Babies have pretty sensitive skin, and being in wet or poopy diapers can be rough on them. Urine normally contains some ammonia which is harsh on the skin. Standard (not infected) diaper rash is mainly a reaction to the ammonia in the urine. Having diarrhea can also lead to irritation and rashes, mostly on the bottom. The best treatment for this type of diaper rash is to protect the skin from contact with urine (or watery diarrhea) by using a water-proof barrier such as a cream or paste. There are several products for this purpose that you can buy at the drugstore, but the most water-proof substance is Crisco since it is pure fat and cannot mix with water. Just get the kind you can cook with, in the cooking section of the grocery store. Crisco is much cheaper than the drugstore products, and actually works much better.
Apply a thick layer of Crisco on the red or sore areas of the diaper rash each time you change your baby’s diaper.
It also helps to leave off the diaper and expose the wet raw skin to air, allowing it to dry out. This can be done every 3-4 hours during the day for 5-10 minutes at a time. Then apply Crisco again and put on a fresh diaper if needed. Be prepared for your baby to pee (or poop) while the diaper is off, so choose an appropriate place to do this.
Most diaper rash is the ammonia type, and does not involve bacteria or yeast infection. So no antibiotic is needed. In fact, antibiotics often CAUSE diaper ashes. That’s because the antibiotic kills the normal bacteria that live in your body and which protect you from yeast infections.
Be on the lookout for yeast rashes if your baby has to be on antibiotics for other reasons, like an ear infection or strep throat. This type of diaper rash has a very different appearance than ammonia rash. The ammonia rash is mainly in areas of the skin exposed to wet urine-soaked diapers, but it spares the creases of the skin which are tucked away and can’t touch the diaper.
Yeast rashes are the opposite. They are mainly in the skin creases but can spread to the entire diaper area eventually. The treatment of yeast rashes involves using an anti-yeast medication, applied to the skin usually about 3 times a day. It also helps the skin to heal faster by applying Crisco to the skin on top of the yeast cream. Yeast grows in warm wet areas, so keeping moisture away, and allowing the skin to dry will also prevent yeast growth.
(Disclaimer: I’m not sponsored by Crisco)