Psoriasis which is resistant to topical treatment and phototherapy is treated by medications that are taken internally by pill or injection. This is called systemic treatment. Patients undergoing systemic treatment are required to have regular blood and liver function tests because of the toxicity of the medication. Pregnancy must be avoided for the majority of these treatments. Most people experience a recurrence of psoriasis after systemic treatment is discontinued.
The three main traditional systemic treatments are methotrexate, cyclosporine and retinoids. Methotrexate and cyclosporine are immunosuppressant drugs; retinoids are synthetic forms of vitamin A.
Other additional drugs, not specifically licensed for psoriasis, have been found to be effective. These include the antimetabolite tioguanine, the cytotoxic agent hydroxyurea, sulfasalazine, the immunosuppressants mycophenolate mofetil, azathioprine and oral tacrolimus. These have all been used effectively to treat psoriasis when other treatments have failed. Although not licensed in many other countries fumaric acid esters have also been used to treat severe psoriasis in Germany for over 20 years.
Biologics are manufactured proteins that interrupt the immune process involved in psoriasis. Unlike generalised immunosuppressant therapies such as methotrexate, biologics focus on specific aspects of the immune function leading to psoriasis. These drugs (interleukin antagonists) are relatively new, and their long-term impact on immune function is unknown, but they have proven effective in treating psoriasis and psoriatic arthritis. They include Amevive, Enbrel, Humira, Remicade and Raptiva. Raptiva was withdrawn by its maker from the US market in April, 2009. Biologics are usually given by self-injection or in a doctor's office. They are very expensive and only suitable for very few patients with severe psoriasis. Ustekinumab (IL-12 and IL-23 blocker) shows hopeful results for psoriasis therapy.
In the United Kingdom in 2005 the British Association of Dermatologists (BAD) published guidelines for use of biological interventions in psoriasis
A UK national register called the BAD Biological Register (BADBIR) has been setup to collect valuable information on side effects and benefits and will be used to inform doctors on how best to use biological agents and similar drugs.
This article is licensed under the Creative Commons Attribution-ShareAlike License.
It uses material from the Wikipedia article on
All material adapted used from Wikipedia is available under the terms of the
Creative Commons Attribution-ShareAlike License.
Wikipedia® itself is a registered trademark of the Wikimedia Foundation, Inc.