Try Vaseline because it will seal it from it getting irritated.
My Dog Has Razor Burn On His Balls What Can I Use To Stop The Burning?
Stop letting him use a razor.....or have the vet make him eunich(unique).....
My vet told me to use regular diaper rash cream... But make sure to use an Elizabeth Collar (cone) for dogs head to stop from licking. Licking makes it worse, plus he'll lick all the cream off.