Dermatitis herpetiformis causes an itchy, bumpy skin rash. It is rare, and generally associated with gluten intolerance and coeliac disease. A strict gluten-free diet usually reduces or eliminates the rash, and medication can help relieve symptoms as the diet takes effect.
What causes dermatitis herpetiformis?
There is a close relationship between dermatitis herpetiformis and coeliac disease.
- Most people with dermatitis herpetiformis have some gluten intolerance.
- Some people with coeliac disease have dermatitis herpetiformis.
- Some people with dermatitis herpetiformis have a close relative with dermatitis herpetiformis or coeliac disease.
- Dermatitis herpetiformis and coeliac disease can be associated with similar gene mutations.
Dermatitis herpetiformis symptoms
Dermatitis herpetiformis causes a bumpy skin rash with tiny blisters. The rash can be extremely itchy, and if you have the condition, you might feel itching or burning before it appears. The rash usually appears in a symmetrical pattern on the following areas of the body:
- the outside of the elbows
- the knees
- the scalp
- the face
- the forearms
- the lower back and buttocks
- the shoulder blades
The rash appears when someone eats gluten. Their immune system produces antibodies to attack the gluten proteins. These antibodies then travel through the bloodstream and build up under the skin, causing the rash.
The rash can come and go over time and sometimes leaves pale or darker patches of skin. It is not contagious.
Dermatitis herpetiformis diagnosis
If they suspect you have dermatitis herpetiformis, your doctor is likely to refer you to a dermatologist (a skin specialist) for a diagnosis. The condition can look like herpes, eczema, scabies or contact dermatitis.
You are likely to have blood tests, and might also have a biopsy.
If the doctor diagnoses dermatitis herpetiformis, you may be referred to a gastroenterologist who can investigate whether you have coeliac disease.
Dermatitis herpetiformis prevention and treatment
Most people manage the condition with a gluten-free diet and with medications to treat the rash.
If you rely on diet alone, it can take 6 to 24 months after removing gluten from your diet for the rash to disappear. Therefore, people commonly take medication during this period to reduce the rash symptoms.
You might need medication for a year or 2. Because of possible side-effects, your doctor will monitor your health while you’re taking these medications.
Although diet and medication can treat the symptoms, dermatitis herpetiformis will not go away. If you have the condition, you will need to eliminate gluten from your diet for life.
When to seek help
If you think you might have dermatitis herpetiformis, you should see your doctor to get a diagnosis and begin treatment if necessary.
Dermatitis herpetiformis might be a sign that you are at risk of coeliac disease (if you don’t already have it) or other health conditions. Since your small intestines might be damaged, you could unknowingly have a nutritional deficiency or other complications.
Being aware of your condition will help you get the appropriate treatment for any of these associated conditions if they arise.
You can find out more from Coeliac Australia's website at www.coeliac.org.au.
Learn more here about the development and quality assurance of healthdirect content.
Last reviewed: June 2020