Medically reviewed by Jamie Johnson, RDN
Keto rash, or prurigo pigmentosa, is a rare inflammatory skin problem. Also called Nagashima disease, the keto rash causes an itchy rash with vesicles (fluid-filled blisters). It often appears on your neck and trunk. The blisters change and crust into darker-pigmented spots that form a netlike pattern.
The keto rash is often linked to the ketogenic (keto) diet or health conditions that produce ketosis. In this state, your body uses stored fat rather than glucose for energy. The ketogenic diet is a low-carbohydrate, high-fat eating plan. It is most often recommended to treat people with epilepsy that is hard to control.
Treatments for the keto rash include home cures like increasing carbohydrate intake and making up for vitamin deficiencies. Antibiotics and other drugs are often useful when these treatments don’t work.
This article explains all you need to know about the keto rash, its causes, treatments, and ways to prevent it.
What Does the Keto Rash Look Like?
The appearance of a keto rash can vary based on your skin tone and texture. Most case reports are in people in Asia and the Middle East, with some reports in White or Hispanic people. Descriptions of the rash in people of darker skin tones are lacking.
The condition includes the following characteristics:
Inflamed, itchy, red papules (small, well-defined skin bumps) or vesicles
Symmetrical distribution of spots on your trunk and neck
Occasional appearance of spots on your face, scalp, and suprapubic region (lower abdomen and groin)
Rare involvement of mucous membranes, hair, and nails
Formation of a netlike pattern of dark spots as the inflammatory phase of the rash ends and the bumps scale and crust
While a keto rash can affect anyone, it is most common among people of Asian descent. It affects women twice as often as men, though it may be due to a higher prevalence of dieting behaviors among women than men.
A keto rash typically occurs 31 days after starting a keto diet. For most people, the rash subsides about 18 days after ending the keto diet.
A Note on Gender and Sex Terminology
Verywell Health acknowledges that sex and gender are related concepts, but they are not…