What Is Prurigo Nodularis?
Prurigo nodularis is an extremely itchy skin condition. It causes a rash that often includes hard lumps called nodules. You might also hear it called nodular prurigo.
Doctors don’t know exactly what causes it, but it isn’t contagious. It’s most common in people who are middle aged. You’re also more likely to have it if you’re Black.
Causes
Doctors believe prurigo nodularis comes from a problem with your immune system and the nerves in your skin that cause you to feel itchiness more than normal.
Many people who get it are already dealing with a health condition that causes itchy skin. Most often, it’s a skin problem such as:
- Atopic dermatitis (eczema)
- Contact dermatitis
- Extremely dry skin
- Scabies
Or it may be a condition that affects other parts of your body but also causes itching, like:
- Allergies
- Certain kinds of cancer, including lymphoma and skin cancers
- Diabetes
- HIV that’s untreated
- Infections from bacteria like tuberculosis, viruses like herpes, and some parasites
- Kidney disease
- Liver disease, including hepatitis C
- Nerve problems
- Psychological problems including anxiety and depression
- Thyroid disease
Sometimes it happens on its own with no other cause.
Symptoms
Prurigo nodularis causes intense itching that’s almost impossible not to scratch.
- You may feel a burning or stinging sensation.
- The itch may come and go, or you may feel it all the time.
- It can be so bad you have trouble sleeping or handling your daily life.
Scratching causes a rash to form, which then itches even more.
- The rash typically appears after 6 weeks of itching.
- You may have small bumps called papules, larger bumps called nodules, or raised patches called plaques.
- The bumps can be different sizes and thicknesses. They may be the same color as your skin, or pink, red, brown, or black.
- Your rash may be only in a few places or all over. You may have a few bumps, or hundreds.
- The rash is usually on your arms, legs, torso, upper back, and the back of your scalp. It appears less often in places that are harder to scratch.
Testing and Getting a Diagnosis
A doctor who specializes in skin conditions (called a dermatologist) may be able to tell you have prurigo nodularis by looking at your rash, especially if you have one of the health conditions that usually go along with it. But it can be mistaken for other itchy skin conditions. You may need tests, like:
- Biopsy: Your doctor scrapes off or cuts out a tiny piece of skin to look at the cells under a microscope.
- Dermoscopy: This procedure uses a magnifying scope with a special light that allows your doctor to see beneath your skin’s surface without cutting into it.
If you aren’t aware of another cause of the itching, your doctor may do blood tests to check for infection and to test how well your liver, kidney, and thyroid are working.
Questions for Your Doctor
It can be helpful to write down questions to ask your doctor. You may want to find out:
- Is there any health condition I might not know about that’s causing the itch?
- What treatment do you recommend?
- Will there be side effects?
- When can I expect to see results?
- How can I tell if I’ve developed a skin infection?
- What else can I do to ease my symptoms?
Treatment Path
The sooner you get treatment, the more likely you are to get relief from prurigo nodularis. If you have itchy bumps on your skin for more than 2 weeks, see a dermatologist.
There are no treatments specifically approved for prurigo nodularis. But the same strategies used with other skin conditions can help.
Topical treatments. Medicated creams, lotions, and ointments can ease the itch or numb your skin. You can try over-the-counter products that contain:
- Calamine
- Camphor
- Capsaicin (the spicy ingredient in chili peppers)
- Menthol
- Phenol
- Pramoxine
Other medicines available by prescription include:
- Calcineurin inhibitors (pimecrolimus, tacrolimus) to calm inflammation
- Vitamin D (calcipotriene)
Antihistamines. These control itching and can help you sleep.
Steroids. You can get these drugs as a topical treatment or a pill. They can also be injected directly into rash nodules.
Phototherapy. In this treatment, your skin is exposed to special light for a certain period of time. It can treat a rash covering a large area. Light from a laser can target smaller areas.
Cryotherapy. Extreme cold can be applied to individual rash nodules. This treatment can cause scarring on darker skin.
Psychotherapy. If your doctor doesn’t find physical cause, they may refer you to someone who can look for a psychological cause. A therapist can also teach you ways to ignore the itch and stop scratching and help you deal with the challenges of living with the condition.
Immunosuppressants. These drugs work throughout your body to calm your immune system and ease inflammation and itching. You may get them if your rash is very bad and widespread and doesn’t respond to other treatments. Examples include:
- Azathioprine
- Cyclosporine
- Methotrexate
- Monoclonal antibodies (dupilumab, nemolizumab)
Other medications sometimes used to stop the itching of prurigo nodularis include:
- Antidepressants
- Gabapentin
- Neurokinin-1 receptor antagonists (aprepitant, serlopitant)
- Opioid receptor antagonists (naloxone, naltrexone)
- Sedatives, especially if itching is making it hard for you to sleep
- Thalidomide or lenalidomide
If you have another health problem that’s contributing to the itch, getting treatment for that can help.
Taking Care of Yourself With Prurigo Nodularis
Not scratching is key. Try these tips to reduce itching and soothe your skin when it flares:
- Moisturize your skin several times a day.
- Use only mild cleansers and skin care products. Look for ones made for sensitive skin.
- Wash in warm water, not hot.
- Wash gently. Don’t scrub your skin.
- Stay cool. Wear lightweight fabrics that breathe, and sleep under a fan.
- When the urge to itch strikes, try putting an ice pack or cold compress on your skin, or keep a bottle of lotion in the refrigerator.
To prevent damaging your skin when you do scratch:
- Keep your nails short.
- Cover your skin with long sleeves and pants.
- Wear gloves to bed.
- Wrap tape or bandages around areas where the rash is worst.
What to Expect
Prurigo nodularis can be very uncomfortable. Your skin may feel dry and inflamed, and so itchy it may seem impossible not to scratch. You may have trouble sleeping and getting through the day. Rash bumps or patches can crack, bleed, and become infected.
It can take time for treatment to work, and you may have to try more than one to get relief. The condition can last months or years.
How the Condition May Change Over Time
The skin where the prurigo nodularis rash appears can become thick and hard. It may leave dark spots or scars after it heals.
When the condition is active, fewer nerve fibers grow in the epidermis, the outer layer of skin. And extra nerve fibers grow in the dermis, the deepest skin layer. Usually, that goes back to normal after treatment.
Emotional/Mental Health
Prurigo nodularis can have a serious impact on your quality of life. You may be constantly distracted by the scratching or embarrassed by the appearance of your skin. It can cause you to:
- Get anxious or feel depressed
- Miss work
- Avoid being around other people
Where to Find Support
If you’re having trouble dealing with your prurigo nodularis, ask your doctor for a referral to a therapist.
It can help to know that other people have this condition and might have ideas that could help you. Check the internet for support groups in your area or online. There are several on Facebook, including:
You may find it empowering to take part in a clinical trial looking for a better understanding of the disease or a new treatment. Search Clinicaltrials.gov for studies in your area.
Tips for Living With Prurigo Nodularis
It can be very tough to live with the discomfort of this skin condition.
- Figure out whether something triggers your itching and see if you can avoid it. Common triggers include stress, heat, and sweat.
- Do your best not to scratch.
- Be patient. It can take time to see results from treatment. Stick to your plan, but talk to your doctor about other options if you aren’t getting relief.