Doctors generally treat psoriasis in steps based on the
severity of the disease, size of the areas involved, type of psoriasis, and
the patient's response to initial treatments. This is sometimes called the
"1-2-3" approach. In step 1, medicines are applied to the skin
(topical treatment). Step 2 uses light treatments (phototherapy). Step 3
involves taking medicines by mouth or injection that treat the whole immune
system (called systemic therapy).
Over time, affected skin can become resistant to treatment,
especially when topical corticosteroids are used. Also, a treatment that works
very well in one person may have little effect in another. Thus, doctors often
use a trial-and-error approach to find a treatment that works, and they may
switch treatments periodically (for example, every 12 to 24 months) if a
treatment does not work or if adverse reactions occur.
Treatments applied directly to the skin may improve its
condition. Doctors find that some patients respond well to ointment or cream
forms of corticosteroids, vitamin D3, retinoids, coal tar, or anthralin. Bath
solutions and moisturizers may be soothing, but they are seldom strong enough
to improve the condition of the skin. Therefore, they usually are combined
with stronger remedies.
Corticosteroids--These drugs reduce
inflammation and the turnover of skin cells, and they suppress the immune
system. Available in different strengths, topical corticosteroids
(cortisone) are usually applied to the skin twice a day. Short-term
treatment is often effective in improving, but not completely eliminating,
psoriasis. Long-term use or overuse of highly potent (strong)
corticosteroids can cause thinning of the skin, internal side effects, and
resistance to the treatment's benefits. If less than 10 percent of the
skin is involved, some doctors will prescribe a high-potency
corticosteroid ointment. High-potency corticosteroids may also be
prescribed for plaques that don't improve with other treatment,
particularly those on the hands or feet. In situations where the objective
of treatment is comfort, medium-potency corticosteroids may be prescribed
for the broader skin areas of the torso or limbs. Low-potency preparations
are used on delicate skin areas.
Calcipotriene--This drug is a synthetic
form of vitamin D3 that can be applied to the skin. Applying calcipotriene
ointment (for example, Dovonex) twice a day controls the speed of
turnover of skin cells. Because calcipotriene can irritate the skin,
however, it is not recommended for use on the face or genitals. It is
sometimes combined with topical corticosteroids to reduce irritation. Use
of more than 100 grams of calcipotriene per week may raise the amount of
calcium in the body to unhealthy levels.
Retinoid--Topical retinoids are synthetic
forms of vitamin A. The retinoid tazarotene (Tazorac) is available as a
gel or cream that is applied to the skin. If used alone, this preparation
does not act as quickly as topical corticosteroids, but it does not cause
thinning of the skin or other side effects associated with steroids.
However, it can irritate the skin, particularly in skin folds and the
normal skin surrounding a patch of psoriasis. It is less irritating and
sometimes more effective when combined with a corticosteroid. Because of
the risk of birth defects, women of childbearing age must take measures to
prevent pregnancy when using tazarotene.
Coal tar--Preparations containing coal
tar (gels and ointments) may be applied directly to the skin, added (as a
liquid) to the bath, or used on the scalp as a shampoo. Coal tar products
are available in different strengths, and many are sold over the counter
(not requiring a prescription). Coal tar is less effective than
corticosteroids and many other treatments and, therefore, is sometimes
combined with ultraviolet B (UVB) phototherapy for a better result. The
most potent form of coal tar may irritate the skin, is messy, has a strong
odor, and may stain the skin or clothing. Thus, it is not popular with
Anthralin--Anthralin reduces the increase
in skin cells and inflammation. Doctors sometimes prescribe a 15- to
30-minute application of anthralin ointment, cream, or paste once each day
to treat chronic psoriasis lesions. Afterward, anthralin must be washed
off the skin to prevent irritation. This treatment often fails to
adequately improve the skin, and it stains skin, bathtub, sink, and
clothing brown or purple. In addition, the risk of skin irritation makes
anthralin unsuitable for acute or actively inflamed eruptions.
Salicylic acid--This peeling agent, which
is available in many forms such as ointments, creams, gels, and shampoos,
can be applied to reduce scaling of the skin or scalp. Often, it is more
effective when combined with topical corticosteroids, anthralin, or coal
Clobetasol propionate--This is a foam
topical medication (Olux), which has been approved for the treatment of
scalp and body psoriasis. The foam penetrates the skin very well, is easy
to use, and is not as messy as many other topical medications.
Bath solutions--People with psoriasis may
find that adding oil when bathing, then applying a moisturizer, soothes
their skin. Also, individuals can remove scales and reduce itching by
soaking for 15 minutes in water containing a coal tar solution, oiled
oatmeal, Epsom salts, or Dead Sea salts.
Moisturizers--When applied regularly over
a long period, moisturizers have a soothing effect. Preparations that are
thick and greasy usually work best because they seal water in the skin,
reducing scaling and itching.
Natural ultraviolet light from the sun and controlled delivery
of artificial ultraviolet light are used in treating psoriasis.
Sunlight--Much of sunlight is composed of
bands of different wavelengths of ultraviolet (UV) light. When absorbed
into the skin, UV light suppresses the process leading to disease, causing
activated T cells in the skin to die. This process reduces inflammation
and slows the turnover of skin cells that causes scaling. Daily, short,
nonburning exposure to sunlight clears or improves psoriasis in many
people. Therefore, exposing affected skin to sunlight is one initial
treatment for the disease.
Ultraviolet B (UVB) phototherapy--UVB is
light with a short wavelength that is absorbed in the skin's epidermis. An
artificial source can be used to treat mild and moderate psoriasis. Some
physicians will start treating patients with UVB instead of topical
agents. A UVB phototherapy, called broadband UVB, can be used for a few
small lesions, to treat widespread psoriasis, or for lesions that resist
topical treatment. This type of phototherapy is normally given in a
doctor's office by using a light panel or light box. Some patients use UVB
light boxes at home under a doctor's guidance.
A newer type of UVB, called narrowband UVB, emits the part
of the ultraviolet light spectrum band that is most helpful for psoriasis.
Narrowband UVB treatment is superior to broadband UVB, but it is less
effective than PUVA treatment (see next paragraph). It is gaining in
popularity because it does help and is more convenient than PUVA. At
first, patients may require several treatments of narrowband UVB spaced
close together to improve their skin. Once the skin has shown improvement,
a maintenance treatment once each week may be all that is necessary.
However, narrowband UVB treatment is not without risk. It can cause more
severe and longer lasting burns than broadband treatment.
Psoralen and ultraviolet A phototherapy (PUVA)--This
treatment combines oral or topical administration of a medicine called
psoralen with exposure to ultraviolet A (UVA) light. UVA has a long
wavelength that penetrates deeper into the skin than UVB. Psoralen makes
the skin more sensitive to this light. PUVA is normally used when more
than 10 percent of the skin is affected or when the disease interferes
with a person's occupation (for example, when a teacher's face or a
salesperson's hands are involved). Compared with broadband UVB treatment,
PUVA treatment taken two to three times a week clears psoriasis more
consistently and in fewer treatments. However, it is associated with more
shortterm side effects, including nausea, headache, fatigue, burning, and
itching. Care must be taken to avoid sunlight after ingesting psoralen to
avoid severe sunburns, and the eyes must be protected for one to two days
with UVA-absorbing glasses. Long-term treatment is associated with an
increased risk of squamous-cell and, possibly, melanoma skin cancers.
Simultaneous use of drugs that suppress the immune system, such as
cyclosporine, have little beneficial effect and increase the risk of
Light therapy combined with other therapies--Studies
have shown that combining ultraviolet light treatment and a retinoid, like
acitretin, adds to the effectiveness of UV light for psoriasis. For this
reason, if patients are not responding to light therapy, retinoids may be
added. UVB phototherapy, for example, may be combined with retinoids and
other treatments. One combined therapy program, referred to as the Ingram
regime, involves a coal tar bath, UVB phototherapy, and application of an
anthralin-salicylic acid paste that is left on the skin for 6 to 24 hours.
A similar regime, the Goeckerman treatment, combines coal tar ointment
with UVB phototherapy. Also, PUVA can be combined with some oral
medications (such as retinoids) to increase its effectiveness.
For more severe forms of psoriasis, doctors sometimes
prescribe medicines that are taken internally by pill or injection. This is
called systemic treatment.
methotrexate slows cell turnover by suppressing the immune system. It can
be taken by pill or injection. Patients taking methotrexate must be
closely monitored because it can cause liver damage and/or decrease the
production of oxygen-carrying red blood cells, infection-fighting white
blood cells, and clotenhancing platelets. As a precaution, doctors do not
prescribe the drug for people who have had liver disease or anemia (an
illness characterized by weakness or tiredness due to a reduction in the
number or volume of red blood cells that carry oxygen to the tissues). It
is sometimes combined with PUVA or UVB treatments. Methotrexate should not
be used by pregnant women, or by women who are planning to get pregnant,
because it may cause birth defects.
Retinoids—A retinoid, such as acitretin
(Soriatane), is a compound with vitamin A-like properties that may be
prescribed for severe cases of psoriasis that do not respond to other
therapies. Because this treatment also may cause birth defects, women must
protect themselves from pregnancy beginning 1 month before through 3 years
after treatment with acitretin. Most patients experience a recurrence of
psoriasis after these products are discontinued.
Cyclosporine—Taken orally, cyclosporine
acts by suppressing the immune system to slow the rapid turnover of skin
cells. It may provide quick relief of symptoms, but the improvement stops
when treatment is discontinued. The best candidates for this therapy are
those with severe psoriasis who have not responded to, or cannot tolerate,
other systemic therapies. Its rapid onset of action is helpful in avoiding
hospitalization of patients whose psoriasis is rapidly progressing.
Cyclosporine may impair kidney function or cause high blood pressure
(hypertension). Therefore, patients must be carefully monitored by a
doctor. Also, cyclosporine is not recommended for patients who have a weak
immune system or those who have had skin cancers as a result of PUVA
treatments in the past. It should not be given with phototherapy.
6-Thioguanine—This drug is nearly as
effective as methotrexate and cyclosporine. It has fewer side effects, but
there is a greater likelihood of anemia. This drug must also be avoided by
pregnant women and by women who are planning to become pregnant, because
it may cause birth defects.
Hydroxyurea (Hydrea)—Compared with
methotrexate and cyclosporine, hydroxyurea is somewhat less effective. It
is sometimes combined with PUVA or UVB treatments. Possible side effects
include anemia and a decrease in white blood cells and platelets. Like
methotrexate and retinoids, hydroxyurea must be avoided by pregnant women
or those who are planning to become pregnant, because it may cause birth
Biologic Response Modifiers—Recently,
attention has been given to a group of drugs called biologics, which are
made from proteins produced by living cells instead of chemicals. They
interfere with specific immune system processes which cause the
overproduction of skin cells and inflammation. Some examples are alefacept
(Amevive), etanercept (Enbrel), and efalizumab (Raptiva). These drugs are
injected (sometimes by the patient). Patients taking these treatments need
to be monitored carefully by a doctor. Since these drugs suppress the
immune system response, patients taking these drugs have an increased risk
of infection, and the drugs may also interfere with patients' taking
vaccines. Also, some of these drugs have been associated with other
diseases (like central nervous system disorders, blood diseases, cancer,
and lymphoma) although their role in the development of or contribution to
these diseases is not yet understood. Some are approved for adults only,
and their effects on pregnant or nursing women are not known.
Antibiotics—These medications are 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
There are many approaches for treating psoriasis. Combining
various topical, light, and systemic treatments often permits lower doses of
each and can result in increased effectiveness. Therefore, doctors are paying
more attention to combination therapy.
National Institute of Arthritis and
Musculoskeletal and Skin Diseases, USA.