Treatment for psoriasis usually begins with topical medicines that you spread on the affected areas of your skin. You may use one medicine or a combination of medicines to clear up the psoriasis patches. For mild psoriasis, you may be able to control psoriasis using an over-the-counter medicine.

Softening and removing psoriasis crusts and scales can help creams and other skin products be absorbed into the skin. Psoriasis crusts can be removed by gently rubbing cream into the crusts to soften them and then carefully peeling the crusted patches off. But this should be done with great care so that the skin is not irritated.

For moderate to severe psoriasis, you may need to use a topical medicine prescribed by your doctor, such as a corticosteroid or a medicine related to vitamin D called calcipotriene. Other topical medicines include anthralin and tars.

Occlusion therapy uses moisturizers or medicated creams or gels applied to the skin. After the product is applied, the skin is wrapped with tape, fabric, or plastic. Occlusion keeps the area moist and can make the medicated creams work better. Steroid cream may be used with the occlusion treatment method for small areas, but not for more than a few days.⁴ Occlusion of large areas may cause side effects such as thinning of the skin. Talk to your doctor before using occlusion therapy, to make sure that you do it safely.

Creams and ointments may be used together with sunlight or ultraviolet light, such as ultraviolet A (UVA) or B (UVB), to treat moderate psoriasis. This is called phototherapy. Treatment of psoriasis with UVB and medicines spread on the skin, such as tar or calcipotriene, is safe and effective.^{4, 7}

UVA light therapy may be combined with a medicine (called a psoralen) that makes your skin more sensitive to the UVA light. This treatment is known as PUVA (psoralen and UVA). First, you use the psoralen. You may take it as a pill, spread it on your skin as a lotion, or use it as bath salts. Then you walk into a chamber where your skin is exposed to UVA light.

Medicines taken by mouth (oral medicines) also may be used to treat moderate to severe psoriasis. The most commonly used oral medicines include methotrexate, cyclosporine, and retinoids, which are medicines related to vitamin A. In rare cases, medicine may be injected directly into a psoriasis sore or patch.

Scalp and nail psoriasis can be difficult to treat. Both conditions are more likely to improve with oral medicine. Treatment for the scalp often includes tar shampoos, corticosteroid solutions, or zinc and selenium sulfide shampoos.

If you are taking topical or oral medicines for psoriasis, you will need regular follow-up visits with your doctor to check for possible side effects. You may take one medicine for a while, then switch to another to reduce the chance that a serious side effect will occur.

Medicines called biologics have shown promise for the treatment of severe psoriasis or psoriasis that has not improved after other treatments. Biologics are similar to or the same as proteins made by the body. These medicines, including alefacept and etanercept, block the harmful response of the body's immune system that causes the symptoms of psoriasis. The long-term safety of biologics is not known.

Medication Choices

In general, treatment for psoriasis starts with medicines you spread on the affected areas of your skin (topical medicines).

Zinc pyrithione (for example, Derma-Cap) is a new nonprescription product that comes in spray, soap, or solution form. It is used to treat small patches of psoriasis and symptoms, including itching, redness, flaking, and scaling of the skin. It is also used to treat psoriasis of the scalp. For some people, it appears to eliminate scales and sores caused by psoriasis. Very few studies of zinc pyrithione have been completed.

Topical medicines that may be prescribed by your doctor to treat psoriasis include:

• Corticosteroids, which are the most common treatment for psoriasis.¹¹ Betamethasone is an example of a topical corticosteroid.
• Calcipotriene, which is a form of vitamin D.
• Retinoids, which are medicines related to vitamin A. An example is tazarotene.
• Anthralin and tars. The use of anthralin and tars has decreased recently, replaced by other medicines such as calcipotriene and tazarotene.⁴

If topical medicines alone do not relieve your psoriasis symptoms, they may be combined with exposure to ultraviolet (UV) light (phototherapy). Examples include combinations of:

• Psoralen and UVA light (called PUVA).
• Tars and UVB light (called Goeckerman treatment).
• Anthralin and UVB light (called the Ingram regimen).

If psoriasis cannot be controlled with topical medicines and ultraviolet light therapy, you may consider taking medicines by mouth (oral medicines). Oral medicines used to treat psoriasis include:

• Retinoids, which are medicines related to vitamin A. Acitretin is an example of an oral retinoid.
• Cyclosporine.
• Methotrexate.

Newer medicines, called biologics, are also approved by the U.S. Food and Drug Administration (FDA) for treatment of severe psoriasis. Biologics change the immune system response that produces the symptoms of psoriasis. These medicines are given through a needle, either into a vein or injected under the skin. Early clinical trials of biologic therapies for moderate to severe psoriasis have produced promising results. But the medicines are expensive, and long-term effects are not known. Biologics may increase the long-term risk of cancer or infections.^{12, 13, 14}

• Alefacept (Amevive), efalizumab (Raptiva), etanercept (Enbrel), and infliximab (Remicade) have been approved by the FDA for treatment of moderate to severe psoriasis.
• Etanercept, infliximab, and adalimumab (Humira) have been approved to treat psoriatic arthritis.

What To Think About

People respond differently to psoriasis treatments. A treatment that worked once may not work again. A treatment that didn't work the first time may work when tried again later.

Some medicines used to treat psoriasis can cause serious side effects. You and your doctor will discuss how long to use treatments that could cause harm. You will also need to see your doctor regularly and may have blood tests while using some medicines.

Many oral or injected medicines used to treat psoriasis are not safe during pregnancy. If you are pregnant, talk to your doctor before taking any medicines.

Researchers are studying other medicines for their safety and effectiveness in treating psoriasis. These include medicines that affect the immune system and medicines used to treat cancer.