For us grown-ups, life’s two yucky inevitabilities are death and taxes. But for babies (and their parents) those inevitabilities are poo…and diaper rashes.

Diaper rash is nothing to feel bad about (okay, your baby may disagree about that), but they are pretty common considering the irritation that can come from sitting in a diaper wet with pee or acidic baby poo for a few minutes. Fortunately, there are a few simple things you can do to treat diaper rashes…and even stop them before they happen.

What causes diaper rashes?

This is not too big a mystery: Pee and poo are irritating to baby’s sensitive private parts. Baby poop is pretty acidic (especially in the first weeks) and pee that sits too long turns into ammonia, which is also very irritating. Not surprisingly, diarrhea is a common culprit for bringing on some fast and furious rashes.

Other possible diaper rash-triggers are:

  • Diet: Acidic eats—like oranges, strawberries, and tomatoes—can make poop irritating.

  • Chafing: A too-tight diaper or snug clothing can rub and cause rashes.

  • Sensitivity: Chemicals in laundry detergent, baby wipes, and even diapers themselves can cause irritation.

Less common causes for diaper rash are bacterial, fungal, and yeast infections. Bacteria and fungi love a moist jungle…and that makes your baby’s loaded diaper a paradise for those creepy crawlies! Yeast grows in the absence of “good” bacteria and often makes its appearance when a baby or breastfeeding parent takes antibiotics, which kill the protective bacteria, allowing the yeast to flourish.  

All that means you may have to become a sharp-eyed detective to figure out the clues!

What does a normal diaper rash look like?

Diaper rashes look red and angry! They typically appear as bright pink or red patches on the genitals, buttocks, thighs, or belly. They may look shiny or have small, red bumps and slightly flaky skin…they are a little sore and irritated…and a bit uncomfortable.

As you would imagine, there are a few warning signs that will tip you off when a garden variety rash turns into a four-alarm fire. If you see open sores, pus-filled blisters or yellow crusting in the diaper rash, your baby may need prescription medication. Call your pediatrician if the rash keeps getting worse, is very painful, or is accompanied by a fever.

How to Treat Diaper Rash

Gently clean and dry the area, then apply an over-the-counter diaper cream to the rash. These creams act as a barrier between a wet diaper and your baby’s skin. Some are petroleum-jelly-based and greasy while others are zinc-oxide-based and pasty. Experiment to see what works best for your baby. You don’t have to wash the cream off between diaper changes (unless it’s gotten poopy). Just layer cream on as needed.

You could also use aloe, which has antimicrobial and anti-inflammatory properties. Clean the leaf with alcohol and squeeze out some of the gel to apply it. For a super fiery rash, you may need a bit of cortisone (look for formulas with 1% cortisone) to tamp down inflammation.

There’s an old medical saying that “if it’s dry, wet it, and if it’s wet, dry it,” which ends up being true when it comes to diaper rashes. Since friction can cause a rash, restoring the moisture barrier with cream or gel (as described above) can help. On the flip side, too much moisture can cause a rash, so if that’s the case, you can sprinkle a tiny bit of corn starch to dry the area. This is a better alternative to baby powders, which can be dangerous if inhaled. Worse, talc-based baby powders may be linked to certain cancers. (In fact, Johnson & Johnson will stop selling talc-based baby powder globally in 2023.)

How to Prevent Diaper Rash

It’s hard to prevent diaper rashes 100% of the time, but you can make them less likely to occur by taking the following steps:

  • Change your baby’s diapers often—every two to three hours and whenever you notice a bowel movement has occurred. (Learn more about how many diapers babies and toddlers use.)

  • Use the most absorbent diaper you can find to wick away moisture from Baby’s skin, especially overnight. If you’re using cloth diapers, consider temporarily switching to a disposable diaper until the rash clears.

  • Choose alcohol-free and fragrance-free baby wipes or try using a washcloth moistened with warm water to clean Baby’s tender skin during diaper changes. If the diaper rash hurts, you could apply water with a spray bottle to avoid contact.

  • Apply a thick layer of barrier cream to rash-prone areas as a preventative measure. Use a cream with zinc oxide and/or petroleum jelly.

  • Let your baby’s diaper area air dry before putting on a new diaper.

  • Build some diaper-free time into each day. For instance, tummy time could be naked time—just lay down a washable blanket in case of accidents. The more time you can give your baby without a diaper on, the better when it comes to preventing rashes.

  • Keep the area clean with a daily bath using a gentle, fragrance-free cleanser. (Tips on how to give littles ones a bath.)

  • Make sure diapers and bodysuits aren’t too tight so chafing doesn’t occur. You might even try sizing up.

  • Tune into Baby's diet. Different solid foods may affect your baby’s rashes. Avoid foods that seem to make rashes worse.

  • Scrub your own hands well after diaper changes to avoid spreading bacteria.

What about cloth diapers?

Well, there’s no question: Paper diapers cannot be recycled, but cloth can…so score 1 point for the cloth alternative. From an environmental point of view, they don’t pile up in city landfills. On the other hand, they do use much more water resources, diaper services to truck them back and forth, and there may be more of a hygiene issue—while most diaper changes are just pee, storing the poopy diapers can be a hassle and some doctors believe they are more likely leak and cause diaper rash. (Learn more about cloth diapering.)


More diaper know-how:

About Dr. Harvey Karp

Dr. Harvey Karp, one of America’s most trusted pediatricians, is the founder of Happiest Baby and the inventor of the groundbreaking SNOO Smart Sleeper. After years of treating patients in Los Angeles, Dr. Karp vaulted to global prominence with the release of the bestselling Happiest Baby on the Block and Happiest Toddler on the Block. His celebrated books and videos have since become standard pediatric practice, translated into more than 20 languages and have helped millions of parents. Dr. Karp’s landmark methods, including the 5 S’s for soothing babies, guide parents to understand and nurture their children and relieve stressful issues, like new-parent exhaustion, infant crying, and toddler tantrums.

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Disclaimer: The information on our site is NOT medical advice for any specific person or condition. It is only meant as general information. If you have any medical questions and concerns about your child or yourself, please contact your health provider.