Hi, The itchiness of scalp may be due to seborrheic dermatitis most probably. The lesions in thighs and buttocks may be related with this problem. Exact cause is not known. Yeast like pityriasis ovale may be responsible. Stress,worries and anxiety might exacerbate the disease. The hair loss can occur in seborrheic dermatitis. You consult dermatologist for firm diagnosis. He might give antifungal like ketoconazole,antihistaminic like levocetirizine and steroids in tappering dose. And he may advise to apply mild steroid lotion on scalp and cream on thigh and buttock lesions.. And shampoo the scalp with ketoconazole containing shampoo. Avoid stress and worries. Have patience for the good result. I hope you got my answer. Thanks. Dr. Ilyas Patel MD