Sounds like you are having Seborrhoeic Dermatitis
and there is a good treatment available for that.
1:start applying Nizoral
AD shampoo every alternate day,while having a shower apply the shampoo to wet hair,rinse well,make a lather and leave it for 5-10 minutes in the scalp
,and then wash it.Repeat the same thing for 3-4 weeks and I serve ye effects.
2- apply Betonil lotion to the scalp every other night to reduce the itch and inflammation and to lessen the flakes,again for a month.
one cap morning and evening,it's a very good anti oxidant.
I hope this will help you out but if not then please see your dermatologist
All the best.