Hi, As you said you have scalp psoriasis...it may be relapsing and may for long time.I hope you might be taking regular and proper treatment of psoriasis from your dermatologist.Psoriasis is a chronic relapsing and autoimmune disease. Never take steroid as it might worsen psoriasis. I usually recommend cap acitretin 10 mg twice a day along with methotraxate 15 mg weekly in three devided doses 12 hourly. This may be taken for long time till good response. Blood tests may be done to monitor the treatment. Apply mild steroid lotion combined with salicylic acid on the scalp lesions. Regular and daily shampoo may be done with tar,salicyliacid and ketoconazole containing shampoo.Avoid stress and worries as that might worsen psoriasis. Avoid bad habit of smoking,tobacco and beverages. Avoid heavy combing of hairs of scalp,so that trauma may be avipoided,otherwise that might exacerbate the disease.Have patience for the good result.I hope you got my answer. Thanks. Dr. Ilyas Patel MD