From the description, you might be having tinea cruris
. However seborrheic dermatitis and inverse psoriasis
should be ruled out. For the same you need to visit a dermatologist
I can see you have tried many creams for your concern but all of these contain steroids. Steroids reduce inflsmmation due to fungus but can lead to flare up of fungal infection
. Hence such creams are not advised without doctor's prescription.
Fungal infection can be treated by
Taking oral drug like fluconazole weekly
Application of plain antifungal cream like clotrimazole
, sertraconazole or terbinafine.
Take tabket cetirizine to reduce itch
Wear loose cotton clothes and underclothes
Dust the area with antifungal dusting powder in morning.
Hope that would help you. Take care