Why Do Babies Get Diaper Rashes? And How to Treat Them

It's never a fun surprise to open your baby's diaper and find a red, bumpy rash, yet it's an inevitable part of caring for a tiny human. Where did it come from? Why does it look so angry? Should you be worried?

Luckily, most cases of diaper rash are mild and clear up with at-home treatments—but that doesn't make them any less unpleasant for both you and your uncomfortable baby. They seem to have a way of sneaking up when you least expect them, leaving you concerned and curious about how it could have been prevented.

So, what's the deal with diaper rashes? We're here to break down what they are, the causes, the treatments, and how to help prevent them from wreaking havoc on your baby's sensitive hind parts (and your sanity).

What Is a Diaper Rash?

We all have a general idea of what a diaper rash looks like, but maybe we don't know exactly what it is and why this happens.

"[A diaper rash] is an irritation of the skin caused in areas that come in contact with the diaper," explains Tyra Tennyson Francis, MD, a board-certified family physician who has practiced for over 10 years. "Stool and urine [along with the increased moisture that comes with them] in the diaper area act together to cause this irritation."

Diaper rashes are very common—at least half of all babies will get one at some point! There are four main types of diaper rashes, all of which can be identified by certain symptoms.

Irritant Dermatitis

Irritant dermatitis is the most common type of diaper rash (and one you have probably already seen once or twice). You will notice patches of pink or red skin that may appear mildly bumpy.

Since the skin in your baby's little creases and folds are more protected by the diaper, they are not usually affected.

Yeast Infection

Diaper rashes caused by a yeast infection causes shiny pink or red patches with noticeably sharp or defined edges. You might also notice pink bumps or pimples, sores, or cracking skin that oozes or bleeds (a sign to call the pediatrician). Unlike irritant dermatitis, the creases or groin folds may also be infected.

Bacterial Rash

Although less common than yeast infections, there are times when bacteria can cause a diaper rash. These infections are referred to as impetigo. When this occurs, you will see bright red skin around the anus, yellow crusting, or pimples. This can indicate a strep or staphylococcus ("staph") infection.

If you think your baby is suffering from a bacterial infection, it's important to reach out to your baby's pediatrician for confirmation and treatment.

Allergy Rash

Unlike the other three types of rashes, allergic rashes will typically only show up after exposure to certain products, including wipes, creams, or diapers. When this occurs, you will notice red, patchy areas. It is more likely to occur in babies with particularly sensitive skin.

What Causes a Diaper Rash?

Unfortunately for babies (and for you), there are a variety of reasons why a diaper rash might pop up. While some are preventable, others are simply out of your control.

Infrequent Diaper Changes

Sometimes your little one may sit in their diaper a little too long—it happens! (Life with kids can be a little hectic, after all). Unfortunately, if diaper changes do not happen frequently enough, it can lead to a diaper rash.

The longer their sensitive skin is exposed to urine and stool, the more likely you will see a rash pop up in the form of irritant dermatitis.

Diarrhea

When your child is experiencing a tummy issue like diarrhea, the chances of irritant dermatitis increase. Exposure to frequent bowel movements in the diaper can aggravate a baby's sensitive skin. In general, stool is much more irritating than urine.

Prolonged exposure to feces can also cause more severe issues such as small ulcers around the anus, which should immediately be examined by your baby's pediatrician.

Antibiotics

If your child is prescribed oral antibiotics, you may notice a rash due to a yeast infection. This is because antibiotics, although helpful in treating a bacterial infection, can also kill the healthy bacteria that help to keep yeast in balance.

When there is an overgrowth of yeast, it can cause an infection. Unfortunately, yeast thrives in warm or humid conditions, making your baby's diaper the perfect environment for growth.

Introduction to New Foods

When you introduce solids to your baby, the content of their stool can change, and they may begin to have more frequent bowel movements. This increase in poopy diapers can increase the likelihood that your infant will develop a diaper rash.

Along these lines, breastfed babies can also get diaper rashes in response to something the breastfeeding parent has eaten.

Using New Baby Products

This is the main cause of a contact allergic diaper rash. If you're trying out new wipes, ointments, or diapers, they have the potential to cause an allergic reaction. Once you identify the culprit, the rash may still last for another two to four weeks after you stop using it.

How to Treat Diaper Rash

Luckily, there are plenty of ways to relieve your baby's diaper rash. From over-the-counter (OTC) ointments to home remedies, your little one will be feeling better in no time.

OTC Treatments

There are several over-the-counter diaper rash creams and ointments available for quick, effective relief.

"You can [use] over-the-counter products such as Aquaphor or zinc oxide products like Desitin, Triple Paste, or Balmex," suggests Dr. Jonathan Jassey, DO, FAAP, a board-certified pediatrician. Depending on the type of rash, your child's healthcare provider may prescribe an antifungal or antibiotic cream.

For OTC creams, don't be afraid to really lather it on! In her blog, Nkeiruka Orajiaka, MBBS, a board-certified pediatrician and mother of three, refers to applying diaper rash cream as "frosting a cake." The more the better, especially for more severe cases.

The most important thing you can do to help a diaper rash is to keep the area as clean and dry as possible. If there is continued moisture, it is easier for the skin to get irritated and for yeast to multiply, and harder for the rash to heal.

How to Prevent Diaper Rash

While diaper rashes have a way of sneaking up on you and your baby, there are some preventative actions you can take to reduce how often they occur.

"I always recommend [putting] on either Aquaphor or zinc oxide creams with every diaper change to act as a good barrier so urine and stool don’t irritate the area," says Dr. Jassey. "Also, change diapers regularly so [they] aren’t sitting in urine or feces for a long time."

Dr. Francis reiterates the importance of over-the-counter ointments, adding that they contain zinc, which protects your baby's sensitive skin from irritation and promotes healing. You can also have "diaper-free time" as often as possible. (Depending on how brave you are!)

To avoid an allergic rash, try using a mild laundry detergent for your child's clothes and carefully observe any reactions to new products.

When to Call the Pediatrician

While most diaper rashes clear up with at-home treatment, others are a little more serious and require a trip to the pediatrician.

"If the rash isn't improving with at-home measures after a few days, definitely get in to see your pediatrician or family doctor," says Dr. Francis. "Some signs to look out for are any rapid spread, oozing, or draining of the rash. This could indicate the rash has been complicated by an infection." 

You should also contact your baby's pediatrician if you see pimples, blisters, or open sores in the diaper area or if your child seems dehydrated or has diarrhea with a fever.

A Word From Verywell

Although not fun to deal with, diaper rashes are incredibly common and usually clear up with some combination of creams, frequent diaper changes, and some diaper-free time. Making sure your little one doesn't sit in soiled diapers for too long and applying diaper rash cream after every change can help prevent the frequency in which rashes occur. If the rash is not clearing up within a few days or you notice any oozing, bleeding, blisters, pimples, fever, or sores, be sure to reach out to your baby's pediatrician.