I Have Been Prescribed Timodine Cream For An Irritating Sweat

I have been prescribed Timodine cream for an irritating sweat rash,which manifests at the top of thighs in the groin area..When I first used the cream,the rash almost disappeared for a few days,but now when I apply Timodine,it returns with a vengeance,displaying red,itchy and irritating weals.Should I stop using it,as it seems to have stopped working,and is exacerbating the condition,instead of curing it,as far as I can see.