What is a good shampoo for pcos/hormonal/insulin induced hair loss?

I already have ketoconazole. I heard that is good for dht activitie on the scalp but I can't use it for every wash. I need something that is sensitive has no oils or extracts in it that can irritate my scalp and is lightly scented or fragrance free. i also have dry patches excema patches on my scalp.