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Psoriasis is a common skin condition where the skin develops
areas that become thick covered with silvery scales. It is a common problem, and
millions of people in the United States have psoriasis. The course of psoriasis is quite variable, but in most sufferers it is a chronic
problem that continues for years. The presence of psoriasis can cause
emotional distress.
Psoriasis is considered a skin disease, but really it is the result of
a disordered immune system. The T-cells, a type of white blood cell,
become over-stimulated. They then direct the skin to try and
"heal" a non-existent injury. The skin reacts the same way
it does when it has a fungus infection; it grows very fast, trying to
"grow" the infection off the skin. These areas become the
reddened, inflamed, patches with white scale on them.
There are several ways psoriasis can start. In most sufferers, the
tendency to get psoriasis is inherited. It is not passed on in a
simple, direct way like hair color, but involves multiple genes. For
this reason, it is not always clear from whom you inherited it.
Inherited psoriasis usually starts in older childhood or as a young
adult. Sometimes, especially in children, a virus or strep throat
triggers brief attacks of tiny spots of psoriasis.
In middle aged older adults, a non-hereditary type of psoriasis can
develop. This changes more rapidly than the inherited form, varying
in how much skin is involved more unpredictably. Most types of
psoriasis show some tendency to come and go, with variable intensity
over time.
Psoriasis flare-ups may be triggered by changes in climate,
infections, stress, excess alcohol, a drug-related rash and dry skin. Medications
may trigger a flare up weeks to months after starting them. These
include non-steroidal anti-inflammatory drugs (Indocin, Advil, Feldene,
others), blood pressure (beta-blockers such as Tenormin, Inderal),
oral steroids such as prednisone, or depression (lithium).
Psoriasis tends to be worst in those with a disordered immune system
for other reasons (cancer, AIDS or autoimmune disease). Psoriasis areas
are worsened by scratching and minor skin injuries or irritations.
Psoriasis may itch or burn. It most often occurs over the elbows,
knees, scalp, lower back, and palms or soles of the feet. The skin may
split or crack in areas that bend.
There are several forms of psoriasis. The most common form shows
reddened areas a few inches across covered by silvery scales.
Dermatologists refer to the affected areas as areas as
"plaques". Other patterns psoriasis can appear in are "inverse"
(shiny,
red patches in areas of friction such as in the folds of skin in the
groin, the armpits or under the breasts), pustular (blisters of
noninfectious pus on red skin), or "erythrodermic"
(reddening and scaling of most of the skin).
Psoriasis may also affects some of your joints, causing discomfort and
restricted motion, and even distortion. This occurs in about 10
percent of people with psoriasis. This is called "psoriatic
arthritis". It often affects only a few fingertips, but in some it can be severe and
widespread. It also may affect the fingernails, toenails and the
mucous membranes lining the genitalia and mouth.
Treatment is based on the severity of the disease and it's
responsiveness to prior treatments. The lowest level of treatment is
topical medicine are applied to the skin, the next level involves
treatments with ultraviolet light (phototherapy) and finally, taking
medicines internally. Treatments from each level are often combined,
or switched around every 12 to 24 months to reduce resistance and
adverse reactions.
A treatment that is effective in one person may fail in another. Both trial-and-error and personal preferences often guide treatment. Over
time, psoriasis tends to resist it's treatments. The locations, size
and amount of psoriasis, prior treatments, and the specific form of
the disorder are factored into treatment decisions.
Topical corticosteroids (topical "steroids") are the first
treatment most people with psoriasis get. Available in greatly varying
different strengths, short-term treatment is often effective-at least
for a while. The highest potency steroid ointments (Diprolene,
Temovate, Ultravate, or Psorcon) are almost 1000 times stronger than
over the counter 1% hydrocortisone. High-potency steroids may be used
for treatment-resistant plaques, particularly those on the hands or
feet. Overuse of high-potency steroids can lead to thinning of skin,
internal side effects treatment resistance and even worsening of the
psoriasis. Medium-potency steroids are used when larger areas or
longer treatment times are needed. For safety reasons, only
low-potency preparations are used on delicate skin areas such as the
groin or face.
Dovonex (calcipotriene) is a synthetic, activated form of vitamin D3. Regular vitamin D supplements have not benefited psoriasis, and used
in excess are dangerous. Dovonex ointment applied twice-daily controls
the excessive production of skin cells in psoriasis. The ointment mildly
irritates the skin, especially if used on the face, scalp or genitals,
where the cream or solution versions are preferred. It is slow to
work, and since it is mildly irritating, it is often combined with
topical steroids. In about a third of the people who try it, Dovonex
has almost no effect, while the rest do very well with it. To prevent
excessive accumulation of vitamin D in the body, there are limits as
to how much Dovonex can be used in a given week.
Coal tar are one of the oldest and most widely used treatments. They
are non-prescription, and are applied directly to the skin, used for a
medicated bath, or in medicated shampoos. It is available in different
strengths, the refined forms are less irritating and don't stain, but
"crude coal tar" is more potent. Because coal tar makes skin
more sensitive to ultraviolet (UV) light, it is sometimes combined
with ultraviolet B (UVB) phototherapy. Coal tar is safer than steroids
but is messy, smelly and less effective.
SCAT treatment is the short contact treatment with anthralin.
Anthralin is a very old treatment for psosiasis, but because it stains
skin and clothing brown or purple it has fallen out of favor. To limit
the staining an especially washable form (Micanol cream) is used for a
15- to 30-minute application, then carefully washed off with tepid
water. There are no dangerous side effects, and no long term skin
damage, but this treatment often fails to completely clear psoriasis
and it may irritate the skin so it is unsuitable for acute or actively
inflamed eruptions.
Salicylic acid is added to other creams to remove scales, and is in
some non-prescription creams. It is combined with topical steroids,
anthralin, or coal tar.
Tazorac is a new psoriasis gel that may be very effective. Like
Dovonex it is irritating, But it has the special benefit of clearing
psoriasis for a longer time after it is stopped than any other topical
medication. It is often combined with topical steroids to limit the
irritation. It is not clear it is safe for pregnant women, and may
cause sun sensitivity where it is applied.
Psoriasis sufferers may find that a medicated bath may help soothe the
skin, remove scales and reduce itching. These are done by soaking 15
minutes in oatmeal (Aveeno colloidal oilated Oatmeal, Epsom salts, or
Dead Sea salts or Tar (Zetar emulsion, Balnetar oil). Application of a
greasy ointment after the bath Elta, Vaseline) is particularly
helpful.
Ultraviolet light inhibits the immune system cells in the skin, and stimulates production of acivated vitamin D. These slow the excessive
of skin growth that causes scaling. Ultraviolet light treatments include
the milder UVB for the more severe or extensive psoriasis (psoralen
and ultraviolet A [PUVA] therapy. Sunlight and tanning booths tend to be
less effective, but can be used if appropriate plan is followed.
UVB Phototherapy - Artificial sources of UVB light work similar to
sunlight. For extensive psoriasis it is more practical to start with
UVB treatments instead of topical agents. UVB phototherapy also is
used to treat psoriasis that does not clear with topical treatment.
This is given in the office in a light booth three to five times
weekly for twenty to thirty treatments. For some patients who need
long term maintenance, home UVB light boxes can be prescribed. UVB is
less effective if used with topical steroid medications.
Prior to UVB treatment, something is applied to the skin. This
includes oil (baby oil, mineral oil, Robathol), coal tar ("Goeckerman"),
or a coal tar bath, UVB phototherapy, and then application of an
anthralin-salicylic acid paste ("Ingram ") left on the skin
for 6 to 24 hours. The Ingram regimen is usually given only in a
psoriasis day care center. The nearest such center is Dr. Bagel's
office in East Widnsor, NJ.
PUVA - This treatment involves taking oral Oxsoralen-Ultra capsules, then
exposure to ultraviolet A (UVA) light. UVA light is normally not
effective for psoriasis, but the Oxsoralen makes the body more
sensitive to UVA light. PUVA is normally used when more than 10
percent of the body's skin is affected or when rapid clearing is
required because the psoriasis has such a negative effect on their
life. PUVA treatment is more potent than UVB. PUVA tends to cause skin
cancer if given too long or mixed with the drugs methotrexate or
Neoral. Both PUVA and UVB are be made even more effective when given
with low doses of the drug Soriatane is combined with it (called re-PUVA).
Doctors sometimes prescribe medicines that are taken internally for
more severe forms of psoriasis, particularly when more than 10 percent of
the body is involved.
Retinoids - These drugs are derived from vitamin A and include
Soriatane and Accutane. Soriatane is most effective against pustular
and erythrodermic psoriasis, but is also good for plaque psoriasis
when combined with UVB. Both drugs can cause birth defects in pregnant
women. Accutane is against pustular psoriasis, less effective, but out
of your system faster.
Methotrexate - This treatment, which can be taken by pill, liquid or
injection suppresses the immune system just enough to control the
psoriasis. Patients taking methotrexate must be closely monitored
because this drug can cause liver damage or damage the blood producing
bone marrow. Alcoholics and patients with long-term medical problems
can not take this drug.
Hydroxyurea (Hydrea) - Compared with methotrexate, hydroxyurea is less
toxic but also less effective. Hydroxyurea is sometimes combined with
PUVA or retinoids. Some degree of anemia and decrease in white blood
cells and platelets is usual. Like methotrexate, pregnant women or
those who are planning to get pregnant must avoid hydroxyurea.
Antibiotics - Although seldom used in routine treatment, High doses of
antibiotics are being used in some centers (such as Dr. Rosenberg's
clinic Tennessee) as an experimental
treatment for psoriasis. It has become standard to give antibiotics
when an infection such as strep throat has triggered the outbreak of
psoriasis, but it's effectiveness is far from convincing.
The newest approved treatments are Neoral (cyclosporin-A), which works
directly on the T cells. It is only safe to use for a time-no more
than 6 to 12 months at a time. Also evolving is the use of Cellcept (mycophenolate
Mofetil), which seems to have less side effects. Psoriasis is an active area of medical research, and new developments
are continually being put forth.
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