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

October 27 2016 by in Ketosis, Potential LCHF problems

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 rash“¹ – 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

Sweat While there are dozens of theories about this problem, each more weird and unlikely than the next, we 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:

Clothing: Wear comfortable clothing for the climate, so that you don’t sweat more than necessary. Use air conditioning when appropriate.
Shower: After exercising it might help to take a shower – after you’re finished sweating.
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.
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.
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 We 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.

Comments

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

Potential other side effects on low carb

Reduced physical performance

Reduced tolerance to alcohol

Elevated cholesterol

Potential danger when breastfeeding

Gallstone problems

Temporary hair loss

Low-carb myths

Does the brain require carbs?

A ketogenic diet for beginners

14-day keto diet meal plan with recipes and shopping lists

Keto Q&A

There are many common questions about keto, and we do our best to answer them all. Feel free to check out our full keto FAQ, or choose one of the questions below:

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

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321 comments

301
Ruth Maher-Heslip
September 7 2020
I’m on Day 7 and a rash has appeared identical on both sides underneath both breaths. Feel great apart from this, it’s only mildly itchy at the moment but I do quite high intensity excercise so think this may helped the rash along. Could I be in Ketosis after just 7 days?? I’ve been strict but I expected it to take longer...hopefully the rash doesn’t get worse!! Glad I found a reason for it quickly as I was worried it was something like shingles

Reply: #302
302
Reply to comment #301 by Ruth Maher-Heslip
Crystal Pullen Team Diet Doctor
September 8 2020

I’m on Day 7 and a rash has appeared identical on both sides underneath both breaths. Feel great apart from this, it’s only mildly itchy at the moment but I do quite high intensity excercise so think this may helped the rash along. Could I be in Ketosis after just 7 days?? I’ve been strict but I expected it to take longer...hopefully the rash doesn’t get worse!! Glad I found a reason for it quickly as I was worried it was something like shingles

The amount of time ketosis takes varies from person to person. Showering as soon as possible after your workout may help.

Reply: #303
303
Reply to comment #302 by Crystal Pullen
Lissa
September 14 2020
I have done the medical weight loss keto diet once and never had issues with a rash. I’m wondering if how I started it this time could be why I developed a large rash on both inner forearms, under upper arms, neck, chest and parts of my upper front thighs. I originally thought it contributed to severe stress I was under at work. During riots and protests our building was surrounded and for one week everyone was scared when leaving and evening the building and then to deal with vile verbal abuse from all over the world. I went to my PCP and she gave me prednisone and hydroxyzine which seemed to have helped a lot over the last 4 days. Although, now that I think about it. I started using Pruivit ketones. It’s a challenge where you drink straight ketones to get you into ketosis quicker. I drank it the week before the chaos at work began and stopped abruptly when focus went off food and drink to work work work. Anyone try pruivit?
304
Shirlee Willis
October 3 2020
I have had terrible itchy skin for weeks now. I’ve been on Keto diet since June first and have lost 16 lbs. My rash looks like bites.. theyIt’s so bad I bleed. They are now head to toe literally- in my hair down my back arms, legs and on top of my feet. Itching is worse at night and where I lay. Can’t sleep. My dermatologist is baffled.. I’m going to share this with him. Doctors need to know about this.
I am going to increase my carb intake and hope it helps. Still No sugar! Thanks for all your comments I’m game to try anything at this point.

Reply: #305
305
Reply to comment #304 by Shirlee Willis
Kerry Merritt Team Diet Doctor
October 3 2020

I have had terrible itchy skin for weeks now. I’ve been on Keto diet since June first and have lost 16 lbs. My rash looks like bites.. theyIt’s so bad I bleed. They are now head to toe literally- in my hair down my back arms, legs and on top of my feet. Itching is worse at night and where I lay. Can’t sleep. My dermatologist is baffled.. I’m going to share this with him. Doctors need to know about this.
I am going to increase my carb intake and hope it helps. Still No sugar! Thanks for all your comments I’m game to try anything at this point.

Best wishes to you, Shirlee! We hope our tips will be helpful for you!
306
Brisa
October 4 2020
I was 6 months into keto dieting when I had 3 cheat days in a row. After that, a rash started under both of my underarms. I had just swithch the deodorant and tought that that was the reason, but I went back to my old one and that did not work. It has been a month or so and the rash is still there. I have big red patches that each ans hurt. I have not figured out when they get worse. I have noticed that my scalp itches, my legs ans face each too. I only feel little bumps on my legs but notting as my underarms. I have only applyed coconut oil and it helps a little with tje itch. I will try vinager, quercetin and see what happens.
307
Nel Acob
October 5 2020
When I started keto it took about 3 weeks for rash to appear. It was horrible, itchy and kept me up at night. I tried all suggestions you can find - blackseed oil, bile salt, baking soda, coconut oil but found no relief. I resorted to increasing my carb to 30-40g a day and that seemed to do the trick. Its beenabout 6 weeks since I started ketogenic diet and anytime I drop lower than 20g carbs a day, they start to reappear. I’ve been testing with keto mojo so I know I’ve stayed in ketosis the whole time. I just need to make sure I find that sweet spot or the plague comes back. I also found that somehow they are triggered during my cycle. Not sure if that’s just a coincidence but found another article that proves there’s a correlation. I don’t ever want to stop this lifestyle but it’s definitely adding another layer of frustration when I have to deal with this rash throughout my journey. Would appreciate any other suggestion..

Reply: #308
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Reply to comment #307 by Nel Acob
Crystal Pullen Team Diet Doctor
October 5 2020

When I started keto it took about 3 weeks for rash to appear. It was horrible, itchy and kept me up at night. I tried all suggestions you can find - blackseed oil, bile salt, baking soda, coconut oil but found no relief. I resorted to increasing my carb to 30-40g a day and that seemed to do the trick. Its beenabout 6 weeks since I started ketogenic diet and anytime I drop lower than 20g carbs a day, they start to reappear. I’ve been testing with keto mojo so I know I’ve stayed in ketosis the whole time. I just need to make sure I find that sweet spot or the plague comes back. I also found that somehow they are triggered during my cycle. Not sure if that’s just a coincidence but found another article that proves there’s a correlation. I don’t ever want to stop this lifestyle but it’s definitely adding another layer of frustration when I have to deal with this rash throughout my journey. Would appreciate any other suggestion..

I am sorry you continue to suffer from this. The Diet Doctor suggestions are included in the article under "How to cure the keto rash".
309
Kat
October 21 2020
Thanks for the info.i have the rash on my back and I’m not even on Keto diet. I eat less for the past week and removed sugar and dairy in my diet. Would this be a Keto rash?

Reply: #310
310
Reply to comment #309 by Kat
Kristin Parker Team Diet Doctor
October 21 2020

Thanks for the info.i have the rash on my back and I’m not even on Keto diet. I eat less for the past week and removed sugar and dairy in my diet. Would this be a Keto rash?

If you are not eating keto and not in ketosis then it's not likely to be keto rash. If it doesn't resolve soon, please check in with your doctor.
311
Maggy Holt
October 22 2020
Been on the keto diet since August 20th so just over 8 weeks ..... I had this rash that was itchy and driving me crazy, I thought it was my fabric softener at first until I stumbled upon this web page ..... since reading all the posts I decided to take some black seed oil orally, 1 TSP daily for a few days then increased it to 2, luckily the itch scratch rash begun to ease ..... This Sunday I will be increasing my carbs to between 50 -100 as my body may need a bit of a boost to help the situation, I've been very strict at the beginning of the diet sticking to 10 net carbs for most days with the odd few times increasing to 20, I've managed to lose 20 lbs so far but need to double that figure ..... I can achieve my goal but only with this KETO DIET it's working so well for me, this Rash will not stop me
312
M
October 25 2020
Many keto foods are high in histamine, so the keto rash is most likely due to high histamine levels. Find lists of high histamine foods and low histamine foods. Avoid/minimize high histamine foods and eat more low histamine foods. It works.
313
Laurie
December 11 2020
Have reversed my T2 and lost 50lbs on keto -been in ketosis for past 18 months and itching intensely for about 9 months now. It is dreadful and keeps me awake, and no cream helps at all. Might experiment with low histamine foods before coming out of ketosis........
314
Jane
January 18
I have been doing keto for 2 weeks and have an itchy rash appear on my chest. It’s not overly bad but quite itchy and doesn’t look very nice. I’m at 18g net carbs per day. What should I up my carbs to?

Reply: #315
315
Reply to comment #314 by Jane
Kristin Parker Team Diet Doctor
January 19

I have been doing keto for 2 weeks and have an itchy rash appear on my chest. It’s not overly bad but quite itchy and doesn’t look very nice. I’m at 18g net carbs per day. What should I up my carbs to?

This is from the guide above:
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.
316
Katie Cumberlin
February 13
Within 4 days of me following keto I've developed the rash 3 times. It's in my chest, underarms and this time also on the back of my shoulders. I'm hoping increasing my water intake and taking supplements will help so I can continue following keto. As soon as I increase carbs again the rash disappears. Very annoying when you're trying to lose weight and keto works for you!
317
Ariel
February 21
I have been on keto for about a month. My rash began after a week in. I had also just began a new medication so I thought that was the culprit. I stopped medication for 5 days, no change in the rash. It appears like clockwork every night on my face, neck, arms, back. It is driving me insane! It's like I am covered in mosquito bites every night. I am hesitant to add carbs, I have been doing so good on this diet and am down 12 lbs in about 3 weeks. Ugh!

Reply: #325
318
Jasmine
February 22
Similarly I got keto rash after 6weeks, it was extreme with blisters on my back and chest. It was worse with heat and sweat. I couldnt sleep from the pain and agony. I'd never heared of keto rash before. I went to my doc who prescribed me with antifungal and antibiotics. Then swabs done which shown no fungal. Meds didn't help. I searched on Google and found out about keto rash. I introduced carbs back and was getting better a few days later. I decided to try keto again. However rash came back.
319
Scott
March 23
I started a Keto diet and within 3-4 weeks was seeing the benefits of feeling more energetic and weight loss of about 20lbs. Then the Keto rash hit. To make matters worse, I have had dermatographism for about 15 years. It has been controlled up until I achieved ketosis. The resulting skin irritation can only be described as hell. So I slipped out of ketosis to a low carb diet and increased the meds that had controlled my dermatographism. Now I have the rash under control and I'm planning to get back into ketosis. Looking forward to the perks of the keto diet again...
320
Michael C
March 25
@Greg .. thanks for the tip about SciZenna, in the past I have always used regular Black Seed Oil and it works to relieve and resolve my Keto rash, but very hard on my clothes. I just ordered some SciZenna cream and hope it will be just as effective without getting oil on my clothes.
321
Meta Fahrenfort
March 29
I live in the tropics and have been eating a ketogenic diet for years now. I experience keto rash as soon as I neglect taking in salt and water - as is recommended in the tips for keto flu. I think that is because naturally I lose salt through perspiration and my body needs salt to maintain a good urine production - if my body restricts that, the ketone body concentration in my blood goes up and I get itchy.
I have been missing this 'water and electrolytes management' tip everywhere where keto rash is discussed.
Treatment: I found that whenever the patches get too bad I can very effectively treat them with 10% salicilyc acid (onguent made by my pharmacy). Cheap and 100% effective but to be used on small areas.
322
Amy
April 1
I'm so happy I found this page, I could cry. Had the rash 3 times in the past year and a half, and as one other commenter mentioned, it seems to correlate with my cycle. Not sure why, will do more investigation. Dermatologist was perplexed, never seen anything like it.
I thought it was contact dermatitis but it's the SAME pattern each time, which negates that. Upping carbs and salt water consumption def helps. THANK YOU to this website for the info and the sanity!!
323
Lorinda
April 3
Keto rash is usually on the torso, but I can never do things in a normal fashion. I read that it (rarely) could be on the extremities, and I have it on my toes. Just got back from the dermatologist after two different doctors threw their hands up in the air, baffled. There is the possibility that it could be "Covid Toe", but unlikely. This started 2 weeks after I began keto. Horrible, itchy blisters on the tips of my toes, and some in between. Prescription lotions didn't help at all. The dermatologist wants me to add some carbs and take strong antihistamines to try to get rid of it. I hate to go out of ketosis, but low carb might have to be the new way of eating for me.
324
Erna Pashley
April 3
Good morning.....I’ve been on Keto for 2.5 months and am feeling on top of the world. Just loving it.
I’ve read Shirlee Willis post #304 and can relate 100%. My itching started way before I started Keto, but not sure if Keto is contributing to my uncontrollable itching at night time.
I’ve been on every steroid, tablet, cream, antibiotics and antihistamine over the last 5 months.
Mine is on my legs, feet, earlobes and lower back, so not your typical Keto torso rash.
I’m going to see a Dermatologist on the 9th of April.
I was just wondering what your Dermatologist said Shirlee, as it will be a big help.
Many thanks for any feedback.
325
Reply to comment #317 by Ariel
Kristi
May 23
That doesn’t sound like keto rash. It doesn’t go away and come back. It comes and typically stays. And it’s VERY red and fades slowly. At least that’s my experience and I have had it multiple times. Currently have it and love it because it confirms something is exiting my body that needed to. I actually suspect it’s a detox reaction related to bad bacteria in the gut losing their food source (sugar) and exiting the body through the skin.

Replies: #326, #327
326
Reply to comment #325 by Kristi
Kristi
May 23
Oops. I said bacteria. I actually meant Candida overgrowth.
327
Reply to comment #325 by Kristi
Crystal Pullen Team Diet Doctor
May 24

That doesn’t sound like keto rash. It doesn’t go away and come back. It comes and typically stays. And it’s VERY red and fades slowly. At least that’s my experience and I have had it multiple times. Currently have it and love it because it confirms something is exiting my body that needed to. I actually suspect it’s a detox reaction related to bad bacteria in the gut losing their food source (sugar) and exiting the body through the skin.

A facial rash would certainly be a reason to visit with your medical professional.
328
Nancy
June 7
I've tried keto many times and time after time I quit due to the terrible itching.

What Significantly cured it: PICKLE JUICE
329
Max
June 29
Doctors are so clueless. I've been in ketosis for about 4 years and when I started OMAD, my rash started. I sent pictures to my doctor who knew I was in ketosis and he said it was probably a fungal infection and take anti-fungals. They seemed to help a little bit, but the problem never went away. I kept using antifungals because they helped a small amount. When performed research on my own and learned about keto rash, I added fruit to my diet and stopped OMAD. This provided instant relief. It's too bad that my doctor was so clueless and caused me to suffer for several months.
330
Sara H
July 15
Where do I even start. The rashes on my body is exactly like the image above. All over my chest, my lower back and bikini area. It’s my first time doing Keto. Day by day it’s getting worse, spreading in other areas. Like it creeped up slowly on my chest area and the next day when I woke up it started to cover up my breasts. Going to add carbs. No more keto, not worth the pain.
331
David
3 days ago
Wife and I are in keto and we had rash. Took Allegra thinking we developed a food allergy. Gone. No rash. Take it daily and we’re good. If we forget the Allegra, rash reappears.