### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
Hi! I have a friend who was diagnosed with psoriasis. There is a red rash covering his whole body in patches. The rash is round, red, and has very thick raised scaly areas that are more cream to yellow in color. He says these areas itch, and feels like pins pricking his skin. His doctor prescribed him topical medicine that has not improved the areas at all. These areas also include the palms of his hands and soles of both feet. Onset was very sudden. He does have a hx of blue dye allergies, but this looks different.

### output:

Hello and welcome to Chat Doctor Psoriasis presents as well-defined, thick scaly plaques mainly involving the scalp, and extensor surfaces like elbow, knee, lower back unlike extensive psoriasis disease for which both oral and topical treatment is required, for limited disease topical treatment alone is effective. However, for extensive disease systemic treatment with oral immunosuppresses like methotrexate, cyclosporin, Phototherapy (PVA), Biologics etc. may be required for disease control. Specific topical treatment options for psoriasis plaques are topical steroid with or without salicylic acid, topical vitamin D analogues like calcitriol, calcipotriene etc. These are available in ointment form for plaques involving the body and in lotion form for scalp psoriasis. Topical therapy may be combines with oral/systemic therapy for widespread/extensive disease. Besides specific remedies for psoriasis, moisturizers form an important part in the management of psoriasis because of the thick scaly nature of the plaques. Moisturizers enhance the penetration of topical active ingredients as well as prevents or delays side effects like skin atrophy etc. An oral antihistamine e.g. cetirizine 10 mg may be required for symptomatic relief from itching. Treatment may take 2-4 weeks to show noticeable improvement. Therefore, I would suggest him to continue with the prescribed medicines and follow up with his doctor every 2-4 weeks. Hope this helpsRegards