Nappy rash is one of the most common skin concerns in a baby’s first year — and yet, it can feel completely overwhelming when it suddenly shows up on your little one’s soft skin. Is this just a mild flare-up? Or something more serious? Should you wait it out… or worry?
As mums, it’s easy to second-guess ourselves — especially when we’re tired, emotional, and trying to do everything right. The truth is: most nappy rash is mild and clears up quickly. But sometimes it can turn into something more severe, painful, or even bleeding, and knowing the difference can help you act quickly — without panic.
In this guide, we’ll walk you through:
- What causes nappy rash in the first place
- How to tell if it’s mild or more serious
- What to do at home — using natural, gentle remedies
- When to speak to a health visitor or GP
Whether it’s your first nappy rash or the worst one you’ve seen, this article is here to help you feel calm, clear, and confident in how to care for your baby’s sensitive skin.
What Causes Nappy Rash?
Nappy rash can appear suddenly — sometimes within hours — and often without any obvious reason. One moment your baby’s skin looks fine, and the next, it’s red, sore, and inflamed. So what actually causes nappy rash?
The Main Causes of Nappy Rash
Prolonged contact with moisture
The number one trigger is wetness. Even highly absorbent nappies can’t catch everything, and when skin is exposed to urine or poo for too long, it becomes irritated, soft, and vulnerable.
Friction and rubbing
Tight or ill-fitting nappies can cause chafing, especially when combined with moisture. This creates redness in the creases of the legs, bottom, or around the waist.
Changes in your baby’s poo
During teething, illness, or dietary changes, your baby’s stools can become more acidic. This increased acidity can irritate the skin and make it more prone to rash — even if you’re changing nappies frequently.
Frequent poos or diarrhoea
If your baby is going more often than usual (e.g., due to teething, food sensitivities, or antibiotics), the skin doesn’t have time to recover between changes. This can lead to persistent or worsening nappy rash.
Wipes, soaps, or scented products
Some babies have sensitive skin that reacts to:
- Fragrance in wipes
- Foaming cleansers or bubble baths
- Barrier creams with synthetic additives
If the rash seems to get worse after using a certain product, it’s worth switching to fragrance-free, natural alternatives.
Thrush or bacterial infection
In some cases, what looks like nappy rash is actually fungal (candida) or bacterial. These infections can develop when broken skin is exposed to dampness, and they often need targeted treatment from your GP.
Understanding what causes nappy rash is the first step toward preventing it — and knowing how to respond with care. In the next section, we’ll explore how to tell the difference between mild and severe nappy rash, and what signs to watch for.
Mild vs. Severe Nappy Rash: How to Tell the Difference
It’s natural to worry when you see your baby’s skin looking red or sore. But not all nappy rash is the same — and knowing whether it’s mild or more severe can help you respond calmly and confidently.
Here’s how to spot the difference.
🌿 Signs of Mild Nappy Rash
Mild nappy rash is extremely common, especially in the first year. It may look a little uncomfortable, but it usually resolves quickly with gentle care.
Look for:
- Slight redness or pinkness on the bottom or in skin folds
- No broken skin
- Baby seems mostly unbothered — still smiling, feeding, and sleeping normally
- Rash clears within a day or two with simple care
Mild nappy rash often appears after a long nap, teething poo, or warm day — and tends to clear up quickly when the area is kept clean and dry.
🔥 Signs of Severe Nappy Rash
Severe nappy rash is more than just a bit of redness — it often means the skin is very irritated, inflamed, or even broken. This kind of rash usually needs more intensive treatment and a bit more time to heal.
Look for:
- Deep redness, swelling, or inflammation
- Raised spots or open sores
- Bleeding or oozing skin (especially after wiping)
- Baby cries or flinches during nappy changes or when touched
- Rash spreads beyond the nappy area (e.g., thighs or lower belly)
- Doesn’t improve after 2–3 days of home care
This is often referred to as the worst kind of nappy rash, and it can be painful for your baby — especially when urine or poo touches raw skin.
If you suspect severe nappy rash, it’s okay to feel worried — but you’re not alone. With the right approach, most cases can be treated at home or with a little help from your GP or health visitor.
How Long Does Nappy Rash Last?
When your baby’s skin is sore, every hour can feel like forever — especially if you’re not sure how long the rash is supposed to last. The good news? Most nappy rash clears up quickly with the right care. But how long it lasts depends on what caused it and how severe it is.
Mild Nappy Rash
Mild nappy rash often looks pink or slightly red but doesn’t seem to bother your baby too much. If you act quickly — by keeping the area clean, dry, and protected with a gentle barrier cream — it can clear up within 1 to 3 days.
Things that help it heal faster:
- Changing nappies more frequently
- Using plain water or cotton wool to clean
- Avoiding fragranced wipes or soaps
- Giving your baby nappy-free time to let the skin breathe
- Applying a natural, breathable barrier balm after each change
Severe Nappy Rash
Severe nappy rash — especially when the skin is broken, bleeding, or infected — can take up to a week or more to heal. It often needs more intensive care and close monitoring. You may also need to strip back your skincare routine to avoid further irritation.
If it’s caused by fungal or bacterial infection, your GP may prescribe a special cream, and the healing process might take a little longer.
When to See a Doctor
You should contact your GP or health visitor if:
- The rash is worsening after 2–3 days of home care
- There are open sores, pus, or bleeding
- Your baby seems in real pain, stops feeding, or cries more than usual
- The rash is spreading beyond the nappy area
- You suspect thrush or another infection
Remember, you’re not overreacting — your instincts matter. If something feels off, it’s always okay to check in with a professional.
Severe Nappy Rash Treatment: What Really Helps
When your baby’s bottom is red, raw, or even bleeding, it can be heartbreaking. Severe nappy rash is painful — for them and for you. The good news is, with the right care, healing is absolutely possible. The key is to strip everything back and give the skin a chance to recover.
Here’s how to treat severe nappy rash gently and effectively at home.
Stop using fragranced or harsh products
Now is not the time for wipes with essential oils or bubble baths with “gentle” foam. Even natural-looking products can sting broken skin. Instead:
- Clean with warm water and cotton wool only
- Pat, don’t rub — and skip soap altogether
- Avoid anything scented, foaming, or antibacterial
Use a protective barrier with zinc oxide
A breathable barrier cream or balm with non-nano zinc oxide is ideal. Zinc oxide sits on the skin to protect it from urine and poo, while allowing it to heal underneath. Look for something fragrance-free, and avoid petroleum-based products that can trap moisture.
💗 Matylda Baby Balm was designed with this kind of skin in mind — combining zinc oxide with deeply nourishing tallow, calendula, and coconut oil.
Keep the area dry (but not over-washed)
It’s tempting to clean the rash constantly — but too much wiping can make it worse. Aim for:
- Gentle cleaning only when necessary
- Letting the skin fully dry before applying cream
- Allowing time without a nappy each day (even 10 minutes helps)
Change nappies more frequently
The skin needs a clean environment to recover. During a rash, change your baby’s nappy:
- Every 2 hours during the day, or as soon as it’s wet/soiled
- At least once during the night if you suspect dampness
(We’ll cover more on this in the next section.)
Watch for signs of infection
If you see:
- Bleeding, blistering, or open sores
- White patches (could indicate thrush)
- Yellow crusts or oozing
- Your baby seems distressed or feverish
Call your GP or health visitor. Sometimes severe nappy rash becomes infected and needs a prescribed cream.
Severe nappy rash isn’t your fault — and you don’t need a shelf full of products to treat it. Often, less is more. With a gentle barrier, a little air time, and lots of love, your baby’s skin can bounce back beautifully.
How Often to Change a Nappy With Rash
When your baby has a rash — especially a sore or severe one — keeping their skin clean and dry becomes your top priority. One of the most powerful things you can do is simply change their nappy more often than usual.
Change More Frequently Than You Think
With nappy rash, even a small amount of moisture sitting on the skin can worsen irritation. Aim to:
- Change every 2 hours during the day
- Immediately after every poo (no matter how small)
- Once during the night if they’ve had a long sleep stretch or if you know they’ve soiled the nappy
Even if the nappy feels only slightly damp, it’s worth changing — especially while the skin is healing.
Night-Time Tips
You don’t need to disrupt your baby’s sleep constantly, but during a flare-up:
- Use a high-absorbency nappy for overnight
- Apply a generous layer of barrier balm before bed
- Do a quick check and change if they wake naturally or if you’re doing a dream feed
Keep It Gentle Every Time
Frequent changing shouldn’t mean aggressive cleaning. Stick to:
- Warm water and soft cloth or cotton wool
- Patting dry, especially in skin folds
- Applying a breathable barrier cream to protect after each change
The goal is to reduce the amount of time the skin spends wet — not to scrub it clean. Sometimes just a warm, damp cloth and a little air time is enough.
By changing nappies often and using a gentle routine, you’re creating the ideal conditions for your baby’s skin to heal — without overloading it with products or stress.
When to See a Doctor or Health Visitor
Most cases of nappy rash — even the sore ones — can be managed at home with frequent changes, gentle care, and a soothing barrier balm. But sometimes, you need a little extra support. If your baby’s rash isn’t improving, or seems to be getting worse, it’s always okay to get help.
Here’s when to reach out:
Call your GP or health visitor if:
- The rash is not improving after 3 days of home treatment
- Your baby has open sores, blisters, or bleeding skin
- The rash is oozing, smells unusual, or looks infected
- You see white patches that could indicate thrush (fungal nappy rash)
- The rash is spreading beyond the nappy area (e.g., onto thighs or belly)
- Your baby seems unusually distressed, in pain, or develops a fever
What to Expect from a Visit
If the rash is due to fungal or bacterial infection, your GP may prescribe:
- An antifungal cream (for thrush-based rash)
- A mild steroid or antibacterial ointment (if there’s swelling or infection)
- Specific instructions on when to apply barrier cream vs. prescribed cream
In most cases, treatment is straightforward — and your baby will feel better within a few days.
Trust Your Instincts
If something doesn’t look right, or if you’re just unsure — that’s reason enough to ask. You know your baby best. And even if it turns out to be mild, there’s no harm in checking.
You’re not being dramatic. You’re being a good mum.
FAQs About Nappy Rash
1. What causes nappy rash during teething?
During teething, your baby’s drool increases and their poo can become more acidic. This change in stool composition can irritate the skin and lead to rash — even if you’re changing nappies often. Frequent, loose poos also leave less time for the skin to recover between changes.
2. Is nappy rash painful for babies?
Yes, it can be. Mild nappy rash may not bother your baby much, but severe rash — especially when the skin is broken or raw — can cause discomfort, stinging, or even pain when they wee or poo. You may notice your baby crying during nappy changes or resisting being touched in the sore area.
3. What’s the best treatment for severe nappy rash?
The best approach is to strip everything back:
• Use water and cotton wool only
• Apply a natural, fragrance-free barrier balm with zinc oxide
• Allow for nappy-free time
• Change nappies frequently (every 2 hours or after every poo)
In some cases, a GP-prescribed cream may be needed if there’s infection.
4. How often should I use barrier cream?
You can use a gentle barrier cream at every nappy change, especially when your baby has a rash or is prone to irritation. If using a prescribed treatment (like an antifungal), check with your GP about layering or alternating it with barrier balm.
5. Can cloth nappies help prevent nappy rash?
Cloth nappies can be helpful for some babies, as they’re free from certain chemicals found in disposables. However, they need to be changed more frequently to stay effective. Whichever nappy you use, the key is frequent changes and gentle care.
Summary
Nappy rash happens — even when you’re doing everything right. Whether your baby has a touch of redness or a sore, swollen rash that needs serious TLC, the most important thing is knowing how to tell the difference and respond with calm, gentle care.
Here’s what to remember:
- Most nappy rash is mild, caused by moisture, friction, or teething
- Severe nappy rash may include bleeding, swelling, or broken skin
- The key to healing is frequent changing, gentle cleaning, and a soothing, breathable barrier
- If things don’t improve, your GP or health visitor is there to help
- You are not alone — and you are not doing it wrong
At Matylda Baby, we created our balm for moments exactly like these — when your baby’s skin needs real protection, not perfume or filler. Our barrier balm is zinc-rich, fragrance-free, and deeply nourishing — made to soothe nappy rash naturally, even on sensitive or broken skin.
No stress. No harshness. Just thoughtful care for the skin you love most.
Leave a comment