took a new bar of soap, never dreaming it would work for me, put it in a sock and put the sock on and all jerking stopped!

Except then my right foot began to do the same thing. I did the same thing, and instantly the jerking stopped. I simply could not believe it. So glad to read of some science behind this. I was so afraid it was simply the placebo affect and it would not work on me. Many thanks again.

I was wondering how to deal with a long airplane flight. My legs get very sore when I have to sit for a long time. How can I use the soap for that. I just discovered this forum a couple of nights ago when
I couldn't sleep, I tried the soap last night and it did work for me. LL

I have gone one step farther on the soap under the sheets. I wet the soap and apply to the calf of my legs. The pain and/or leg cramps are gone within 10 to 15 minutes most of the time. Yes, the soap works. I have tried a number of brands, and they all seem to work.

Hard to believe but I had some little bars of soap from hotels so I gathered them all up and piled them under the sheet. The gabapentin for RLS lasts 2 hours for me - but the soap lasted all night as my legs snuggled up to them and slept 'til 7 AM. I have a new lease on life!

I have horrible lay on the couch with a heating bad on my lower abdomen and lower back pain killer kind of cramps monthly. Can some one tell me how to use the soap for my cramps? I use them for my leg cramps at night. I need some help with my menstrual cramps though. Thanks!

I have been suffering from such severe leg and feet cramps for this past year that were so bad they would cause me to limp half of the day as it felt like my muscles were torn. I tried all the normal things and nothing worked. An old friend of mine told me she heard that if you tossed a bar of soap in your bed that might help. So I did... wrapper and all. I just tossed it on top of the top sheet a week ago and 7 days have gone by now with not one cramp!!! I am not a believer of "wives tales" so just now googled this to see if I could explain why I have now proven it works! I get giggles from everyone I tell this last week and still can't believe it's working myself but 7 days of no leg or feet cramps proves it to me!

Out of these 7 cramp-free days, I would have had cramps in my legs and/or feet at least 5 of them. This bar of soap was what I had on hand, Coast, and it just lays wherever in my bed, I don't necessary lay on it, it's just in the bed when I crawl in. I'm going to stick with buying Coast since that's doing the trick!

I am an elderly woman who has had leg cramps for years. Not much help, chemicals don't help. A friend told me of soap in your bed and no more night cramps. Such a relief--it works. I've told many friends, and their results are very positive..

I had severe leg cramps since childhood. I am now in my 80's and only recently in a chance conversation with a Canadian friend was told about the soap treatment. I could not believe how immediate the relief was that very night. I have been telling groups and individuals about it since. Incidentally, it must be the vapor theory since I do not unwrap the bar of soap.

I have had 90 hours of training in aromatherapy at an accredited community college. Here is a suggestion for the mechanism of the soap effect. The olfactory nerve is the only nerve in the body which has a direct connection to the brain. It is so sensitive, and unfortunately, most of us are not even aware of the effects that volatile molecules have on our bodies via that nerve. There is plenty of literature that discusses this mechanism.

I don't know how to find my original post here, but since that day I posted I've had no leg cramps until a few days ago, so replaced my bar of soap in my bed and voila. Guessing it's been about two months or so, but just letting you know it sure works for a long time, then guess we have to change the bar lol! I was using a full size bar of Zest that was in a wrapper. I purchased a 6 pack of Zest and dang, they were in boxes so I removed the bar I'd been using and replaced it so I'd not have to have a hard box in my bed. :)

Just tried this three nights ago. Bear in mind that placebos and "alternate therapies" have never worked on me no matter how much I wanted them to. I have a B.Sci. and am quite the skeptic, but my RLS had gotten so bad of late I would sleep with a giraffe if it gave me relief.

Three nights in a row, has worked like a charm, including waking up with the start of RLS, thinking "Hhnnn where is my soap?" fishing around for it with me feet, tucking it between my ankles and feeling the RLS just stop dead.

I used unscented soap and it worked! So it's not the scent.

I don't know why this works but I DO KNOW that it does! ! I've been suffering from bad leg cramps at night for 6 months. I tried the bar soap theory skeptical at first, My leg cramps were gone. I went to stay at granddaughter's in Arizona, the cramps came back. I had to go to store in morning for a bar of soap never got the cramps again while I was visiting. I am convinced whatever reason being it works.

Ibuprofen is the key! It works wonders on menstrual cramps. I take 3 every 6 hours during painful periods.

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