Treatments reduce inflammation and clear the skin. Treatments can be divided into three main types: topical treatments, light therapy and systemic medications.
Vitamin D analogues. These synthetic forms of vitamin D slow skin cell growth.
Anthralin. This medication helps slow skin cell growth.
Topical retinoids. These are vitamin A derivatives that may decrease inflammation. The most common side effect is skin irritation.
Calcineurin inhibitors. Calcineurin inhibitors — tacrolimus (Prograf) and pimecrolimus (Elidel) — reduce inflammation and plaque buildup.
Calcineurin inhibitors are not recommended for long-term or continuous use because of a potential increased risk of skin cancer and lymphoma. They may be especially helpful in areas of thin skin, such as around the eyes, where steroid creams or retinoids are too irritating or may cause harmful effects.
Light therapy (phototherapy)
This treatment uses natural or artificial ultraviolet light. The simplest and easiest form of phototherapy involves exposing your skin to controlled amounts of natural sunlight.
Other forms of light therapy include the use of artificial ultraviolet A (UVA) or ultraviolet B (UVB) light, either alone or in combination with medications.
Narrow band UVB phototherapy.
Psoralen plus ultraviolet A (PUVA).
Oral or injected medications
If you have severe psoriasis or it's resistant to other types of treatment, your doctor may prescribe oral or injected drugs. This is known as systemic treatment. Because of severe side effects, some of these medications are used for only brief periods and may be alternated with other forms of treatment.
Other medications. Thioguanine (Tabloid) and hydroxyurea (Droxia, Hydrea) are medications that can be used when other drugs can't be given.