Treatment

Many creams, ointments, lotions, and pills are available for the treatment of psoriasis. Many patients require only over-the-counter treatment, or even none at all during relapses. About a third of patients with psoriasis, however, do not respond to over-the-counter remedies and lifestyle changes, and require aggressive treatments. In some cases, such treatments need to be lifelong.

Treatment Options

In general, the following three treatment options are used for psoriasis, from least to greatest strength:

• Topical (rub on) Medications. Options include lotions, ointments, creams, and shampoos. These may be useful for mild-to-moderate psoriasis. Topical medicines rarely produce complete clearance, however.
• Phototherapy. Options include light-wave radiation treatments using broad- or narrow- band ultraviolet B (UVB) light, or psoralen with ultraviolet A light (PUVA). This treatment is effective for moderate-to-severe psoriasis. Phototherapies are more effective than drugs and have fewer side effects than most systemic (body-wide) medications. Even more promising, in a 2000 analysis comparing several psoriasis treatments, an advanced phototherapy called narrow band UVB achieved the highest complete clearance rate (86% of patients).
• Body-Wide (Systemic) medications. This treatment employs various pills that affect the whole body, not just the skin. These medicines have significant side effects and are generally reserved for severe psoriasis.

Determining the most effective treatments requires controlled comparison studies. In any case, individual requirements vary widely, and treatment selection must be carefully discussed with the doctor.

Treatment Sequences

Giving treatment in a particular order is a strategy for providing both quick relief of symptoms and long-term maintenance. It involves three main steps:

• The quick fix, to clear the psoriatic lesions during an acute outbreak (for example, a high-strength topical steroid in mild-to-moderate psoriasis, or an oral immunosuppressant in more severe cases)
• The transitional phase, intended to gradually introduce the maintenance drug
• Ongoing maintenance therapy

Choices for transitional or maintenance treatments depend on the severity of the condition. Some examples are described in the following sections.

Rotational Therapy

In severe chronic cases, a doctor may recommend rotational therapy. This approach alternates treatments. The goal is to prevent severe side effects or build-up of resistance from long-term use of a single medicine. An example of a rotational schedule may be the following:

• The patient gets phototherapy for about 2 years.
• The patient then takes one or two powerful body-wide drugs for 1 - 2 years and stops.
• Phototherapy starts again, and the cycle repeats.

Oral and Injected Therapy

Some doctors use the Koo-Menter Psoriasis Instrument (KMPI) to decide which patients should receive a pill (oral) or an injection. The KMPI’s questions include

• Does psoriasis cover at least 5% of the patient’s body?
• Is the patient disabled by psoriasis?
• Does psoriasis affect the patient’s quality of life?

If the answer to these questions is "yes," three additional questions are considered:

• Is light therapy inappropriate for the patient?
• Is the patient’s psoriasis resistant to light therapy?
• Does the patient have psoriatic arthritis?

If the answer to these questions is “yes,” a doctor may decide to prescribe a pill or injected drugs.

Combination Therapies

Doctors increasingly use combinations of pills, creams, ointments, and phototherapy instead of single medications. Combinations of oral treatments are particularly useful, since the doses of each drug can be reduced. This lowers the risk of severe side effects. Thousands of combinations are possible, and the patient and doctor should discuss the best treatment for individual needs.