Acid Diaper Rash: Treatment for Acid Butt Burn 81

After three boys, I thought I’d seen all a butt could turn out—from poop paintings to corn kernels—but when my fourth baby started getting weird acidic poop that literally seemed to eat her skin away, I was sort of baffled. Acid diaper rash was not something I had heard a lot about, but it happens, and it is horrible.
acid diaper rash

So, what exactly is acid diaper rash, and how do you spot it?

Acid diaper rash occurs when for one reason or another your baby’s poop becomes acidic in pH and literally burns the skin. For my baby, this was obvious by immediate bleeding rashes (when I knew she had just pooped). These bloody spots almost looked like she’d been poked repeatedly with a small pin and were only where the poop had touched.

Other types of diaper rash occur more frequently where the diaper touches or in skin creases, but this rash will be very red, possibly bleeding, inflamed skin only where the poop is touching, and it will be there no matter how quickly you change the diaper. I think that’s the biggest tell that a rash is acid-based, it happens almost instantly.

Next, the poop that accompanies acid diaper rash is often runny and looks poorly digested, like there are often still recognizable chunks of lunch. In babies that haven’t started solid foods, it just looks very runny and lacks the common seedy appearance. It may also have an off odor that just doesn’t smell like just poop, almost rancid.

What causes acid diaper rash or acidic poop?

Some babies can get acidic poop from high fruit intake or foods that are high in acid themselves such as tomato, but in my baby girl’s case, it was fructose sensitivity. It can take some diet exploration to pinpoint the cause of acidic poop, but it is almost always a dietary cause.

One of the easiest ways to track a food allergy or sensitivity is to keep a diet log. Note days the rash or acid poop occur and find common factors, then cut one factor at a time to see what works. As fructose sensitivity is a common culprit of acid diaper rash, I caution that not all fruit will get a reaction (bananas for instance are fine) and remember that high fructose corn syrup will also create an issue (“high fructose”).

How do you treat acid poop burns?

In this case, the most important thing is to identify the dietary issue causing the rash and eliminate it. The burns actually heal quite quickly as long as the acid poops stop. In the meantime, it can help to avoid baby wipes by using either a small squirt bottle or just a quick butt rinse in the tub. As it’s the wiping motion that tends to hurt, just dab dry afterwards.

The best diaper rash cream I found for this was the Triple Paste, though I would avoid applying anything but fresh air until the burns are no longer actively weeping. They, at least if your baby is changed quickly, are usually not very severe and it takes less than a day for the rash to look kind of scaly and red (this is like a thin scab over the burn) at that point it’s ok to use the cream and it will help things heal faster.

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Thank you for this article. I need to start tracking the diet. My son just turned one and this has only been a recent problem. My 4year old had/has it and I thought he was in the clear but it doesn’t appear so. It’s such a sad rash and like you said, instant to the stool touching the skin. Just a heads up for anyone suffering with this… my daughter ended up scared of pooping because it hurt her. I potty trained her at 2 just to get her out of diapers but accidents still lead to the rash so… Read more »


My nieces and nephew all suffered from a sensitivity to juice that seemed to make their urine and poop acidic. Their daycare and preschool centers weren’t exactly careful about withholding juice or watering it down. So these poor babies would come to my house with terrible raw rashes that made them scream in pain. I would set up a small luke warm bath and let them sit and soak clean for about 5-10mins. Then I, very lightly, pat the area dry and smoothed raw honey on it. I know it sounds weird, but honey is an amazing skin healer! It… Read more »

Lindsay M Julien

This is the first I’ve seen from any mom on this issue. My husband and I have been dealing with acid poop with my 2 year old daughter for a bout a year now (since she started solid foods). Through trial and air, just as you mentioned, I have found that it best to minimize the use of baby wipes (at least store bought one’s – I started making my own 100% organic, all natural baby wip es. Which seems like it would be difficult and expensive but it’s actually super quick, easy AND saves a ton of money as… Read more »


I fre my baby girl peaches today for the first time and boom acid …poor baby. I bet it was peaches.


Actually she had apples a couple of days ago so that could be it too or the carrots…

Stephenie McDaniel

My son just turned 3 a couple of weeks ago but he has had this issue a handful of times. Today we were swimming and he pooped but didn’t tell anyone and with the mixture of the acid poo and chlorine he now has a terrible diaper rash burn on his entire lower half (front and back) 🙁 I used scent free powder and he still jumped through the ceiling screaming in pain. He has been diaper free for a few hours now and he is complaining a lot less. Maybe this will be the potty training “fire under his… Read more »


Thank you 🙂


Thank you for this post! I’ve been Google searching my 19 month old’s symptoms, and I think this is it.