Corticosteroids, coal tar, or creams containing salicylic acid can moisten the skin and control psoriasis flare-ups, explains WebMD. Greasy, thick creams that trap moisture in the skin tend to work best.
Corticosteroids help control skin cell growth and reduce inflammation, according to WebMD. They are available by prescription or over the counter. Coal tar also minimizes skin cell growth while improving the skin's appearance, but patients must exercise caution when using his treatment, as it can irritate the skin and stain clothing, notes Healthline. Products containing salicylic acid remove scales from the skin, and patients can use them in conjunction with other treatments.