Hi,
It 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 go untreated for long periods of time, permanent hair loss may result due to damaged hair follicles.
Expect two to six months before hair growth may resume.
Soaps and detergents such as sodium laureth 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.
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).
ref:http://en.wikipedia.org/wiki/Seborrhoeic_dermatitis
Also it's my right side of the scalp that sometimes has intense itchness, but only in certain spots, and sometimes it's the spots that I notice thinning.