Both our kids had terrible diaper rash due to pretty bad diarrhea after birth. We tried everything (Dr. B's, desitin, Vaseline). Nothing seemed to help until they grew out of it after a few months. We even tried calmoseptine, which worked to a point but was hard to spread and clean off and has a scent to it.
Then I discovered this with my second child. It's a lifesaver. Easy to apply, cleans off very well which is a plus for the 3AM diaper changes. Stays in place. Actually helps heal the rash/exposed raw areas instead of just being a barrier. Diaper rash healed within a week and we use this religiously now, especially when either of my young ones gets a diarrhea illness.