The problem: red, sore skin under the nappy
At changing time the bottom is suddenly bright red, the baby cries as soon as the wipe touches the skin, and weeing stings (BVKJ). Sometimes the nappy smells strongly of ammonia (BIÖG). Nappy rash is one of the most common skin conditions in babies and toddlers (BVKJ); at least half of all babies get a sore bottom at some point (AAP). It most often affects babies between 3 and 15 months (DermNet).
The words "sore bottom" cover several different skin pictures. The table helps you tell them apart. It is based on specialist sources and does not replace a diagnosis; only an examination by your paediatrician can give you certainty.
| What you see | What it often is | What matters now |
|---|---|---|
| Pink to red areas where the nappy touches; the skin folds in the groin usually look normal | irritation from urine and stool, the most common form (AAP), (DermNet) | change often, dry, barrier paste, air |
| Redness and broken skin at the waistband or on the thighs | chafing from the nappy (DermNet) | nappy not too tight, right size |
| Shiny bright red areas with a sharp edge, small red dots or pustules around them, especially in the groin folds; often after antibiotics | nappy thrush caused by the yeast Candida (AAP), (DermNet) | paediatrician; no greasy ointments (BVKJ) |
| Bright red skin around the anus, yellow crusts, weeping areas or pus spots | possible bacterial infection (AAP) | paediatrician |
| Rash wherever a particular wipe or cream was used | rarely an allergy, for example to fragrances or preservatives (AAP) | leave the product out, ask the practice |
| Salmon-pink, flaking patches in the folds, plus scales on the head | infantile seborrhoeic dermatitis (DermNet) | practice; see Cradle cap or milk crust? |
Why the bottom gets sore – and what winter has to do with it
Wetness softens the skin. Urine and the closed nappy make the top layer of skin swell. Digestive enzymes and bile salts from the stool attack its fats and proteins; urine and stool together produce ammonia, and the skin's pH rises. On top of that, the nappy rubs with every movement (DermNet). Skin damaged in this way is more easily attacked by fungi and bacteria (BVKJ).
Solid food, diarrhoea, antibiotics. Breastfed babies get nappy rash less often because their stool has a lower pH. Once solid food starts, stools become more frequent and less acidic, and nappy rash occurs more often (DermNet). Diarrhoea and frequent poos encourage it, as do some medicines such as antibiotics or laxatives (NHS). Nappy thrush can develop after antibiotics (AAP).
Winter does not make it easier. In autumn and winter, babies and toddlers have more infections, with diarrhoea or with antibiotics, for example for an ear infection. And the most important house rule, letting air get to the bottom as often as possible, is harder to follow in a cool home. Under thick layers and tights it also gets warmer and damper inside the nappy.
Not an allergy to the nappy. Many parents suspect an allergy to the nappy material; according to studies this is very rare (BVKJ). Soap, bubble bath, fragranced or alcohol-containing wipes or poorly rinsed detergent are more often involved (NHS), (DermNet); more in Rash from laundry detergent.
The solution step by step
| Step | What you do | Why |
|---|---|---|
| Changing | Change full nappies straight away, always after a poo; newborns about every two hours, older babies every three to four hours. | The shorter urine and stool stay on the skin, the less it is irritated (BVKJ), (NHS). |
| Cleaning | With lukewarm water and a soft cloth; on broken skin, rinse with water from a squirt bottle instead of wiping. No oil, no soap, no baby lotion. | Oil stings on sore skin and encourages fungi (BIÖG); soap and lotions irritate (NHS); rinsing hurts less (AAP). |
| Wipes | If at all, fragrance-free and alcohol-free; while the bottom is sore, water and a cloth are better. | Fragrance and alcohol in wipes can irritate (NHS); preservatives can trigger allergies (DermNet); the German paediatricians' association tends to recommend water and a cotton cloth (BVKJ). |
| Drying | Pat dry carefully, especially in the skin folds, then let it air-dry briefly. | Damp skin softens further (BIÖG), (DermNet). |
| Protecting | Apply a fragrance-free barrier paste with zinc oxide or petroleum jelly; if it is still clean at the next change, do not rub it off but add more. | The paste keeps moisture away and sits like a shield between the skin and the nappy's contents (BIÖG), (AAP). |
| Air | Let your baby kick about without a nappy several times a day; in winter, warm the room first and use a washable mat. | Air on the skin is one of the most important measures (NHS), (BVKJ). |
| Nappy | A well-absorbing, well-fitting nappy, not too tight; no plastic overpants. With cloth nappies, change liners often or use disposables until the rash has settled. | Barrier creams and modern nappies keep moisture and irritants away from the skin (Blume-Peytavi and Kanti 2018); tight nappies and plastic rub and trap moisture (NHS), (AAP). |
| Bathing | A daily bath is fine, but not more than twice a day; without bubble bath. | A daily bath removes residue, washing too much dries the skin out (NHS). |
| Hygiene | Wash your hands before and after every nappy change. | This matters especially with nappy thrush (AAP), (DermNet). |
Thin or thick? The recommendations differ here: the BIÖG and the British health service speak of a thin layer (BIÖG), (NHS), while the American Academy of Pediatrics advises a thick layer on irritated skin (AAP). What matters is that the irritated skin is covered and the paste is not rubbed off at every change.
What helps – and what doesn't
| Measure | Assessment |
|---|---|
| Zinc paste or barrier cream with zinc oxide, fragrance-free | helps as a protective layer (AAP); the brand matters less than the ingredients |
| Oil for cleaning | no: it stings on sore skin and encourages fungi (BIÖG) |
| Greasy ointments with nappy thrush | no: greasy ointments should not be used when fungi are involved (BVKJ) |
| Powder | no talcum powder on a sore bottom (NHS) |
| Antiseptic creams or non-prescription antibiotic ointments | no: they can irritate the skin further (AAP), (NHS) |
| A few drops of breast milk | named as a tried-and-tested measure by the BIÖG and the paediatricians' association (BIÖG), (BVKJ); there are few studies |
| Black tea | we have not found any studies in babies, and the specialist sources do not mention it. Damp compresses add extra wetness to the bottom; dryness matters more |
| Untreated sheep's wool with wool wax, as sold for sore bottoms | we have not found any studies. It contains wool wax (lanolin), to which some people are allergic; more in Lanolin or beeswax |
| Steroid or antifungal cream | only if prescribed by your paediatrician, and only for as long as prescribed (AAP); strong steroid creams do not belong on a baby's bottom (DermNet) |
Common mistakes
The most common mistake is wiping hard at every change and rubbing off all the barrier paste even though it is still clean; that irritates the sore skin anew each time. Second, the bottom is cleaned with oil or oiled thickly, even though oil stings on sore skin and encourages fungi. Third, nappy thrush is treated for weeks with a greasy nappy ointment because it looks like ordinary nappy rash. Fourth, fragranced wipes, lotions and powders are used. Fifth, the nappy brand is switched on suspicion instead of changing more often. And sixth, parents wait even though the bottom is not better after two or three days of consistent care.
When to seek medical advice?
Call 112 if your baby has a fever and spots that do not fade when you press a glass against them, if they do not want to feed, are floppy, hardly respond or are difficult to wake, have a high-pitched, unusual cry, feel stiff or have a bulging soft spot on the head (NHS: Meningitis). That has nothing to do with nappy rash, but these are signs that count with any rash and fever.
See your paediatrician if
- your baby has a fever or seems very restless and unhappy (NHS), (AAP),
- spots, blisters, pus-filled pustules, weeping or crusted areas or peeling skin appear (AAP),
- shiny red areas with small dots at the edge develop, especially during or after a course of antibiotics; that points to nappy thrush (AAP), (BIÖG),
- the bottom is especially painful, which can indicate a deeper inflammation of the skin (AAP),
- the rash spreads, gets worse or is not better after two to three days of good care (AAP), (NHS),
- the rash keeps coming back or also appears elsewhere; sometimes a different skin condition is behind it (BVKJ).
Seeing the practice early prevents the rash from spreading further (BVKJ). Whether bacteria or fungi are involved can only be determined by the paediatrician.
Frequently asked questions
Nappy rash or nappy thrush: how can I tell the difference?
Plain nappy rash reddens the skin where the nappy sits and usually spares the groin folds. Nappy thrush is shiny bright red, sharply edged, sits especially in the folds and has small dots or pustules at the edge (AAP). Your paediatrician can tell for certain.
Which cream helps with a sore bottom?
For care, a fragrance-free barrier paste with zinc oxide or petroleum jelly (AAP). If a fungal or other infection is involved, the practice will prescribe a suitable cream; greasy ointments are then unsuitable (BVKJ).
How long does nappy rash last?
With frequent changing, drying, barrier paste and air, it usually gets better within a few days. If it is not better after two to three days, take your baby to the practice (AAP).
Does teething cause nappy rash?
Opinions differ. The American Academy of Pediatrics names teething as a possible reason because the baby swallows more saliva (AAP). In a study of 125 babies, however, rashes other than on the face were not linked to teeth coming through (Macknin et al. 2000). If your baby is ill, do not simply put it down to teething.
What if the nappy rash does not go away?
After two to three days of consistent care without improvement, see your paediatrician. Nappy thrush, a bacterial infection or another skin condition may be behind it (DermNet).
Is nappy thrush contagious?
The yeast lives naturally in the gut (AAP). Wash your hands before and after changing and use separate towels for the baby, especially while the bottom is affected.
What role does diet play?
Nappy rash becomes more common once solid food starts (DermNet). If you notice it gets worse after certain foods such as orange juice, you can leave them out for a while (DermNet).
Do adults get nappy rash?
Yes, with incontinence; the technical term is incontinence-associated dermatitis (DermNet). There too it is about cleansing and skin protection; according to a Cochrane review, it is not yet well researched which products prevent it best (Graham et al. 2025). For sore skin in skin folds, see Sore skin in skin folds (intertrigo).
At forpeople
We have no suitable product for a baby's bottom and do not recommend one here. What helps is a fragrance-free barrier paste with zinc oxide from the pharmacy or chemist, plus water, a soft cloth and air. Our creams, balms and oils are not intended for baby skin: many contain essential oils, our almond oil is a nut oil, and greasy ointments do not belong on the bottom if nappy thrush is suspected.
Questions about dry skin elsewhere on the body are answered in Dry skin in babies.
More on this: Heat rash in babies · Cradle cap or milk crust? · Dry skin or atopic eczema? · Impetigo in children · Sore nipples when breastfeeding
Sources
- Bundesinstitut für Öffentliche Gesundheit (BIÖG): Milchschorf, Kopfgneis und Windelausschlag – was tun bei Hautproblemen? kindergesundheit-info.de, as of 20 May 2026. Accessed 30 Oct 2026. kindergesundheit-info.de
- Berufsverband der Kinder- und Jugendärzt*innen (BVKJ): Windeldermatitis – Windelsoor. kinderaerzte-im-netz.de, last updated 18 Sep 2017. Accessed 30 Oct 2026. kinderaerzte-im-netz.de
- DermNet: Napkin dermatitis. Oakley A (1997), updated by Gomez J, February 2017. Accessed 30 Oct 2026. dermnetnz.org/topics/napkin-dermatitis
- NHS: Nappy rash. Last reviewed 28 Aug 2026. Accessed 30 Oct 2026. nhs.uk/baby/caring-for-a-newborn/nappy-rash
- American Academy of Pediatrics (AAP), Section on Dermatology; Polcari I: Common Diaper Rashes & Treatments. HealthyChildren.org, last updated 18 Dec 2024. Accessed 30 Oct 2026. healthychildren.org
- Blume-Peytavi U, Kanti V (2018): Prevention and treatment of diaper dermatitis. Pediatric Dermatology 35(Suppl 1): s19–s23. https://doi.org/10.1111/pde.13495
- Macknin ML, Piedmonte M, Jacobs J, Skibinski C (2000): Symptoms associated with infant teething: a prospective study. Pediatrics 105(4 Pt 1): 747–752. https://doi.org/10.1542/peds.105.4.747
- Graham T, Beeckman D, Kottner J, Fader M, Fiorentino F, Fitzpatrick JM et al. (2025): Skin cleansers and leave-on product interventions for preventing incontinence-associated dermatitis in adults. Cochrane Database of Systematic Reviews 7: CD011627. https://doi.org/10.1002/14651858.CD011627.pub3
- NHS: Meningitis. Last reviewed 12 Jun 2026. Accessed 30 Oct 2026. nhs.uk/conditions/meningitis
