I have thyroid problems and my hair is thinning like crazy?

What would be a good product for thinning and falling hair, each time i wash my hair its falls, i have dry hair and i do not know what product to use, i am 44 four and the doctor told me is due to my thyroid problem. i hear about so much products but i do not know what to choose any body out there with my problem? and is always itching even when i wash it and i use oil and conditioners in my hair.