loosing hair on top and front of head and need help!

[newyorkman]

I am lossing hair on top and front of my hair. I have lot of itch and scalp irritation all over my head however i see hair loss mostly on top and front. I have been using nizoral and other shampoos for last few year . But of no use.
I also went to a dermatologist and he prescribed a amonia solution to get rid of the itch and white powdery thing in my hairs. The itch reduced however i can see my bald patch now. Is there anything I can do to stop hair loss ? I also want to stop the itch so that i don't scratch and make more hairs fall.
Any suggestions about any kind of treatment to get rid of hair loss and itch and get it growing back is welcomed. please help!