What are the aims of this leaflet?
This leaflet has been written to help you understand more about nodular prurigo. It tells you what it is, what causes it, what can be done about it, and where you can find out more about it.
What is nodular prurigo?
‘Pruritus’ is the medical term for itching. ‘Prurigo’ is a related word, which describes the changes that appear in the skin after it has itched and been scratched for a long time. In nodular prurigo these changes take the form of firm very itchy bumps (nodules) on the skin’s surface. These can resolve when the person stops scratching the area, although in many cases this can be very difficult without proper and sometimes prolonged treatment.
What causes nodular prurigo?
It is not known what causes nodular prurigo, or makes the skin react in this way. However, once the skin has become itchy, scratching and rubbing will cause the skin nerve endings to become thicker, more irritable and cause more itching; this in turn will make the condition worse.
Nodular prurigo may start after an insect bite in a few people.
People under stress, are more likely to scratch. Stress can therefore make nodular prurigo worse.
Up to 80% of people with nodular prurigo are atopic and may have asthma, eczema or hay fever.
There are several medical conditions that can be associated with nodular prurigo that may need to be further investigated.
Is nodular prurigo hereditary?
What are the symptoms of nodular prurigo?
The itching can be very distressing and can be severe enough to regularly disturb sleep at night and daytime activities.
What does nodular prurigo look like?
The skin shows many hard bumps that are intensely uncomfortable. They may be darker than the skin around them. They have a rough, rather thickened surface and may have an overlying scab or scratch marks on top. The lumps are usually less than 1cm in diameter and can feel firm, be tender, as well as crusty and itchy.
The arms and legs are the most commonly affected areas, but the back, buttocks, shoulders and chest can be affected too. There may additionally be some discoloured scars in the affected areas from deep scratching. Nodular prurigo is most common between 20 and 60 years of age, however, may be present in any race and equally between sexes. The number of nodules may increase with time.
How is nodular prurigo diagnosed?
Symptoms of itching, and the typical skin lesions described above, are usually enough to make the diagnosis of nodular prurigo. If there is any doubt then your doctor can carry out a skin biopsy (cutting out one of the bumps under a local anaesthetic to examine under the microscope); this can help to confirm the diagnosis. Blood tests may be taken to check for other conditions that can make the skin itchy e.g. iron-deficiency anaemia, kidney or liver disease, thyroid function tests and diabetes mellitus.
Can nodular prurigo be cured?
No. It is difficult to clear nodular prurigo, but it can usually be controlled and should therefore gradually improve over time. People are advised not to scratch or rub the nodules, which may slowly resolve and disappear. However, the area of skin may still be very itchy for several weeks.
How can nodular prurigo be treated?
The treatments for nodular prurigo are aimed at stopping the skin itching:
A steroid cream or ointment will usually be suggested as an attempt to reduce the inflammation in the skin. It should be applied once or twice a day. The strength of the steroid used will depend on the age, where the nodules are, and on the severity of the problem. Sometimes injecting a small amount of a steroid into a particularly itchy nodule, or covering it with steroid tape, can help.
Covering the skin with an ointment or a paste bandage can increase the effect of the steroid. It also helps to reduce the itch and the damage to the skin caused by scratching or rubbing.
An antihistamine tablet or syrup can help to reduce the feeling of itch. Those that work best for nodular prurigo can cause drowsiness, so should not be taken if driving or using machinery. If you require antihistamine tablets or syrup that would not cause drowsiness, it would be advisable to consult your pharmacist. Some tablets have both antihistamine and anti-stress effects, such as doxepin, and can be helpful taken at night.
Ultraviolet light treatment, given in the hospital, can help to reduce the quantity of nodules, new nodules appearing or the itch/scratch syndrome.
Psychological support or medication to relieve anxiety or depression may be offered by your doctor.
If nodular prurigo is very severe and causing distress, immune-suppressing treatments such as steroids, ciclosporinor azathioprinecan be prescribed to help reduce inflammation; it is important to note that these treatments may cause additional side effects. Thalidomide can help severe nodular prurigo but it is usually not given to females who might possibly become pregnant as it can damage the unborn baby.
Self care (What can I do?)
The most important but hardest thing to do is to stop scratching.
Anything you can do to take your mind off the itching will help to reduce or stop the scratching. Ask your family and friends to remind you gently if they notice that you are scratching – it is easy to get into the habit of scratching, and you can do it without being aware.
You may find that laying a cool damp flannel on the skin can reduce the feeling of itch. A cooled emollient (moisturiser) which has been kept in the refrigerator, or has added menthol, may also help.
Keep your bedroom cool and do not sleep with heavy or heat retaining bedclothes. If you are hot and itchy during the day a fan can help to cool the skin down.
Emollients (moisturisers). Patients with nodular prurigo may have dry skin, and therefore emollients may help ease itching, reduce scaling, soften cracked areas and help the penetration of other topical treatments. They should be used as a soap substitute when bathing or washing and should also be put on before treatment.
CAUTION: This leaflet mentions ‘emollients’ (moisturisers). Emollients, creams, lotions and ointments contain oils which can catch fire. When emollient products get in contact with dressings, clothing, bed linen or hair, there is a danger that a naked flame or cigarette smoking could cause these to catch fire. To reduce the fire risk, patients using skincare or haircare products are advised to be very careful near naked flames to reduce the risk of clothing, hair or bedding catching fire. In particular smoking cigarettes should be avoided and being near people who are smoking or using naked flames, especially in bed. Candles may also risk fire. It is advisable to wash clothing daily which is in contact with emollients and bed linen regularly.
Where can I get more information?
Links to patient support groups:
Nodular Prurigo International
136 Bedford Street South
Liverpool, L7 7DB
Web links to detailed leaflets:
For details of source materials used please contact the Clinical Standards Unit (firstname.lastname@example.org).
This leaflet aims to provide accurate information about the subject and is a consensus of the views held by representatives of the British Association of Dermatologists: individual patient circumstances may differ, which might alter both the advice and course of therapy given to you by your doctor.
This leaflet has been assessed for readability by the British Association of Dermatologists’ Patient Information Lay Review Panel
BRITISH ASSOCIATION OF DERMATOLOGISTS
PATIENT INFORMATION LEAFLET
PRODUCED AUGUST 2004
UPDATED MAY 2010, MAY 2013, MAY 2016
REVIEW DATE MAY 2019