Prurigo nodularis is a skin condition that, like eczema, causes intense itching. But what is prurigo nodularis and how is it different from eczema? This article explores the two skin conditions, providing a brief background and helpful tips for those itching to know more.

What is prurigo nodularis?

Prurigo nodularis is a long-term inflammatory skin condition that presents as very itchy “nodules”, or spots, that can emerge across the body, arms and legs.¹

Prurigo nodularis is a relatively rare condition, affecting less than 1% in England. Although prurigo nodularis can affect any age or sex, the condition is more likely to affect:²

• People assigned female at birth, compared to people assigned male at birth
• People with coloured skin, compared to people with white skin colour
• Middle-age people in the 50 to 60 age group

It is uncommon to need more than a simple clinical consultation to diagnose prurigo nodularis. The condition is diagnosed by observing the appearance of the skin and asking about the symptoms. Further laboratory tests can be used to confirm a diagnosis, but are not always necessary.³

The size of the nodules typically ranges from a few millimetres, up to two centimetres. Some people may find the nodules cause burning or stinging pain, but severe itchiness is the surest sign of prurigo nodularis. The intense itchiness can lead to bleeding as repeated scratching breaks the skin of the nodules.^3,4

People with prurigo nodularis can find their mental health to be affected. In addition to the risk of low self-esteem that is common with any skin problem, the intense itching itself is irritating. Prurigo nodularis is severe, and it is difficult to ignore the urge to scratch. The physical discomfort of prurigo nodularis is of particular concern when it interrupts sleep. Disturbed sleep can further impact the skin’s health due to the build-up of stress.

What is the cause of prurigo nodularis?

The cause of prurigo nodularis is not well understood. It is thought to be a reaction to long-term itching and scratching. Prurigo nodularis has been linked to various causes, including aluminium toxicity during kidney dialysis, hepatitis C, HIV and stomach cancer. In any case, people with prurigo nodularis see an increased reaction from their skin and immune systems, which leads to excess inflammation, itching, and eventually the development of the skin nodules.⁴

Most people with prurigo nodularis tend to have another skin condition, with eczema being the most commonly associated condition.

What is eczema?

Eczema is another type of inflammatory skin condition that causes itchiness. In people with eczema, the immune system overreacts, triggering a large inflammatory response when the body comes into contact with certain triggers.

How is prurigo nodularis related to eczema?

Both eczema and prurigo nodularis are skin conditions that are characterised by itchy and inflamed skin. It is possible to have both prurigo nodularis and eczema at the same time. However, eczema and prurigo nodularis are considered different skin conditions.

Visually, the two skin conditions appear quite differently. Prurigo nodularis is identified by smaller nodules that dot the skin, whereas eczema affects whole patches of skin, causing them to appear dry, red and cracked.

People with eczema are likely to have a good idea of what causes or triggers a flare-up. These can range from dry skin, irritants, allergens, and stress. Therefore, it can be easier to manage and prevent, by avoiding the triggers. In contrast, the causes of prurigo nodularis remain unclear.⁴

How can I treat prurigo nodularis?

Although there is no instant cure for prurigo nodularis, there are treatments that can help manage the condition.

First-line treatment for prurigo nodularis is very similar to treatment for eczema, as both focus on addressing itching and inflammation. By reducing the frequency and intensity of itching, the skin is allowed to recover on its own.¹

• Avoid scratching: Try to avoid damaging the skin when itching by trimming the fingernails, and wearing cotton gloves to bed to prevent tearing the skin while asleep. Calamine lotion and anti-itch creams can be used to relieve the itching sensation
• Emollients: Dry skin can be a cause for itchiness. Liberally apply emollients (moisturisers) to prevent the skin from drying out. Be wary of emollients that contain alcohol or fragrances. These may not be suitable for sensitive skin as they can dry and irritate the skin further
• Allergy tablets: Antihistamine tablets can be taken to reduce itching. Some antihistamines (such as chlorphenamine) cause drowsiness as a side effect. This may be particularly helpful if itching makes it difficult to fall asleep at night
• Steroid creams: Short-term treatment courses with steroid creams can be used to address both inflammation and itching. It is best to avoid long-term use, which can lead to side effects including skin-thinning, making the skin more delicate. Apply steroid creams according to the doctor’s instructions. As a general rule, use the weakest strength that is effective, for the shortest period of time

It can take some trial and error to find a treatment or combination of treatments, that works best for the individual. Further treatment alternatives can be tried if the previous treatment methods didn’t work, or if the condition keeps returning.⁴

• Vitamin creams: Vitamin D3 (calcipotriol) creams can be applied to treat itchy skin conditions. Vitamin D3 has been shown to reduce components in the immune response, which leads to less inflammation
• Phototherapy: Phototherapy (UV light therapy) involves exposing the skin to ultraviolet light. The light shuts down certain immune cells in the skin to reduce itching. Treatment courses are usually scheduled three times a week, lasting for a few months
• Capsaicin creams: Capsaicin is a compound found in chilli peppers. The first few applications of capsaicin creams can cause a sensation of itching and burning. Over time, the capsaicin can completely relieve itching sensation after being used multiple times a day for several weeks. However, in some cases, itching may return after the treatment is stopped

FAQs

Is prurigo nodularis serious?

While not life-threatening, the itch associated with prurigo nodularis is intense and can be severe enough to interrupt sleep and affect the person’s self-body image. Creams and treatments are available to help ease the itch from prurigo nodularis.

Which cream is best for prurigo nodularis?

Steroid creams are used to reduce skin inflammation and itch. There are a range of strengths available. Mild steroid creams (e.g. hydrocortisone cream) can be bought over the counter at pharmacies, but stronger strengths require a prescription from a doctor.

Can I use multiple creams at the same time to treat prurigo nodularis?

It is a good idea to use both emollients and corticosteroids. Emollients are suitable for moisturising dry skin, whereas steroid creams relieve skin inflammation.

Emollients should be applied frequently to prevent dry skin from further aggravating the itch. On the other hand, it is best to apply steroid creams thinly and sparingly to reduce the risk of side effects.

It is recommended to leave at least 30 minutes between applications of steroid cream and emollient. This is to allow time for the steroid cream to be absorbed into the skin without being diluted by the emollient.

How can I get rid of prurigo nodularis?

Prurigo nodularis is a difficult condition to treat as there are no instant cures. Currently, available treatments aim to prevent itching and allow the skin to heal. A combination of different treatments can be trialled to see which is most effective for the individual.

Is prurigo nodularis contagious?

Prurigo nodularis is not a contagious disease caused by bacteria, viruses or fungi. This means that people with prurigo nodularis cannot pass or spread it to other people.

However, as with most chronic inflammatory skin conditions, it is recommended to maintain good hygiene especially when itching the affected skin. This is because bacteria can spread from the fingers and into the scratches, which can lead to infection. Be sure to wash your hands frequently and maintain short fingernails that are easier to clean.

Summary

Overall, prurigo nodularis is very similar to eczema, in that they are both very itchy skin conditions. However, the two conditions look quite different. Eczema is known to react to certain triggers, while the cause of prurigo nodularis is still uncertain. Both conditions can be managed by relieving itching and inflammation using creams, tablets and UV light therapies.