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Systemic Medications
Reserved for moderate
to severe psoriasis, systemic medications - medications that circulate
throughout the body - are taken orally or given by injection or
infusion. While effective, some of these medications can only be used
for limited periods of time and may be combined and rotated to minimize
side effects and toxicity. The systemic medications approved by the U.S.
Food and Drug (FDA) Administration for the treatment of psoriasis are:
Acitretin
Approved to treat severe psoriasis in adults, acitretin is a retinoid
(vitamin A derivative) that patients take orally. Studies show acitretin
is effective in treating
erythrodermic and
pustular types of psoriasis. It is effective in treating
psoriasis on the palms of the hands and soles of the feet. Combining
acitretin with phototherapy has proven effective, especially in treating
severe
plaque psoriasis, and allows for lower dosage. Since acitretin
does not suppress the immune system, it may be considered for patients
with severe psoriasis who are HIV-positive.
Dermatologists must
closely monitor their patients taking acitretin as side effects may be
experienced. Regular blood tests to check lipid (fat) levels are part of
this monitoring. Side effects include raised lipid levels in the blood;
severe headache; liver damage; hair loss; thinning of the nails; sticky
feeling to the skin; dry skin; bone spurs; and aches in the muscles,
joints or bone, especially during exercise.
Oral retinoids,
including acitretin, should not be used by women who are pregnant or
plan to become pregnant within 3 years of discontinuing therapy due to
the possibility of severe birth defects.
How it works:
Acitretin normalizes skin cells’ growth, which prevents the rapid growth
of and piling up of cells on the skin’s surface.
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Advantages
- Effective for severe psoriasis
- Possible treatment for HIV-positive patients
- May be used with phototherapy to lower the
dosage of acitretin
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Disadvantages
- Many side effects possible, some significant
- Patients must be monitored during therapy
- Cannot be prescribed to women who plan to
become pregnant within 3 years
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Biologics
For patients with moderate to severe psoriasis, the use of biologic
agents to treat psoriasis is a much-welcomed milestone. What makes
biologics unique is that these drugs pinpoint precise immune responses
involved with psoriasis. Data from studies suggests that pinpointing
specific immune responses produces less-toxic side effects because the
entire immune system is not affected and neither are organs, such as the
liver and kidneys.
Experts believe that
biologics are safe overall; however, long-term research is needed to
determine what side effects may occur with years of use. Scientists
acknowledge that altering the immune system for years on end could lead
to infections or cancer. Patients should realize that these drugs may
not work for everyone.
Three biologics —
alefacept, efalizumab, and etanercept — have been approved by the FDA
for treating adults with moderate to severe plaque psoriasis. Etanercept
also is FDA-approved for the treatment of psoriatic arthritis.
Alefacept is
given by an intramuscular injection once a week for 12 weeks. Patients
must visit their dermatologists for these weekly shots and get regular
blood tests to check their T cell (a type of white blood cell) counts.
In clinical trials, alefacept was shown to be highly effective in most
patients and to have a good safety profile. Additionally, alefacept
provides a long period of remission for many. In clinical trials, the
average remission period for those who responded was more than 7 months;
however, some remissions exceeded one year. Once remission lapses, a
repeat 12-week course of therapy can be administered if 12 weeks have
passed since the last shot was given. Side effects so far appear to be
mild and include chills and muscle aches with the first few injections.
Efalizumab is an
antibody with the ability to slip into a patient’s immune system
without being detected as “foreign.” Efalizumab, unlike other systemic
drugs used to treat psoriasis, provides continuous therapy and is meant
for long-term use. Like alefacept, efalizumab is also given by injection
once a week; however, patients can learn how to self-administer these
shots. In clinical trials, patients began to see results as early as 2
weeks after beginning treatment. Once efalizumab is stopped, signs and
symptoms usually reappear. Common side effects are headache, flu-like
symptoms, and muscle aches with the first few injections.
Etanercept, too,
is meant to provide long-term continuous therapy, and patients give
themselves injections once or twice a week. The medication has been used
by people with rheumatoid arthritis for more than 6 consecutive years,
and data indicates that etanercept has an excellent safety profile when
used for extended periods. Serious side effects remain low over time and
cumulative toxicities have not been observed. The most common side
effect is mild to moderate injection site reactions, such as redness,
itching, pain, or swelling. These reactions usually occur during the
first month and then subside.
While etanercept is
meant for continuous therapy, clinical trials show that when etanercept
is taken to treat psoriasis and stopped, psoriasis tends to gradually
return over a three-month period. In clinical trials, withdrawal was
well-tolerated and did not cause a severe psoriasis flare. Reasons to
stop taking etanercept may include the patient’s need for a vaccination,
desire to rotate with other treatment for psoriasis, or plans for a drug
“holiday.”
How they work:
Alefacept interferes with the migration as well as the activation and
proliferation of T cells (a type of white blood cell). This is what
gives patients relief from the signs and symptoms of psoriasis.
Efalizumab inhibits activation of the T cells and blocks T cell
trafficking. This prevents the T cells from entering and causing
inflammation. To gain continuous relief, efalizumab must be taken
weekly. Research shows that fairly soon after stopping efalizumab, the
signs and symptoms of psoriasis return.
Etanercept
inhibits tumor necrosis factor (TNF)-a.
It is excessive TNF-a
production that can cause the increased inflammation, swelling of
joints, scale, and thickness.
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Advantages
- Less toxic than other systemic drugs used to
treat psoriasis
- Well tolerated
- Alefacept shown to induce long remission in
some patients
- Efalizumab and etanercept provide continuous
treatment
- Etanercept can be safely withdrawn and
resumed if needed
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Disadvantages
- Expensive, cost may be prohibitive for some
- Long-term effects not known
- Not effective for all patients
- Alefacept requires weekly visits to
patient’s dermatologist
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Cyclosporine
Cyclosporine is a potent immunosuppressive drug that benefits many with
severe
plaque psoriasis and psoriasis of the nails. It is taken in pill
or liquid form. While it proves extremely effective in treating
psoriasis, it is generally reserved for patients with severe cases whose
condition has not responded to other therapies. Patients who respond
typically show rapid improvement. Due to potential side effects, kidney
function and blood pressure must be checked before the drug can be
prescribed, and these need to be monitored regularly during therapy.
Other side effects include increased risk of developing cancers,
headache, tingling or burning sensations in the arms or legs, fatigue,
abdominal upset, and musculoskeletal or joint pain.
Cyclosporine was first
used to prevent rejection in organ-transplant recipients. Its
effectiveness in treating psoriasis was discovered when an organ
recipient who had psoriasis showed significant clearing after taking
cyclosporine. This finding helped confirm that psoriasis is a
dysfunction of the immune system.
The FDA recommends that
cyclosporine not be used for more than one year. Patients must be
carefully monitored, especially with long-term use. To help patients
gain relief from the signs and symptoms of psoriasis, dermatologists may
rotate cyclosporine with other systemic drugs such as methotrexate.
How it works:
Cyclosporine inhibits T cell activity, which decreases the rapid growth
of skin cells.
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Advantages
- Highly effective in severe plaque psoriasis
and psoriasis of the nails
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Disadvantages
- Possibility of severe side effects,
including kidney damage
- Patient must be carefully monitored during
therapy
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Methotrexate
One of the first chemotherapy drugs, methotrexate has been used for
years to treat moderate to severe psoriasis and continues to be one of
the most effective therapies for patients with
erythrodermic and
pustular psoriasis. Since methotrexate has potentially serious
side effects, tests to check kidney and liver functions and blood are
run before methotrexate is prescribed. If the tests show that the
patient is a candidate for methotrexate, the patient must be carefully
monitored during therapy. Patients take methotrexate either orally or by
injection, usually once a week.
Patients who respond
typically see an improvement within 4 to 6 weeks. After the initial
clearing, the dose may be reduced or other therapies used to keep the
psoriasis under control. Common side effects include nausea, fatigue,
and headaches. Long-term side effects include liver damage, and patients
must be closely monitored.
Methotrexate is known
to cause birth defects, so pregnancy must be avoided while taking this
medication. Methotrexate must not be taken during pregnancy or while
trying to become pregnant. Due to multiple effects on the tissues, both
men and women should stop taking methotrexate for at least 12 weeks
before trying to conceive. This medication can be harmful to a nursing
infant, so breast-feeding is not recommended during treatment.
Methotrexate also is
not recommended for patients who have an active infection, liver
disease, or a history of alcohol abuse.
How it works:
Methotrexate blocks certain parts of the immune system, which decreases
skin cell proliferation (rapid growth and multiplication) and suppresses
inflammation.
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Advantages
- Highly effective in severe psoriasis,
especially erythrodermic and pustular psoriasis
- Highly effective for psoriatic arthritis
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Disadvantages
- Potentially serious side effects, including
liver damage
- Patients must be carefully monitored during
therapy
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Reference:
Gribetz, C. et al. “Clearing Psoriasis: A New Era of Optimism.”
Contemporary Dermatology 2003: Vol. 1, No. 1: 1-8.
More Information
Topical Preparations
Covers topical medications, moisturizers and agents that remove excess
scale.
Phototherapy
Explains the types of phototherapy used to treat psoriasis; includes
information about the excimer laser.
Other Systemic Medications
Research shows these drugs, which received FDA approval for treating
other conditions, may also be effective in clearing psoriasis.
AAD Consensus Statement on Psoriasis Therapy
Table lists the treatments contained in the consensus statement
developed by leading dermatologists and other experts.
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