Try Lotrimin cream or tea tree oil.
Do you have hemorrhoids? You may have constant moisture there if you have a condition like hemorrhoids. If using an antifungal cream for the full course doesn't fix it, try a diaper rash cream. I would avoid hydrocortisone.
Hemp Oil works great on keester itch, as long as it's viral.
Apply topically- it will sting like heck and then you'll be better the next day.
You have to use oil made from blighted leaves for it to work in this manner.
Try neem oil. Undisputed best at skin irritations.
Thank you guys for ur suggestions...
I tried Hydro-cortisone so many times and indeed it didn't work. It's really getting frustrating. Thanks for your suggestion.