Nappy Rash vs Eczema: How to Tell the Difference

Last reviewed: 9 August 2026

A rash on the bottom and a rash on the face are usually two different stories. Nappy rash and eczema are the two most common in the first year, and they can look alike enough to throw most parents at the first glance. They behave differently though. Where the rash sits, what it does over a few days, and whether it itches will tell you most of what you need to know before you talk to your GP.

This guide walks through both side by side, with the comparison table the centrepiece. The aim is practical: enough to triage at home, and enough to give your GP a clear picture if you do book in.

The short answer

Location is the biggest tell. Nappy rash stays in the area covered by a nappy. Eczema usually shows up on the face, scalp, and the outsides of the arms and legs, with the nappy area spared. The second tell is what each rash does with basic care: nappy rash clears within a week with frequent changes and a thick barrier; eczema does not.

The rest of this guide works through the detail: what each rash looks like, the side-by-side table for the change-table moment, the situations where the answer isn't clean, and the signs that mean a GP, the emergency department or an ambulance rather than another day of watching.

What nappy rash looks like and why it happens

Nappy rash is irritant contact dermatitis in the nappy area. The skin gets wet, sits against urine and faeces, rubs against the nappy, and eventually inflames. The Royal Children's Hospital Melbourne and the Australasian College of Dermatologists both describe the typical pattern: a widespread red rash on the convex skin surfaces in contact with the nappy, with the deep groin folds usually spared. Raising Children Network puts the practical reason plainly: the skin folds aren't usually affected because wee doesn't get into them.

Nappy rash sits in the area the nappy covers. Bottom, thighs, the bits around the front. It's the convex skin that takes the rub. The deep skin creases usually look fine.

That's the giveaway. If the creases are clear and the high spots are red, you're looking at the everyday irritant rash that most babies get at some point. It is one of the most common skin problems babies get in the first year.

It often comes on quickly. Common starters are a poo that sat too long in the nappy, a stretch of less-frequent changes, a course of antibiotics that changed the gut, a tummy bug, or a new food that loosened things up. Sore but not itchy is the usual picture. With frequent changes, gentle cleansing using lukewarm water and cotton wool or a soft cloth, plenty of nappy-off time, and a thick zinc-based barrier cream at every change, simple nappy rash settles in two to five days.

What eczema looks like and why it happens

Eczema, also called atopic dermatitis, is a chronic skin condition. The skin barrier doesn't hold moisture the way most skin does, and the immune system reacts more strongly to everyday things. It's partly inherited.

According to RCH, eczema affects around 30% of children and often starts before twelve months. ASCIA's consumer information puts onset in the first six months of life for most babies who develop infantile eczema.

The distribution is the second big clue. RCH describes the classic pattern in babies under eighteen months as dry, red patches on the cheeks, forehead, and scalp first, then the trunk and the outside of the arms and legs as the baby starts to move more. The nappy area is usually spared because the occluded environment keeps the skin moist, and dryness is one of the things that drives eczema.

Eczema itches. That's the feature that tells you most. A baby with nappy rash is uncomfortable, but an eczema flare makes them try to rub their face on whatever is nearest, scratch at their cheeks with their hands, and wake more often.

The skin looks dry and scaly rather than shiny, and on darker skin it may not look red at all. The Australasian College of Dermatologists and DermNet NZ both note that on darker skin, eczema can show as grey, purple, or dark brown patches, or as thickened scaly skin with little colour change at all.

The other big clue sits in the family. If you, your partner, or other family members have eczema, asthma, or hay fever, the chance of eczema in your baby goes up. RCH calls this a genetic tendency called "atopy".

Side by side: nappy rash vs eczema

The comparison table below pulls the differences into one place. It is the fastest way to triage what you are looking at on the change table. If two or three rows in the same column match what you are seeing, that points strongly one way, and your GP can confirm it. Any sign in the section on when to get help comes first.

If the rash is in the nappy area, has spared the creases, isn't particularly itchy, and started in the last few days, it's almost certainly nappy rash. If the rash is on the face or scalp, is dry and scaly, is itchy enough that your baby is rubbing at it, and there is eczema or asthma or hay fever elsewhere in the family, it's almost certainly eczema. The middle ground is real, and that is what the next sections are for.

Can a baby have both at the same time

Yes. They sit in different areas, so a baby with eczema on the cheeks can also have a separate irritant rash on the bottom. Better Health Channel notes that babies with cradle cap or facial eczema may be more likely to develop nappy rash, which makes sense given more sensitive skin overall.

The trap is using one approach for the other. A thick zinc barrier on facial eczema doesn't help and can make the skin feel worse. Moisturiser on a wet, broken-down nappy area doesn't act as a barrier and can sting.

Each rash gets its own approach, in its own area. If you have both, manage the nappy area with frequent changes, gentle cleansing, air time, and a thick barrier, and manage the eczema with moisturiser and the GP's eczema plan.

Two other rashes can sit alongside or look like the simple ones. A bright red rash sitting inside the creases with small dots or pustules outside the main edge is the pattern of candida (yeast); a non-itchy salmon-pink rash on the scalp, face, or body folds is closer to seborrhoeic dermatitis (the cousin of cradle cap). Heat rash can flare in the warmer months too. Your GP will rule these in or out; if a rash doesn't behave the way the table above describes, don't guess.

When to get help: 000, hospital or GP

Some signs need an ambulance or the emergency department straight away. Some need a doctor as soon as possible, and some a GP today. Others are worth a GP visit this week. If you're not sure which group your baby fits, treat it as the more urgent one, and call 000 if your baby seems very unwell.

There's a difference between watch and adjust and see someone today. A bit of redness on the bottom that you've just spotted, on a baby who's otherwise themselves, watch and step up the basics for a couple of days. A rash that has spread, that's a call to a doctor as soon as possible, and honey-coloured crusts or bleeding need a GP today; a fever or blisters in a baby under three months mean the emergency department straight away, and a baby with a rash who seems unwell in any way means 000. Anywhere in between, not improving after a few days, book in with your GP this week. Eczema itch that is unsettling sleep or feeds, in a baby who is otherwise alert and responsive, needs a doctor as soon as possible, the same day. If you just have a feeling something isn't right, see a doctor today rather than waiting.

The Australian sources line up on the timing. RCH and Raising Children Network both advise seeing a GP if a nappy rash hasn't improved by about a week of correct care. For suspected eczema, see your GP for the diagnosis and an Eczema Action Plan, rather than trying to settle a chronic skin condition with shop-bought creams alone.

Call 000 or go straight to the emergency department

• A fever with any of these: drowsy or hard to wake, trouble breathing, a stiff neck, a seizure, looking blue or very pale, or a rash that does not fade when you press on it.
• A rash that does not fade when you press on it and is spreading, or comes with a fever or a baby who seems unwell in any way. In a baby under three months, call 000 too if it looks like purple bruises.
• Blue or grey lips, tongue or face, or skin on your baby's body that looks pale, blotchy, grey or blue. Don't wait to see whether warming helps. On darker skin the change can look grey or white, so check the lips, tongue and nail beds.
• A baby who is floppy, drowsy, hard to wake or not feeding, has trouble breathing or a seizure, or who you feel is very unwell.

Go to the emergency department now

• A fever of 38°C or higher in a baby under three months, even if they seem otherwise well. healthdirect advises taking a baby under 3 months with a fever to the nearest hospital emergency department immediately. Do not wait for a GP appointment.
• A rash that does not fade when you press the side of a clear glass firmly against it (a non-blanching rash) in a baby under three months, even with no fever and a baby who seems well. In an older baby, a purple rash that looks like bruising and does not fade needs the emergency department too.
• Blisters, or a cluster of small fluid-filled spots, in the nappy area or anywhere else on a baby under three months.
• If your baby has eczema and gets a cluster of small blisters or punched-out sores, at any age and especially with a fever, go to the emergency department straight away. Do not wait for a GP appointment. This can be eczema herpeticum, a cold sore virus infection of eczema skin. If your baby is floppy, drowsy, hard to wake or seems very unwell, call 000. Don't let anyone with a cold sore kiss your baby.

See a doctor as soon as possible

These need a doctor within hours, the same day, rather than a routine booking.

• A fever with a new rash in a baby over three months, or a baby who is getting sicker rather than better.
• A rash that does not fade when you press on it in a baby over three months who seems well and has no fever.
• Blisters in a baby over three months who doesn't have eczema.
• A rash that is spreading fast.
• Any diarrhoea in a baby under six months.
• Eczema that is keeping your baby awake, or making them unsettled or feed poorly because of the itch, when they are otherwise alert and responsive.

If no GP can see your baby within hours, go to the emergency department. NURSE-ON-CALL (1300 60 60 24 in Victoria) or healthdirect (1800 022 222) can help you work out where to go, but if a sign from the 000 or emergency department lists is present, act on that first.

See a GP today

• Weeping, pus, or honey-coloured crusts.
• Bleeding or open sores.

Book a GP visit this week

• A nappy rash hasn't improved after about a week of careful four-pillar care (frequent changes, gentle cleaning, air time, thick barrier cream).
• A rash keeps coming back.
• You think the rash on your baby's face, scalp, or body might be eczema.
• A bright red rash that gets into the creases with small spots dotted beyond the main patch, which can be thrush (candida).

A GP sees nappy rash and eczema every week. The visit will be quicker and the advice more accurate if you can describe where the rash is, when it started, whether it itches, and what you've already tried. A clear photo at the worst point is worth taking too, especially with skin that calms down before the appointment.

What to do while waiting for the GP

For the nappy area, stick with the four pillars. Frequent changes, gentle cleansing with lukewarm water and cotton wool or a soft cloth, as much nappy-off time as you can manage, and a thick zinc-based barrier cream at every change. Apply it thick enough that you can still see some of it the next time you open the nappy. Raising Children Network is clear on that thickness cue.

For eczema patches on the face, scalp, or body, the routine is different. Use a fragrance-free moisturiser (emollient), not a barrier cream. Keep baths short and lukewarm, and skip soaps and bubble baths.

Dress your baby in soft cotton rather than wool or synthetics, and keep the room cool. RCH points out that heat is the most common eczema trigger in babies. If your GP has prescribed a steroid cream as part of an eczema plan, use it as directed during flares; the Australian clinical position from RCH and the Australasian College of Dermatologists is that prescribed steroid creams are safe when used as directed and tend to be underused rather than overused. Don't start a new steroid cream without GP advice.

Don't assume the wrong diagnosis. The classic mistake is to put a steroid cream on a rash in the nappy area that is actually candida (which spreads with steroids alone), or to slather a thick zinc barrier on facial eczema (which won't address the dryness underneath). When the rash isn't where you expect it or isn't behaving the way the table above describes, get the GP's eyes on it before you change tack.

While the skin is sore, clean the nappy area with lukewarm water and cotton wool or a soft cotton cloth rather than a wipe. The Royal Children's Hospital is direct on this: baby wipes can be very irritating and should not be used while a nappy rash is going. Once the rash has settled, a fragrance-free, alcohol-free wipe is fine for routine changes on healthy skin. Plain cotton clothing and a plain laundry detergent are the simplest choices for everything else, and it is worth looking for independent skin-safety testing on the label rather than marketing claims.