Itch dry flaking Scalp

I have had a problem with dry (white), flaky, itching scalp for the last month or so.  It began as isolated spots of dry scalp but has escalated to extremely dry scalp with severe dandruff and flaking. The itching has increased and because I scratch my itching scalp, my hair is thinning and breaking.  I have tried scalp oils, but, it actually produces more flaking and dandruff.  Initially I was told by my hair stylist to use seabreeze on my scalp and avoid scratching, but my hair has never been this damaged and I'm very concerned.  Where do i start?  
  

[BhumikaMD]

Hi,
This could be seborrhoeic dermatitis. It is a skin disorder affecting the scalp, face, and trunk causing scaly, flaky, itchy, red skin. It particularly affects the sebum-gland rich areas of skin.
Side effects to inflammation may include temporary hair loss. If severe outbreaks are untreated for extended intervals, permanent hair loss may result, because of damage to hair follicles.
http://en.wikipedia.org/wiki/Seborrhoeic_dermatitis
Soaps and detergents such as sodium laureate sulfate may precipitate a flare-up, as they strip moisture from the top layers of the skin, and the drying property of these can cause flare-ups and may worsen the condition. Accordingly a suitable alternative should be used instead.
Among dermatologist recommended treatments are shampoos containing coal tar, ciclopiroxolamine, ketoconazole, selenium sulfide, or zinc pyrithione. For severe disease, keratolytics such as salicylic acid or coal tar preparations may be used to remove dense scale. Topical terbinafine solution (1%) has also been shown to be effective in the treatment of scalp seborrhoea,as may lotions containing alpha hydroxy acids or corticosteroids (such as fluocinolone acetonide). Pimecrolimus topical lotion is also sometimes prescribed.
It would be advisable to consult a skin specialist for his symptoms and a proper clinical examination if the symptoms persist.