There can be substantial variation between individuals in the effectiveness of specific psoriasis treatments. Because of this, dermatologists often use a trial-and-error approach to finding the most appropriate treatment for their patient.
The decision to employ a particular treatment is based on the type of psoriasis, its location, extent and severity. The patient's age, sex, quality of life, co morbidities, and attitude toward risks associated with the treatment are also taken into consideration.
Medications with the least potential for adverse reactions are preferentially employed. If the treatment goal is not achieved then therapies with greater potential toxicity may be used.The psoriasis treatment ladder
First step Medicated ointments or creams, called topical treatments, are applied to the skin. If topical treatment fails to achieve the desired goal then
Second step The next step would be to expose the skin to ultraviolet (UV) radiation. This type of treatment is called phototherapy.
Third step This step involves the use of medications which are taken internally by pill or injection. This approach is called systemic treatment.
Over time, psoriasis can become resistant to a specific therapy. Treatments may be periodically changed to prevent resistance developing (tachyphylaxis) and to reduce the chance of adverse reactions occurring.
Antibiotics are generally not indicated in routine treatment of psoriasis. However, antibiotics may be employed when an infection, such as that caused by the bacteria Streptococcus, triggers an outbreak of psoriasis, as in certain cases of guttate psoriasis.
Psychological symptom management program has been reported also as being a helpful addition to traditional therapies in the management of psoriasis.Topical treatment
Bath solutions and moisturizers help soothe affected skin and reduce the dryness which accompanies the build-up of skin on psoriatic plaques. Medicated creams and ointments applied directly to psoriatic plaques can help reduce inflammation, remove built-up scale, reduce skin turn over, and clear affected skin of plaques.
Ointment and creams containing coal tar, dithranol (anthralin), corticosteroids like desoximetasone (Topicort), vitamin D3 analogues (for example, calcipotriol), and retinoids are routinely used. Argan oil has also been used with some promising results. Activated vitamin D and its analogues are highly effective inhibitors of skin cell proliferation.
The disadvantages of topical agents are variably that they can often irritate normal skin, can be time consuming and awkward to apply, cannot be used for long periods, can stain clothing or have a strong odour. As a result, it is sometimes difficult for people to maintain the regular application of these medications. Abrupt withdrawal of some topical agents, particularly corticosteroids, can cause an aggressive recurrence of the condition. This is known as a rebound of the condition.
Some topical agents are used in conjunction with other therapies, especially phototherapy.Phototherapy
It has long been recognized that daily, short, non-burning exposure to sunlight helped to clear or improve psoriasis. Sunlight contains many different wavelengths of light. It has been recognized that for psoriasis the therapeutic property of sunlight was due to the wavelengths classified as ultraviolet (UV) light.
Ultraviolet B (UVB) (315-280 nm) is absorbed by the epidermis and has a beneficial effect on psoriasis. There are two types of UVB lamps: Narrowband UVB (311 to 312 nm), and Wideband UVB (290-320 nm). UVB Wideband is more effective and it requires shorter exposure time, while UVB Narrowband is considered safer. Exposure to UVB several times per week, over several weeks can help people attain a remission from psoriasis. Sometimes it is needed to continue the treatments once a week as maintenance, or the chronic disease will return.
In Hospitals ultraviolet light treatment is frequently combined with topical or systemic treatment as there is a synergy in their combination.Photochemotherapy (PUVA treatment)
Psoralen and ultraviolet A phototherapy (PUVA) combines the oral or topical administration of psoralen with exposure to ultraviolet A (UVA) light. The mechanism of action probably involves activation of psoralen by UVA light which inhibits the abnormally rapid production of the cells in psoriatic skin. The drug psoralen makes the skin more sensitive and responsive to this particular light. Compared with UVB treatment, PUVA treatment taken two to three times a week clears psoriasis more consistently and in fewer treatments. PUVA clears or dramatically clears psoriasis for more than 75% of patients and can lead to extended remissions.
PUVA is associated with nausea, headache, fatigue, burning, and itching Long-term treatment is associated with an increased risk of squamous cell and melanoma skin cancers. Due to the risks involved, PUVA is recommended only for moderate to severe psoriasis.
UV light aids chemical reactions that affect the function of cells. In psoriasis this means that the cells do not multiply so rapidly and behave more like normal skin. Too much UVB or UVA however is not a good thing because it burns. They can also prematurely age the skin and increase the risk of skin cancers. Wrinkling of the skin (Actinic Elastosis) and skin malignancies are associated long-term side effects. Short-term side effects are blistering with redness (erythema), which are uncomfortable but absolutely not dangerous.Systemic treatment
Psoriasis which is resistant to topical treatment and phototherapy is treated by medications that are taken internally by pill or injection. 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 has been ceased.
The three main traditional systemic treatments are methotrexate, cyclosporine and retinoids. Methotrexate and cyclosporine are immunosupressant 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 immunosupressants 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. 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.New Developments
In 2008, the FDA (US Food and Drug Administration) has approved three new treatment options available to psoriasis patients:
1) Taclonex Scalp, a new topical ointment for treating scalp psoriasis;
2) The Xtrac Velocity excimer laser system, which emits a high-intensity beam of ultraviolet light, can treat moderate to severe psoriasis;
3) The biologic drug adalimumab (brand name Humira) was also approved to treat moderate to severe psoriasis as well as psoriatic arthritis.