It could be die-off. Are you taking anything for die-off?
Also, have you tried using coconut oil topically on the rashes (in addition to taking it internally)? It’s a great moisturizer, which should make the dryness more comfortable, and it’ll help boost the antifungal effect to that part of the body. The simple act of massaging the oil into your skin will also stimulate circulation of both blood and lymphatic fluid, which is good for skin in general.