Vitamin D derivatives slow the rate of new skin cell production, reducing scaly and flaky skin. The most common side effects are localised and include burning, itching, and dryness.
Steroids reduce the skin inflammation associated with psoriasis. As the steroids in all of the products mentioned above are potent, they should be used short-term (1-4 weeks maximum); use them at the lowest dose for the shortest time possible to control your symptoms and reduce side effects.
Topical steroids have few side effects when used correctly. Long-term use can cause thinning of the skin, inflammation and a flare of symptoms when stopped. Your body can come to rely on these instead of producing its own natural steroids. If you are using steroid-containing psoriasis treatment on your skin, do NOT cover the affected areas with bandages, dressing or shower caps. This can increase the absorption of steroids into the body.
Salicylate softens and thins thick, scaly skin which allows the steroid treatment to penetrate more efficiently. Side effects include skin tingling/stinging, itching, and peeling. These are less common when combined with a steroid.