I have a really annoying problem - I have dandruff that doesn't shed and come loose. The skin of my scalp literally dies in chunks but doesn't fall off like normal dandruff. I have to scrape it off every single day or else I'm plagued with itching. Some of it is in the form of flakes, others are scales, ranging in color from white to gray to yellow. Is this a medical problem that's been recognized before or am I the first victim of a new dandruff disease? If anyone can give me any help or hope at all, I'd appreciate it. Thank you.

You either have severe dandruff, or psoriasis.
It would be best to consult a specialist, who might prescribe a good antidandruff shampoo, with antifungul medication in it, as dandruff is caused by the reaction of your body to the excretion products of pytirosporum ovale, a fungus.
If the skin on your head is red and pinpoint bleeding is visible when you take off the dead skin, there is the possibility that you are suffering from psoriasis, which is a condition, that can affect other parts of your body also.
If you have normal dandruff and are also suffering from scaling and redness on the sides of the nose and between the eyebrows, or itching in the ears, you might want to try washing your face and ears with anti-dandruff shampoo too.
Best of luck, fj

Use NIZORAL shampoo this is the commonly used & recommended anti-dandruff shampoo. Or scrub your scalp with lemon or fresh lemon juice.

Try a shampoo with coal tar like lphosyl, t-gel etc.

I had the same problem before. Use good old fashioned head and shoulders shampoo twice a day until it clears, then you can keep it at bay by using it once or twice a week.