Nappy Rash: Causes, Treatment and How to Prevent It Coming Back

Nappy rash affects most babies at some point during the nappy years. For many it's mild and resolves quickly with simple treatment — but for some, it becomes a recurring or stubborn problem that needs more targeted care.

What nappy rash looks like

Classic nappy rash is red, inflamed skin in the nappy area — the buttocks, genitals, inner thighs, and anywhere skin contacts the wet nappy. It can range from:

• Mild pinkness and slight roughness
• More pronounced redness with small spots or bumps
• Broken, raw, or weeping skin in severe cases

What causes nappy rash?

Prolonged contact with urine and faeces: The most common cause. Urine on its own has some irritant properties; faeces (especially with gut bacteria) can cause significant irritation when left in contact with skin.

Friction: Nappy edges rubbing against skin, particularly in the creases.

Introducing new foods: Changes in stool composition during weaning or when starting new foods can cause or worsen rash.

Antibiotic use: Antibiotics (in baby or breastfeeding mum) disrupt the gut microbiome and can cause frequent, looser stools that increase rash risk — and can also lead to thrush (see below).

Nappy type: Some babies react to fragrances, dyes, or materials in certain brands.

Skin conditions: Underlying eczema can make the nappy area more prone to irritation.

Treatment

Change nappies frequently: This is the most important intervention. More changes = less skin contact with irritants.

Clean gently: Use plain water and soft cotton wool or a fragrance-free wipe. Avoid harsh fragrances, alcohol-based products, or vigorous rubbing.

Pat dry, don't rub: Ensure the skin is completely dry before applying cream.

Use a barrier cream: Apply a thick layer of zinc oxide paste (Metanium, Sudocrem) or a simple barrier cream (petroleum jelly) at every change. The goal is a physical barrier between skin and nappy — apply generously.

Nappy-free time: Allowing air to reach the skin genuinely helps. Even 10–20 minutes without a nappy a couple of times a day makes a difference.

Choose a breathable nappy: Some families find switching brands helps; if using reusables, ensure inserts are absorbing well.

Most simple nappy rash resolves within 3–4 days of consistent treatment.

Thrush nappy rash — when it's something different

If rash doesn't improve after 3–4 days of standard treatment, consider Candida (thrush). Clues:

• Bright red rash with a clearly defined, raised edge
• Satellite spots — small red spots outside the main rash area
• Rash concentrated in the skin folds/creases (unlike simple irritant rash, which often spares creases)
• Not responding to standard barrier creams

Treatment: antifungal cream (Clotrimazole/Canesten) applied to the rash area at every nappy change, typically for 7–14 days. This is available over the counter — your pharmacist can advise. If baby also has white patches in the mouth (oral thrush), both need treating simultaneously.

When to see your GP

• Rash with blisters, pus, or spreading red streaks
• Rash accompanied by fever
• Rash that hasn't improved after 7 days of treatment
• Very raw or broken skin
• You suspect thrush and want confirmation or prescription treatment

Prevention

• Change nappies promptly — aim for every 2–3 hours or immediately after a poo
• Use barrier cream at every change (even when skin looks fine) if your baby is prone to rash
• Avoid fragranced wipes, soaps, or bath products in the nappy area
• If using reusable nappies, ensure they're washed without fabric softener and rinsed thoroughly
• If your baby is on antibiotics, consider a gentle probiotic (ask your pharmacist or GP) and increase nappy change frequency
• When starting new foods during weaning, introduce them gradually — sudden changes in stool composition are a common trigger