Blog Categories


Keto Rash: Causes, Symptoms, Treatment, and Prevention


There are many reasons people choose to go on the keto diet. Whether it’s weight loss, reducing inflammation, or improving overall brain health, research shows that keto can help many individuals. However, certain side effects can come with a change in your diet. One unusual sign that can appear is a skin rash called keto rash.

What is Keto Rash?

Keto rash is an inflammatory, uncomfortable skin condition that can appear in people who have just started following the keto diet. According to the American Academy of Dermatology, it’s also called “prurigo pigmentosa” and occurs mostly in young adult women (*).

This rash triggers red, raised papules across the upper shoulders, back, and abdomen. There are similar characteristics between keto rash and other skin conditions (such as eczema), but the keto rash is distinctive in its network-like pattern of spots.

The keto diet rash is rare, and researchers have not yet fully understood its causes. It is, however, associated with being in a state of ketosis, wherein the body burns fat for energy instead of using carbohydrates.

Uncontrolled diabetes and anorexia nervosa may also be associated with the keto rash — although keep in mind that the keto diet in and of itself does not cause diabetes and anorexia nervosa, and may even help address them.

Furthermore, keto rashes may be triggered by certain factors, such as friction from one’s clothing and sunlight, among others (*). Some people are also more likely to develop the rash than others, particularly people of Asian descent (*).

Keto Rash Symptoms

There are several distinct symptoms that characterize keto rashes. These include the following:

  • The appearance of red raised papules on the skin
  • Common areas affected include the chest, upper back, and neck
  • The rashes appear symmetrical and web-like
  • Feeling of itchiness
  • Over time, the rash leaves a brownish discoloration of the skin after the inflammation has resolved

What Does Keto Rash Look Like?

Keto rash appears as red and raised papules that affect the neck, upper chest, and back areas. Here are some keto rash pictures:

Keto Rash:
Image source: NCBI

Causes of Keto Rash

The exact cause of the keto rash is unknown, although a link has been found between ketosis and the condition (*). However, several potential triggers can lead to the rash in individuals following the keto diet:

  • Drastically reducing your carb intake. Reducing carb intake can lead to weight loss, which is a welcome side-effect of the ketogenic diet. However, doing it too quickly may lead to the development of the keto diet rash (*).
  • Excessive fasting. When blood sugar levels are low due to fasting, ketosis can start. However, this can also contribute to the development of the keto rash. Case in point, 8 out of 16 participants in a study who fasted developed prurigo pigmentosa (*).
  • Ketones. The keto diet involves entering a state of ketosis, during which the body uses fat for energy instead of carbohydrates. During ketosis, the body produces ketones that may cause inflammation around blood vessels, resulting in skin rashes (*).
  • Allergens. Consuming keto-friendly foods that contain allergens may trigger keto rashes. Examples of these allergens include eggs (both egg yolks and egg whites), dairy (due to milk proteins), and seafood (e.g. shellfish and scaly fish).
  • Skin irritants. Some external skin irritants, such as chlorinated pool water, friction from clothing, and sunlight may trigger the keto rash.

Keto Rash Treatment

Keto rash can be uncomfortable and frustrating to have. Fortunately, there are several ways to treat the condition:

  • Wait for the keto rash to subside. In some cases, a keto rash may be resolved on its own by simply waiting for the symptoms to subside. While the rash may disappear on its own, it is important to consider other treatment options (by first paying a visit to the doctor) if it persists after a week or two.
  • Reduce your intake of foods that trigger inflammation. Keto-friendly foods are good for you; however, you still need to be careful of certain foods that contain allergens, which lead to inflammation. Minimize your intake of known allergens, such as milk (both dairy and nut milk), eggs, fish, and scaly fish (*). There is no need to eliminate them unless you already have the keto rash.
  • Consume enough nutrients. Nutrient deficiencies can greatly affect your skin health. When starting the keto diet, it is crucial to ensure that you are consuming enough essential nutrients. Chronic skin conditions can occur more easily if the body is lacking in vital micronutrients, such as vitamins A, B-12, and C. Dietary modifications that address any nutritional deficiencies have been shown to prevent the recurrence of many skin conditions, including the keto rash (*).
  • Consider using supplements. If getting enough nutrient-dense keto foods is difficult, then taking multivitamins and other supplements may help. Many people on keto may need to supplement with nutrients such as vitamins, minerals, and electrolytes. Getting enough sodium, potassium, and magnesium, for example, can sustain multiple vital metabolic functions.
  • Consider adding back carbs. Unfortunately, for some keto dieters, the keto rash persists and negatively affects their daily activities. If ketone production is the cause of the rash, then modifying your diet by increasing carbohydrate intake can be one way to counteract it (*). Going out of ketosis for a few days to see if the rash improves may be necessary in this case.
  • Follow skincare tips. This includes daily habits like washing your skin with mild and gentle soap, not scratching the area, and applying a moisturizer that helps relieve the discomfort.

How to Prevent Keto Rash

Developing keto rash is uncommon, but you can prevent it by starting the keto diet with some precautions:

  • When lowering carbohydrate intake as you start the keto diet, do it slowly and gradually. Avoid dropping your carb intake suddenly as this can cause unwanted side-effects such as the keto rash. Instead, try to slowly taper carbohydrates out of your diet.
  • Drink vitamins and supplements even before starting the keto diet. This will prevent the development of any nutrient deficiencies that may cause or exacerbate the keto rash.
  • Pay close attention to any rash signs. Increase your carbohydrate intake for a few days until the rash starts to subside.
  • Given that excessive fasting may potentially lead to keto rashes, it might be a good idea to start with a shorter fast (such as a 13-hour or 16-hour fast) and avoid long durations. Note for any skin reaction.

Frequently Asked Questions

Here are some commonly asked questions about the keto rash:

How long does keto rash last?

Keto rash can last up to two weeks. If you have developed red, itchy papules on your neck, chest, and back that have persisted for a few days to a week or more, then it’s time to seek treatment.

Does everyone get the keto rash?

Only some people get the keto rash, as it is pretty rare. Still, taking precautionary measures when starting the keto diet is the best approach for preventing keto rashes from occurring.

Is keto rash contagious?

No, a keto rash is not contagious, nor is it dangerous. The best way to treat it (besides waiting for symptoms to subside) is to ensure you get enough vitamins and minerals while avoiding common food allergies. If these methods don’t help, then upping your carb intake temporarily or talking to your physician about anti-inflammatory medications can help.

My keto rash isn’t going away. What should I do?

If the above tips on treatment and prevention don’t clear your keto rash, then it may be time to talk to your physician. Some medications, such as antibiotics, may be effective at treating keto rash symptoms. However, do note that antibiotics should be the last resort as they come with side effects. This is also important to prevent antibiotic resistance.

What part of the body does the keto rash usually appear on?

The keto rash typically appears on various areas of the upper torso. You may notice red, itchy bumps on your neck, upper back, chest, and abdomen.

The Bottom Line

The keto rash may sound alarming, but remember that it is rare. As with any new diet, it helps to take precautions and ease into keto slowly. Taking preventive measures can prepare your body to handle ketosis with minimal side effects.

Even if the rash does appear, following the above mentioned tips can help with relieving the condition until it completely disappears. The risk of developing a keto rash is low, so don’t let it discourage you from trying the keto diet, especially if it can help you lose excess weight and improve your metabolic health markers.

11 References

Warren R Prurigi Pigmmentosa As The “Keto Rash”: I’M A BELIEVER. 2020 February 5

Warren R Prurigi Pigmmentosa As The “Keto Rash”: I’M A BELIEVER. 2020 February 5

Asfandyar M et al. Clinical manifestations and treatment outcomes in prurigo pigmentosa (Nagashima disease): A systematic review of the literature. 2021 April 10

Anny X et al. Ketogenic Diet-induced Prurigo Pigmentosa (the “Keto Rash”): A Case Report and Literature Review. 2021 December

Felix A et al. Keto rash following carbohydrate restriction. 2022 May 4

Y J Oh et al. Prurigo pigmentosa: a clinicopathologic study of 16 cases. 2011 September 20

Mustafa A et al. Prurigo Pigmentosa After Bariatric Surgery. 2015

Food Allergies. 2023 November 01

Basavara K et al. Diet in Dermatology: Present Perspectives

Miki W et al. Treatment of Prurigo Pigmentosa with Diet Modification: A Medical Case Study. 2018 May


Join the Internet's largest keto newsletter

We'll send you articles, product guides, and exclusive offers customized to your goals.