When you have psoriasis, topical treatments are often the first medicines you use to improve your skin’s look and feel. How they work Creams, lotions, gels, and ointments applied to the skin can help by: Reducing inflammation Slowing the turnover of skin cells Taming an overactive immune system Removing skin patches Soothing uncomfortable skin Corticosteroids Corticosteroids are some of the oldest and most effective treatments for skin conditions. For psoriasis, steroids are often the first treatment step. High-potency or ultra-high-potency steroids are used most often. One drawback to topical corticosteroids is that they can stop working as well over time. In addition, they can eventually cause thinning of the skin. Different steroid preparations and dosage strengths may be prescribed for different areas of the body. Also, your doctor may suggest switching from a steroid to another medicine, at least for a year or two. Tip: Apply a topical steroid after you towel dry from a bath or shower while the skin is still damp. The water in your skin helps the medicine penetrate more easily. Other options A manufactured form of vitamin D called calcipotriene works best for psoriasis on the body but not the face or genitals. A natural form of vitamin D called calcitriol works in a similar manner. One caution: Using too much calcitriol can lead to unhealthy calcium levels in the body. Vitamin A, or retinoids, in gel and cream form can be used alone or with a steroid. They don’t thin the skin like steroids but can still cause irritation when used daily. To reduce irritation, you may be able to use a retinoid every other day or once a week. Retinoids can raise the risk of birth defects, so they shouldn’t be used by women who are trying to get pregnant. An easy-to-spread foam medicine called clobetasol propionate can help treat psoriasis in the scalp and in hairier areas of the body. Gels and ointments with coal tar are available over the counter, but they may not work as well as other psoriasis treatments. Some people don’t like products with coal tar because they can be somewhat messy and smelly. Anthralin, available as a cream, paste, or ointment, may have a modest effect on improving skin. It’s left on the affected area for several minutes and then removed. Like coal tar, it can be messy and stain skin. Salicylic acid, often in shampoos and creams, helps reduce scaling, particularly on the scalp, palms, and soles of the feet. It works best when used with another medicine, such as a steroid, anthralin, or coal tar. Some advice for using topical treatments Can’t stand the feel of thick, greasy ointments? Ask your doctor if you can reserve the ointments for bedtime and use a lotion- or cream-based medicine for daytime. Don’t feel down if the first topical treatment you try doesn’t work. You and your dermatologist can work together to test different options and find the best one for you.