itchy scalp and skin no rashitchy bumps on skin and scalpitchy scalp symptoms diseaseitchy scalp autoimmune diseasecauses of dandruff and itchy scalpitchy scalp menopausediabetes and itchy scalpitchy scaly scalp causescauses of itchy scalp and neckitchy rashes on scalpwebmd itchy scalpconstant itchy scalp no dandruff