Table of ContentsView AllTable of ContentsPrurigo Pigmentosa and DietFoods To AvoidFoods To EatOther Treatment OptionsFrequently Asked Questions

Table of ContentsView All

View All

Table of Contents

Prurigo Pigmentosa and Diet

Foods To Avoid

Foods To Eat

Other Treatment Options

Frequently Asked Questions

Prurigo pigmentosa(PP), also calledNagashimadisease, is a rare chronic inflammatory skin condition that causes an itchy rash withvesicles(blisters).The blisters eventually develop into brown spots that appear in a net-like pattern.

PP rash often occurs on the trunk and neck, but it can appear anywhere, including the face and scalp. It is also associated with conditions that produceketosis(when your body uses stored fat rather than glucose for energy), including restricting food intake and diabetes.For this reason, healthcare providers sometimes refer to it as “keto rash.”

This article explains the link between prurigo pigmentosa and diet, which foods can help the condition, and which ones to avoid.

Lauri Patterson / Getty Images

Fried Foods

PP is sometimes referred to as a"keto rash"because it is linked with those on restrictive food diets, especially aketogenic diet. A ketogenic (keto) diet involves eating primarily fat-based foods and significantly restricting carbohydrates.This eating pattern creates a ketosis metabolic state (the body uses stored fat for energy).

Since the diet is effective for weight loss, people often follow it to lose or maintain weight. However, some people also use it to reduce the risk of obesity-related health risks, likediabetes,hypertension(high blood pressure), and heart disease.

Researchers believe this connection may have to do with thegut microbiome(the microorganisms in your digestive tract). Thus, an imbalance in the gut microbiome may impact a person’s immune response, leading to PP.

Other CausesIn addition to diet, prurigo pigmentosa has been linked to other conditions, including:SweatingAtopic dermatitis(eczema)DiabetesAnorexia(eating disorder)Rapid weight lossPregnancySjögren’s disease(an autoimmune disease that affects joints)Helicobacter pylori(H. pylori) infection (bacterial infection)

Other Causes

In addition to diet, prurigo pigmentosa has been linked to other conditions, including:SweatingAtopic dermatitis(eczema)DiabetesAnorexia(eating disorder)Rapid weight lossPregnancySjögren’s disease(an autoimmune disease that affects joints)Helicobacter pylori(H. pylori) infection (bacterial infection)

In addition to diet, prurigo pigmentosa has been linked to other conditions, including:

Foods to Avoid

If prurigo pigmentosa is associated with ketosis, your healthcare provider may advise you to discontinue a ketogenic diet. Typically that means you should eat a balanced diet and avoid overloading on refined foods and those that contribute to inflammation, including:

As with any treatment, only modify your diet under a qualified healthcare provider’s supervision, like anutritionistor dietician.

Foods You Should Eat

Focusing on fiber-rich, complex carbohydrates, primarily plant-based foods, can help rebalance your gut microbiome. Complex carbs take longer than simple carbs (like sweets and refined sugar) to digest, allowingblood sugarto rise more slowly.

In addition, since PP is an inflammatory condition, upping your intake ofanti-inflammatory foodscould also support healing. Anti-inflammatory foods include:

In addition to diet modification, prurigo pigmentosa treatment includes medication, such as:

A recent study evaluated treatment outcomes in PP. The systemic review included 115 studies, and among the participants who had changed their diet before coming down with PP, 40% had started a ketogenic diet.

The review also found that corticosteroids were effective 13% of the time, while doxycycline ultimately resolved the condition at 52%. For 3.5% of participants, diet alone resolved the condition.

Summary

Prurigo pigmentosa is an inflammatory condition that results in a blister-like rash. The ketogenic diet sometimes precedes the condition, so some call it “keto rash.” Some research has investigated the role of reversing ketosis in healing PP. Doing so involves reintroducing carbs and eating an anti-inflammatory diet. One study found limited results with diet alone, but it showed significant improvement compared to medication or diet alone when combined with antibiotics.

A Word From Verywell

While the keto diet is popular for producing quick weight loss results, it does come with risks. That’s why it’s crucial to work with a healthcare provider when considering modifying your diet, including treating PP. If you’re worried that your rash might be PP, it’s best to receive a medical evaluation and treatment.

Learn MoreKeto and Long-Term Health Risks

According to one study, PP tended to resolve within two weeks to a month with treatment.

Things that cause PP are the same things that can exacerbate it or cause it to recur. These risk factors include sweat, friction, ketosis, food restriction, pregnancy, eczema, diabetes, Sjögren’s disease, and some bacterial infections.

7 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.American Osteopathic College of Dermatology.Prurigo pigmentosa.Wong M, Lee E, Wu Y, Lee R.Treatment of prurigo pigmentosa with diet modification: A medical case study.Hawaii J Med Public Health. 2018;77(5):114-117.Academy of Nutrition and Dietetics.What is the ketogenic diet?Masood W, Annamaraju P, Uppaluri KR.Ketogenic diet. [Updated 2021 Nov 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing.American Heart Association.Carbohydrates.Johns Hopkins Medicine.Healthy eating tips to ease chronic inflammation.Mufti A, Mirali S, Abduelmula A, et al.Clinical manifestations and treatment outcomes in prurigo pigmentosa (Nagashima disease): A systematic review of the literature.JAAD Int. 2021;3:79-87. Published 2021 Apr 10. doi:10.1016/j.jdin.2021.03.003

7 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.American Osteopathic College of Dermatology.Prurigo pigmentosa.Wong M, Lee E, Wu Y, Lee R.Treatment of prurigo pigmentosa with diet modification: A medical case study.Hawaii J Med Public Health. 2018;77(5):114-117.Academy of Nutrition and Dietetics.What is the ketogenic diet?Masood W, Annamaraju P, Uppaluri KR.Ketogenic diet. [Updated 2021 Nov 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing.American Heart Association.Carbohydrates.Johns Hopkins Medicine.Healthy eating tips to ease chronic inflammation.Mufti A, Mirali S, Abduelmula A, et al.Clinical manifestations and treatment outcomes in prurigo pigmentosa (Nagashima disease): A systematic review of the literature.JAAD Int. 2021;3:79-87. Published 2021 Apr 10. doi:10.1016/j.jdin.2021.03.003

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

American Osteopathic College of Dermatology.Prurigo pigmentosa.Wong M, Lee E, Wu Y, Lee R.Treatment of prurigo pigmentosa with diet modification: A medical case study.Hawaii J Med Public Health. 2018;77(5):114-117.Academy of Nutrition and Dietetics.What is the ketogenic diet?Masood W, Annamaraju P, Uppaluri KR.Ketogenic diet. [Updated 2021 Nov 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing.American Heart Association.Carbohydrates.Johns Hopkins Medicine.Healthy eating tips to ease chronic inflammation.Mufti A, Mirali S, Abduelmula A, et al.Clinical manifestations and treatment outcomes in prurigo pigmentosa (Nagashima disease): A systematic review of the literature.JAAD Int. 2021;3:79-87. Published 2021 Apr 10. doi:10.1016/j.jdin.2021.03.003

American Osteopathic College of Dermatology.Prurigo pigmentosa.

Wong M, Lee E, Wu Y, Lee R.Treatment of prurigo pigmentosa with diet modification: A medical case study.Hawaii J Med Public Health. 2018;77(5):114-117.

Academy of Nutrition and Dietetics.What is the ketogenic diet?

Masood W, Annamaraju P, Uppaluri KR.Ketogenic diet. [Updated 2021 Nov 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing.

American Heart Association.Carbohydrates.

Johns Hopkins Medicine.Healthy eating tips to ease chronic inflammation.

Mufti A, Mirali S, Abduelmula A, et al.Clinical manifestations and treatment outcomes in prurigo pigmentosa (Nagashima disease): A systematic review of the literature.JAAD Int. 2021;3:79-87. Published 2021 Apr 10. doi:10.1016/j.jdin.2021.03.003

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