Keto rash – Why some people itch on low carb, and what to do about it

Keto Rash

Typical locations of a keto rash

This is not a common problem on low carb or keto, but for the few people experiencing it, it can be really annoying: Itching.

This itching – sometimes called the “keto rash1 – can be troublesome, sometimes even interrupting sleep. The itching and rash are almost always symmetrical on both sides of the body. It most often develops over the chest, back, armpits and sometimes in the neck (see image above).

What is the reason for this problem, and how can it be cured?

There are many posts about this online, and many different theories. The time has come to make it simple, Diet Doctor style. Here’s everything you need to know.


The cause of the keto rash

SweatWhile there are dozens of theories about this problem, each more weird and unlikely than the next, I believe there’s a very simple answer. This is based on many people’s experiences,2 and the limited scientific studies available.3

Here are the clues, and the conclusion:

  • The itching usually starts soon after people get into ketosis. It stops within a day or so if people eat more carbs and exit ketosis.
  • It can often get worse in hot weather, or after exercising.
  • The usual distribution of the itch and rash matches areas where sweat can accumulate.
  • When in ketosis sweat can contain the ketone body acetone.
  • Acetone can be irritating at high concentrations.

I think there is good reason to believe that the itching that some people experience in ketosis is caused by ketones in sweat, perhaps as this dries on the body.



How to cure the keto rash

There are several things you can do to cure keto rash:

  1. Clothing: Wear comfortable clothing for the climate, so that you don’t sweat more than necessary. Use air conditioning when appropriate.
  2. Shower: After exercising it might help to take a shower – after you’re finished sweating.
  3. Change exercise plans: If the itching is really troubling you might want to skip exercise for a few days, or do something like brief weight training that does not produce perspiration.
  4. Exit ketosis: If the the steps above are not effective enough, exiting ketosis will reliably cure the issue within a day or two. This can be done by eating about 50 grams of carbs or more every day. To still get most of the benefits of a keto diet – at least for weight loss and type 2 diabetes reversal – you can do a more liberal low-carb diet (50-100 grams of carbs per day) and add intermittent fasting.
  5. Other treatments: There are many other treatments suggested online; like antibiotics taken for weeks or months and/or special creams. These will likely offer temporary relief at best.4 I definitely advise not to use oral antibiotics, as the side effects and risks are much worse than the doubtful and temporary benefits. Steroids, anti-fungal creams and anti-histamines appear not to be effective at all. There’s a safe, simple and free solution if you need it – number four, above. Use that instead.



What’s next?

If you get rid of the keto rash by exiting ketosis, can you ever use ketosis again? The answer is likely yes.

If you felt great in ketosis and had a lot of benefits, you may want to try again. The keto rash may stay away. Some people appear to get it only once, or only early in ketosis, when first starting out on a low-carb diet (given time, the body may excrete fewer ketones in the sweat). Remember, most people in ketosis don’t get the rash at all.

Keep the advice above in mind. And if all else fails, just eat a bit more carbs and the problem will go away.


Have you experienced keto rash? Do you want to share what helped and what did not? Feel free to leave a comment below!



  1. Another name that is sometimes used for this condition is “Prurigo pigmentosa“.

    The name means that it itches (“prurigo”), and that long-term, after many weeks, it can result in increased pigmentation (“pigmentosa”) in the affected skin area, looking like darker patches.

    This increased pigmentation, should it occur, fades very slowly after the rash is cured.

  2. Here are a few places to read about people’s experiences with keto rash:

  3. Here are a few relevant studies:

  4. This study references the experience of treating the keto rash (prurigo pigmentosa) with antibiotics. It did have an effect – possibly due to anti-inflammatory properties – but once the treatment was stopped the rash reappeared.

    J Dermatol. 2012: Prurigo pigmentosa: clinicopathological study and analysis of 50 cases in Korea.


Top comment

  1. Justin
    Good to finally see *something* written about this. I remember being unable to find anything when it happened to me in 2014. Read a lot about skin conditions, tried various antifungal creams, coconut and tea tea oil. Eventually had to admit the obvious source, my recent change to a ketogenic diet. I had the itch under my armpits and abdomen. It was intense. Not "troublesome". And it receded almost as soon as I began eating carbs. I only managed 7-8 weeks in a ketogenic state before I couldn't take the itching any more.

    It was too bad as I really enjoyed the ketogenic diet, felt less drowsy, and much better GI function (less gas, cramps, diahrea). Also was forced to eat more vegetables and nutritionally rich foods.

    Interesting idea that it could be related to acetone/ketone presence in sweat. I had figured it was related to the affect low blood sugar has on the adrenal gland, and how long term elevated cortisol might disrupt the immune system. The rash being some adverse inflammation as it's very similar to hives.

    I would love to see some proper research done on this. Heck, I would love to be the one doing it.

    Excellent article. Thank you.

    Read more →
1 2 3 4

All comments

  1. Paula
    I just received the Swanson Bile Salt 100mg tablets. What is the dosage I should take to get rid of the rash? The bottle says to take one a day. I have seen other people saying to take one with each meal if you had your gallbladder removed (I still have my gallbladder). Also, do you take one on fasting days? I know that IF can make the rash worse but should you take on a empty stomach?
  2. Kel
    Epson salt baths high concentration and frequent I’ve had it twice. Walmart has 3 lb bags for under $6. Ginger and clay seems best for me. Use about half the bag or more. Cortisone (think it’s called) Cream from the pharmacy helps locally. Also consuming carbs works. Good luck!! It’s a sure sign you’re in ketosis however :)
  3. Sara
    I have had it multiple times. Under breasts and solar plexus area. I do not have overly sensitive skin. Seems to be triggered by sweat/exercise for me, as well as when I am trying to be more strict on my carbs (under 20 net), it will flare up. What has worked for me: 1. Raw APPLE CIDER VINEGAR - keep it in the fridge and apply liberally to rash. Immediate relief - apply several times a day and rash goes away. 2. I used my dog’s “vets best hot spot shampoo”. It is all natural and contains tea tree, eucalyptus among other things. Desperate times desperate measures. Used it as body wash in shower, ***lather over rash area and leave it sit for a couple minutes*** rinse off. This really works well, does not sting and I recommend it. Available online or specialty pet stores. Green bottle.

    Then before bed swipe the area with ACV. The combined use of these two things has helped me immensely.

    Lastly, when I work out, I keep a pack of wet wipes in my car / gym bag so the moment I leave workout class, I can do a quick wipe to remove the sweat from the areas most affected to get the acetone off my skin before it dries.

    Hope this helps someone!!

  4. kari
    OMG, I'm glad I'm not alone or going crazy. And of course thought the worst, kidney failure.... I'm 3 weeks in, 17 lbs gone, no viable rash, just itching on my stomach and breasts like mad!!
  5. Monika
    After a very serious Keto-rash, which Dr treated with antibiotics. That just triggered an allergic response. Really scary episode.
    I finally had my DNA done. 23and me. This showed that my livers process1 st phase was very fast, however the 2nd phase of elimination was really, really slow. So released toxins were just recirculated.
    That makes a lot of sense to me- could also explain unexplained allergies.
  6. Lumka
    I suddenly had a reaction to prawns and fish that I’ve never had before. Throat so sore I can’t even eat or swallow. Itchy and joints and ever single part of my body is in pain I can’t even bend my fingers or walk. The sudden rash is unbearable itching will start on my head then all over. I had the exact same fish last week but suddenly I can’t even touch it
    Reply: #177
  7. Lizelle
    I experienced keto rash due to not knowing that i had inflamation in my body before I started keto.

    Once the inflamation was solved the rash gradually dissapeared. I used lots of water & green tea to flush it out of my system as i can’t take anti-inflamatories, plus alovera gel helped me through the worst stages until my liver adjusted. Dr Eric Berg has a few youtube videos on this topic which was very helpful.

  8. Tina
    What is the medicine for keto rash?
  9. 2 comments removed
  10. Angella
    Aaaaaah for a solid week I've been homeoing. ACV, cold compresses, ice, sulfur, calandula, rhux, calamine, tec-nu. And asking everyone and their mother!!!
    Thought it was poison : ivy, oak or sumac, as I just moved up into the mountains with my dogs into a cabin😬. Consequently I started Keto at the same time! I wait tables, sweat a lot at work AND have been quite full of stress lately. Sooooooo..... is it shingles's? Is it poison ivy? Is it an allergic reaction to laundry detergent? (Which has happened) OR ???????
    Omg! Pretty sure it's KETO!!!☹️☹️☹️ Very NOT happy bout this... since I've been seeing results and feeling better. But my lower back and bum crack looks like I'm morphing into a dragon 🐲. Which would be really cool if I could eventually breath fire. Not likely.
    Oddly enough after all the remedies most of the blisters and itching has subsided. But the rash has not started to shrink. It's actually spread just a tiny bit around to the sides of my waist😔.
    So carbs here we come😜☹️
    Reply: #164
  11. Amy
    I’ve had this rash for about four months. Mine isn’t super itchy though but it’s not getting any better. It’s not red and blistering, more like the symmetrical pictures you can google that show the chest, back and neck and just white patchy discoloration. Also, mine isn’t from being keto, it’s from intermittent fasting. Everything I’ve read says up your carbs, I have. I’m not even super strict fasting. I’d just like to know if it’ll go away and I’m just dextoxing. I mean I tried keto and fasting to HEAL my body!! And now I have yet another item to heal!!!
  12. Sabiya Taibali
    I too am really struggling with itching. This is my first time with keto.. after reading everyone’s comments to up the carb to 50g, what do you actually eat?
    Does it have to be fruits, bread, grains or pasta???
    I really need help?
  13. Angella
    Soooooo.... the rash started to get better.... but now is spreading again.
  14. Hans Johansson
    I got some Cortison-salve which temp. helped but the only reliable way for me to loose it is to just eat carbs once every 3rd weeks. I usually mange to enter ketosis after eating carbs withing 1 week now (keto-sticks that I pee on says so atleast). so by eating some carbs every 3rd week I manage to keep the rash at bay.
    Intermitted fasting brings you quickly into ketosis so I just keep doing IF and eat carbs from time to time. Feels great imo.
  15. Stan Mould
    When I first started keto in May 2017 I got a mild form of keto rash mainly on my shins and a bit on my forearms. Not a problem at the time.
    However, I went back to the UK for the month of July 2018 (I live abroad) and so went off keto (impossible to do in the UK when you don;t have access to a kitchen). When I got back early August, I went full keto pretty quick and WOW!!

    Within a week I was covered on my chest, waist and back with a rash, and also down my shins and tops of my feet but less severe there. It was moderately itchy but not excessively so but it looked really bad. I read this article and increased my carbs as suggested, and it was gone in a few days.

    Now I want to get back into keto but I think I will need to take it much more slowly than I did. I'm not worried about it, but it did look unsightly and really worried my wife.

  16. Monica
    I'm new, day 4 and started itching but no visible rash yet... I'm happy to know I'm in ketosis 😃😃😃

    But this itching better back off because I have a lot to lose and dont want to up the carbs 😩 (though I think if it becomes persistent, I'll up them slowly until I find a magic number - hopefully it wont be too much higher than the 20)

  17. George
    Mine is exactly like hives - they come and go on arms, legs and a few on torso but they come and go within 24 hours and new ones appear in different spots as old ones disappear. It started off with just itchy palms and progressed to big round welts whixhbthw foctir identified as hives and said it was due to allergies. I never had any known allergies. When I eat mandarins it improves within a day so I guess it must be Keto rash although it’s different from the typical pictures - anyone with the same ? I guess it’s option no 4 as per the article
  18. Sal
    I started lowering my carb intake 7 months ago to around 75 to 90 grams of carbs per day. I have lost 40 pounds and feel a lot better, but a month ago I started getting the rashes. At first I thought I had shingles, but my doctor said no and gave me some cortisone cream. The cream reduced the rash but it was still there, I now have blotches of rashes all over my torso and down my thighs. The doc gave me some antibiotics but its not working that great. I am glad to find out what is causing this rash as my doc never mentioned that my low carb diet was the cause. The problem I have is that I do not want to increase my carb intake to more than the 90 grams per day. I will try some of the treatments mentioned in these comments and see were it goes. It's great to finally be able to put a cause to my problem, thank you.
  19. Therese James
    Wow great to finally know what it is I thought I had been bitten by something! I have had this before and I saw my Dr who tried to tell me it was scabies ...I refuted that so he put me on oral steroids for a few days and it went after 2 tablets ! I now have the rash again after my second attempt at keto so glad to know what it is ...I’m not going to take the steroids again as they will effect my insulin and glucose levels ? will see if in time it just goes by itself . Last time it was in my upper belly this time it’s in the middle of my lower back . I also have cramps and constipation which I cure with magnesium.
  20. Edie
    No rash, but EXtreme itching, sometimes almost to point of drawing blood. Backs of hands and forearms, tops of feet, head.
    Wonderful to have an explanation!
  21. Judy
    No rash just itch. Back, hips, arm pits, under breasts. Driving me crazy. I started June 23 and now Sept. 11. Had this for a month. Driving me crazy. I need relief. Changed bath soap, eased up some, same laundry soap. What do I do. I live with a wooden back scratcher. Almost 40lbs gone. Not going to stop. Doing very low carb.
  22. Mary Ricketts
    I started the Reversing Diabetes version of keto which says to stay under 20 carbs a day, right after Labour Day. I had been on a diet holiday for most of the summer. I take the max doses of metformin and glyburide daily, no insulin. After 3 days I had such horrible diarrhea that I cut my meds doses in half. That fixed the diarrhea but next I woke up with intense itching of my hands and forearms. It has spread to the areas pictured in the diagram and to my legs as well. It seems to migrate; I will get my arms settled with lotion (solarcaine works the best) and my back starts up. My sleep is really disrupted. I also have purple blood blisters on both forearms. I am going to try the ACV on them. I am also going to restart the vitamins and supplements from the Ideal Protein program in case that will help. Other than this itch I am enjoying the diet.
  23. Tina
    I started the egg diet (high protein/ low carb) and 2 days later my back right shoulder starting itching non stop. Two days later I developed a rash between my breast and armpit. The next day it had spread to my back. It is very painful. I can't find anywhere where someone else has experienced pain with the rash so I'm afraid I may actually have shingles. Please someone, tell me you have had pain with it???
    Reply: #176
  24. D. H. Cano
    I have done all this before starting decades ago with Atkins, always lose weight successfully, and never had the rash response before. Now here it is in a very florid form, perfectly replicating your illustration, and driving me nuts, waking me up and all the rest. Seeing it as an indication that I am in ketosis, and losing a pound or more a week, I am reluctant to up the carbs, so am trying to live with it and hoping it will go away or at least diminish. Here are my observations:

    Less bad breath than before. Is this because my body is using sweat instead of breath to dispose of ketones this time around?

    Cleanliness helps! Shower every time you have a sweaty episode! I live in a subtropical climate, heat and moisture are a fact of life, so this means showering two or three times a day. Get that residue off your body! You will feel immediate relief, even if it is temporary.

    Make swimming your exercise. Great full-body workout, no sweat accumulating on your skin. Drop sweaty exercises for now.

    Carry wetwipes and deodorant in your shoulderbag. A wet washcloth in a baggy. Anything to provide for wiping down when you are out. Don't let a buildup accumulate on your skin.

    Watch your alcohol intake -- it doesn't take much to get your skin flushed and sweaty, which is exactly what you need to avoid.

    These measures are making the k-rash tolerable for me for now. They don't eliminate it. I am hoping that with time my body will make its adjustments. If not, I think I can deal with it long enough to get substantial benefits from the only type of diet that has always, reliably and not too uncomfortably, resulted in weight loss for me.

  25. BackToBasicsWithBridget
    Yes, mine is very painful!
  26. Mike
    weird, because my rash began to develop 5 days ago, the day after eating a fair amount of crabmeat, that i have eaten before with no issues. i had also exited ketosis two days prior to that (drank some heavy craft beers), and the alcohol was my first inclination. sure hope it isn't a food allergy, as those keto crabcakes i made a couple of times are dynamite!
  27. Carol
    My doctor gave me Mometaone Furoate Cream usp 0.1
    Works within a few days to get rid of rash. Talk to your doctor.
  28. Darlene
    I was SO HAPPY to read all the comments. I have been on Keto faithfully since the beginning of April and have lost 35 pounds. The last 6 weeks I have started to get an itch, gradually getting worse. (No rash) Horrid itch. Back, armpits, chest, groin and now UNBELIEVABLE itch on my front belly and between breasts and sides. (also some hives) I started searching and first found information on a bad liver disease. It was looking like that was what I had. Then I found this site and happy to read my exact issues by so many others. I have some tea tree shampoo with mint at home and immediately started using it and also ACV every couple hours. So I'm hopeful that I've found the problem and some ways to deal with it. I will advise my outcome.
    FYI... although I researched on the internet I would also consult my doctor.
1 2 3 4

Leave a reply

Reply to comment #0 by

Older posts