What is nappy rash?
Nappy rash (diaper dermatitis) is an inflammation of the skin in the nappy area. Various factors can play a role in this uncomfortable problem for babies.
What does it look like?
The skin in the nappy area is red and scaly. Often the groin and the cleft of the buttocks are spared. Nappy rash is much less common since the introduction of modern disposable nappies, but even so about half of all babies go through a period of it in their first 2 years. Besides redness, blisters, small wounds or scaling can sometimes occur.
Who gets it?
In the first 3 weeks of life nappy rash hardly occurs. From the 3rd week onwards it can develop, and most complaints occur between the 7th and 12th month. Boys get it as often as girls.
How does nappy rash develop?
Several factors contribute, and not every case is the same, because the factors play a different-sized role in each child. The most important are:
- Water. Prolonged contact with moisture softens the skin, so it can be damaged more easily (for example by rubbing), and irritating substances can penetrate more easily. Prolonged contact with water alone (for example in a wet nappy) is already enough to develop eczema.
- Friction. Friction between the skin and the nappy can damage the skin. This is clearly seen in typical cases: where the skin makes direct contact with the nappy surface (inner thighs, buttocks, genitals) the rash is usually worst, so the material of the nappy’s inner surface plays a considerable role.
- Urine. Nappy rash used to be blamed mainly on the ammonia in urine. Research shows ammonia can somewhat worsen existing nappy rash, but the main culprit is very probably the water in the urine rather than the ammonia.
- Stool. Faeces are very damaging to the skin. Because a “dirty nappy” is normally noticed and changed quickly, the stool does not get time to do its damage, but it contains enzymes and other proteins (including from the pancreas) that can easily damage the skin. If the skin is already damaged by nappy rash, worsening happens extra quickly — so changing quickly is important.
- Yeast infection. A yeast infection in the nappy area (mainly Candida albicans) is found much more often in children with nappy rash. With a massive infection, the doctor speaks not of nappy rash but of a candida infection. Candida thrives in a warm, moist environment, so it settles easily in the nappy area, all the more if the skin is already damaged. A candida infection can be recognised by the scaly edges of the red spots and the “islands off the coast”: small red spots with a scaly edge just outside the large red patches. Sometimes small white pustules are also present.
Contrary to what used to be thought, bacterial infections do not seem to play a major role in nappy rash.
How is nappy rash best treated?
- Use good disposable nappies. Modern nappies contain super-absorbent gels and keep the skin dry longer; the inner lining should be of a soft material so there is no rough friction.
- Even the best nappies eventually use up their absorption capacity, so change nappies regularly.
- After a “dirty nappy”, clean the bottom with a washcloth and clean water.
- Before putting on each clean nappy, apply a protective skin ointment; a barrier ointment with as few additives as possible is wise.
- In severe cases it may be necessary to apply a mild corticosteroid ointment to the inflamed skin temporarily; this can be prescribed by the doctor.
- If the doctor has established a candida infection, a special anti-yeast cream is usually prescribed.
What is the outlook?
With the above measures the nappy rash usually disappears quickly. If, despite good care, an inflammation of the nappy area persists, it is advisable to see the doctor again: several skin conditions can look like nappy rash but are not, and so do not respond adequately to nappy-rash treatment; further investigation may then be needed.
How can I prevent nappy rash?
Use good nappies, change them regularly, clean the bottom with clean water, and protect the skin with a good barrier ointment.
When to see a doctor
See a doctor if the rash does not improve with good care, if there are blisters, open sores, pustules or scaly-edged spots (which can indicate a yeast infection), or if your baby seems unwell.