Hello and welcome to healthcaremagic. Psoriasis is an inflammatory skin disease characterised by well defined erythematous scaly plaques with silvery white or candle wax type of scaling. Chronic plaque psoriasis is the most common type. It can affect sites like scalp, arms, and legs, (specifically elbows and knees), palms and soles etc. For the patches you could use a steroid+salicylic acid ointment, twice daily (clobetasol+3% OR 6% salicylic acid in an ointment base e.g propysalic) over and above the moisturizer for 4 weeks. Other treatment modalities which can be used for localized plaque psoriasis are: Vit D analogues like calcipotriol, calcipotriene alone or in combination with steroid. I usually prefer topical steroids for the initial 2-4 weeks and subsequently switch to topical Vit D analogues because steroids can have side effects like local skin atrophy. For scalp psoriasis, similarly i prefer to use topical steroid+salicylic acid based lotion for the initial 2-4 weeks followed by topical Vitamin D based analogues in lotion form. Coal tar+salicylic acid based shampoos are an essential part of treatment of scalp psoriasis. Many are available on prescription from a dermatologist e.g Protar lotion, Ionax-T lotion etc. regards