Hello,
For such symptoms which can be due to severe dandruff or adult cradle cap, eat a healthy diet. You can also take vit B6 and vit A and E which are good for hair and skin. Try medicated shampoos for dandruff. There are a number of over-the-counter shampoos available that can help. The most effective ingredients -- antimicrobials -- to look for are zinc pyridinethione, selenium sulfide, sulfur and ketoconazole (also available by prescription). If your hair is colored, don't use products with selenium sulfide or sulfur.
If the symptoms persist please consult a trichologist for the confirmatory diagnosis and treatment.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
My family had the same problem. By accident, we cured the problem while trying to fix other problems. We went on a gluten free diet (foods that contain wheat, barley, rye and possibly oats) for other reasons, and realized we all got scalp relief - no more itching, crusting, etc. Food intolerances, like gluten and cow's milk foods, when not digested, allow yeast to overgrow. It causes yeast overgrowth in and on the body. Of course, sugar is another promoter of yeast. But the gluten free diet relieved all of our scalps about 95%.
Only minimal symptoms left behind. We sometimes use Nizoral 2% shampoo (prescription strength) - you leave it on for 3-5 minutes in the shower and rinse. It is an antifungal shampoo. The diet sounds like a strange cure, but it worked for us. Hope it helps you. You have to stick to the diet 100% for it to be effective. Good luck.