Psoriasis Symptoms, Causes, Treatment Information and Medication on MedicineNet.com

What is psoriasis?

Psoriasis is a noncontagious common skin condition that causes rapid skin cell reproduction resulting in red, dry patches of thickened skin. The dry flakes and skin scales are thought to result from the rapid buildup of skin cells. Psoriasis commonly affects the skin of the elbows, knees, and scalp.

Some people have such mild psoriasis (small, faint dry skin patches) that they may not even suspect that they have a medical skin condition. Others have very severe psoriasis where virtually their entire body is fully covered with thick red, scaly skin.

Psoriasis is considered a non-curable, long-term (chronic) skin condition. It has a variable course, periodically improving and worsening. Sometimes psoriasis may clear for years and stay in remission. Some people have worsening of their symptoms in the colder winter months. Many people report improvement in warmer months, climates, or with increased sunlight exposure.

Psoriasis is seen worldwide, in all races, and both sexes. Although psoriasis can be seen in people of any age, from babies to seniors, most commonly patients are first diagnosed in their early adult years.

Patients with more severe psoriasis may have social embarrassment, job stress, emotional distress, and other personal issues because of the appearance of their skin.

What causes psoriasis?

The exact cause remains unknown. There may be a combination of factors, including genetic predisposition and environmental factors. It is common for psoriasis to be found in members of the same family. The immune system is thought to play a major role. Despite research over the past 30 years looking at many triggers, the "master switch" that turns on psoriasis is still a mystery.

What does psoriasis look like? What are the symptoms?

Psoriasis typically looks like red or pink areas of thickened, raised, and dry skin. It classically affects areas over the elbows, knees, and scalp. Essentially any body area may be involved. It tends to be more common in areas of trauma, repeat rubbing, use, or abrasions.

Psoriasis has many different appearances. It may be small flattened bumps, large thick plaques of raised skin, red patches, and pink mildly dry skin to big flakes of dry skin that flake off.

There are several different types of psoriasis including psoriasis vulgaris (common type), guttate psoriasis (small, drop like spots), inverse psoriasis (in the folds like of the underarms, navel, and buttocks), and pustular psoriasis (liquid-filled yellowish small blisters). Additionally, a separate entity affecting primarily the palms and the soles is known as palmoplantar psoriasis.

Sometimes pulling of one of these small dry white flakes of skin causes a tiny blood spot on the skin. This is medically referred to as a special diagnostic sign in psoriasis called the Auspitz sign.

Genital lesions, especially on the head of the penis, are common. Psoriasis in moist areas like the navel or area between the buttocks (intergluteal folds) may look like flat red patches. These atypical appearances may be confused with other skin conditions like fungal infections, yeast infections, skin irritation, or bacterial Staph infections.

On the nails, it can look like very small pits (pinpoint depressions or white spots on the nail) or as larger yellowish-brown separations of the nail bed called "oil spots." Nail psoriasis may be confused with and incorrectly diagnosed as a fungal nail infection.

On the scalp, it may look like severe dandruff with dry flakes and red areas of skin. It may be difficult to tell the difference between scalp psoriasis and seborrhea (dandruff). However, the treatment is often very similar for both conditions.

Can psoriasis affect my joints?

Yes, psoriasis is associated with joint problems in about 10%-35% of patients. In fact, sometimes joint pains maybe the only sign of the disorder with completely clear skin. The joint disease associated with psoriasis is referred to as psoriatic arthritis. Patients may have inflammation of any joints (arthritis), although the joints of the hands, knees, and ankles tend to be most commonly affected. Psoriatic arthritis is an inflammatory, destructive form of arthritis and is treated with medications to stop the disease progression.

The average age for onset of psoriatic arthritis is 30-40 years of age. In most cases, the skin symptoms occur before the onset of the arthritis.

The diagnosis of psoriatic arthritis is typically made by a physician examination, medical history, and relevant family history. Sometimes, lab tests and X-rays may be used to determine the severity of the disease and to exclude other diagnoses like rheumatoid arthritis and osteoarthritis.

Can psoriasis affect only my nails?

Yes, psoriasis may involve solely the nails in a limited number of patients. Usually, the nail symptoms accompany the skin and arthritis symptoms. Nails may have small pinpoint pits or large yellowish separations of the nail plate called "oil spots." Nail psoriasis is typically very difficult to treat. Treatment option are somewhat limited and include potent topical steroids applied at the nail-base cuticle, injection of steroids at the nail-base cuticle, and oral or systemic medications as described below for the treatment of psoriasis.

How many people have psoriasis?

Psoriasis is a fairly common skin condition and is estimated to affect approximately 1%-3% of the U.S. population. It currently affects roughly 7.5 to 8.5 million people in the U.S. It is seen worldwide in about 125 million people. Interestingly, African Americans have about half the rate of psoriasis as Caucasians.

Is psoriasis curable?

No, psoriasis is not currently curable. However, it can go into remission and show no signs of disease. Ongoing research is actively making progress on finding better treatments and a possible cure in the future.

Is psoriasis contagious?

No. Research studies have not shown it to be contagious from person to person. You cannot catch it from anyone, and you cannot pass it to anyone else by skin-to-skin contact. You can directly touch someone with psoriasis every day and never catch the skin condition.

Can I pass psoriasis on to my children?

Yes, it is possible. Although psoriasis is not contagious from person to person, there is a known genetic tendency, and it may be inherited from parents to their children. It does tend to run in some families, and a family history is helpful in making the diagnosis.

What kind of doctor treats psoriasis?

Dermatologists specialize in the diagnosis and treatment of psoriasis, and rheumatologists specialize in the treatment of joint disorders and psoriatic arthritis. Many kinds of physicians may treat psoriasis, including dermatologists, family physicians, internal medicine physicians, rheumatologists, and other medical doctors. Some patients have also seen other allied health professionals such as acupuncturists, holistic practitioners, chiropractors, and nutritionists.

The American Academy of Dermatology have excellent references to help find physicians who specialize in this disease. Not all dermatologists and rheumatologists treat psoriasis. The National Psoriasis Foundation has one of the most up-to-date databases of current psoriasis specialists.

How is psoriasis treated?

There are many effective treatment choices for psoriasis. The best treatment is individually determined by the treating physician and depends, in part, on the type of disease, the severity, and the total body area involved.

For mild disease that involves only small areas of the body (like less than 10% of the total skin surface), topical (skin applied) creams, lotions, and sprays may be very effective and safe to use. Occasionally, a small local injection of steroids directly into a tough or resistant isolated psoriasis plaque may be helpful.

For moderate to severe disease that involves much larger areas of the body (like 20% or more of the total skin surface), topical products may not be effective or practical to apply. These cases may require systemic or total body treatments such as pills, light treatments, or injections. Stronger medications usually have greater associated possible risks.

For psoriatic arthritis, systemic medications that can stop the progression of the disease may be required. Topical therapies are not effective.

It is important to keep in mind that as with any medical condition, all medications carry possible side effects. No medication is 100% effective for everyone, and no medication is 100% safe. The decision to use any medication requires thorough consideration and discussion with your physician. The risks and potential benefit of medications have to be considered for each type of psoriasis and the individual patient. Some patients are not bothered at all by their skin symptoms and may not want any treatment. Other patients are bothered by even small patches of psoriasis and want to keep their skin clear. Everyone is different and, therefore, treatment choices also vary depending on the patient's goals and expressed wishes.

A particularly effective approach to psoriasis has been commonly called "rotational" therapy. This is a common practice among some dermatologists who recommend changing cycles of psoriasis treatments every six to 24 months in order to minimize the possible side effects from any one type of therapy or medication.

For example, if a patient has been using oral methotrexate for two years, then it may be reasonable to take them off of methotrexate and try light therapy or a biologic injectable medication for a while. By rotating to a medication that doesn't affect the liver, the potential of cumulative liver damage may be reduced.

In another example, a patient who has been using strong topical steroids over large areas of their body for prolonged periods may benefit from stopping the steroids for a while and rotating onto a different therapy like calcipotriene (Dovonex), light therapy, or an injectable biologic.

What creams or lotions are available?

Topical (skin applied) medications include topical corticosteroids, vitamin D analogue creams (Dovonex), topical retinoids (Tazorac), moisturizers, topical immunomodulators (tacrolimus and pimecrolimus), coal tar, anthralin, and others.

Topical corticosteroids (steroids, such as hydrocortisone) are very useful and often the first-line treatment for limited or small areas of psoriasis. These come in many preparations, including sprays, liquid, creams, gels, ointments, and mousses. Steroids come in many different strengths, including stronger ones are used for elbows, knees, and tougher skin areas and milder ones for areas like the face, underarms, and groin. These are usually applied once or twice a day to affected skin areas.

Strong steroid preparations should be limited in use. Overuse or prolonged use may cause problems including potential permanent skin thinning and damage called atrophy.

A vitamin D analogue cream called calcipotriene (Dovonex) has also been useful in psoriasis. The advantage of calcipotriene is that it is not known to overly thin the skin like topical steroids. It is important to note that this drug is not regular vitamin D and is not the same as taking regular vitamin D or rubbing it on the skin.

Calcipotriene may be used in combination with topical steroids for better results. There is a newer two-in-one combination preparation of calcipotriene and a topical steroid called Taclonex. Results with calcipotriene alone may be slower and less than results achieved with typical topical steroids. Not all patients may respond to calcipotriene as well as to topical steroids.

A special precaution with calcipotriene is that it should not be used on more than 20% of the skin in one person. Overuse may cause absorption of the drug and an abnormal rise in body calcium levels.

Moisturizers, especially with therapeutic concentrations of salicylic acid, lactic acid, urea, and glycolic acid may be helpful in psoriasis. These moisturizers are available as prescription and nonprescription forms. These help moisten and lessen the appearance of thickened psoriasis scales. Some available preparations include Salex (salicylic acid), AmLactin (lactic acid), or Lac-Hydrin (lactic acid) lotions. These may be used one to three times a day on the body and do not generally have a risk of problematic skin thinning (atrophy). Overuse or use on broken, inflamed skin may cause stinging, burning, and more irritation. These stronger preparations should not be used over delicate skin like eyelids, face, or genitals. Other bland moisturizers including Vaseline and Crisco vegetable shortening may also be helpful in at least reducing the dry appearance of psoriasis.

Immunomodulators (tacrolimus and pimecrolimus) have also been used with some success in limited types of psoriasis. These have the advantage of not causing skin thinning. They may have other potential side effects, including skin infections and possible malignancies (cancers). The exact association of these immunomodulator creams and cancer is controversial.

Bath salts or bathing in high-salt-concentration waters like the Dead Sea in the Middle East may help some psoriasis patients. Epsom salt soaks (available over the counter) may also be helpful for a number of patients. Overall, these are quite safe with very few possible side effects.

Coal tar is available in multiple preparations, including shampoos, bath solutions, and creams. Coal tar may help reduce the appearance and decrease the flakes in psoriasis. The odor, staining, and overall messiness with coal tar may make it harder to use and less desirable than other therapies. A major advantage with tar is lack of skin thinning.

Anthralin is available for topical use as a cream, ointment, or paste. The stinging, possible irritation, and skin discoloration may make this less acceptable to use. Anthralin may be applied for 10-30 minutes to psoriatic skin.

What oral medications are available?

Oral medications include acitretin, cyclosporine, methotrexate, mycophenolate mofetil, and others. Oral prednisone (corticosteroid) is generally not used in psoriasis and may cause a disease flare if administered to many patients.

Acitretin (Soriatane) is an oral drug used for certain types of psoriasis. It is not effective in all types of the disease. It may be used in males and females who are not pregnant and not planning to become pregnant for at least three years. The major side effects include dryness of skin and eyes and temporarily elevated levels of triglycerides and cholesterol (fatty substance) in the blood. Blood tests are generally required before starting this therapy and periodically to monitor triglyceride levels. Patients should not become pregnant while on this drug and usually for at least three years after stopping this medication.

Cyclosporine is a potent immunosuppressive drug used for other medical uses, including organ-transplant patients. It may be used for severe, difficult-to-treat cases of widespread psoriasis. Improvement and results may be very rapid in onset. It may be hard to get someone off of cyclosporine without flaring their psoriasis. Because of the potential cumulative toxicity, cyclosporine should not be used for more than one to two years for most psoriasis patients. Major possible side effects include kidney and blood-pressure problems.

Methotrexate is a common drug used for rheumatoid arthritis and, in high doses, for cancer treatment. For psoriasis, it has been used effectively for many years. It is usually given in small weekly doses (5 mg-15 mg). Blood tests are required before and during therapy. The drug may cause liver damage in some patients, particularly if there is preexisting liver disease or if given for prolonged periods of time. Close physician monitoring and monthly to quarterly visits and labs are generally required.

What injections or infusions are available?

The newest category of psoriasis drugs are called biologics. All biologics modulate (adjust) and sometime suppress (quiet) the immune system that is overactive in psoriasis. Currently available biologic drugs include alefacept (Amevive), adalimubab (Humira), infliximab (Remicade), etanercept (Enbrel), and ustekinumab. Newer drugs are in development and may be on the market in the near future. As this class of drugs is fairly new, ongoing monitoring and adverse effect reporting continues and long-term safety continues to be monitored. Although previously available, efalizumab (Raptiva) was removed from the U.S. market in early 2009 due to reported safety concerns for the development of a serious brain infection, progressive multifocal leukoencephalopathy (PML). Individuals still taking Raptiva should contact their health-care professional to discuss risks and benefits of treatment with this drug.

Some biologics are self-injections for home use, while others are intramuscular injections or intravenous infusions in the physician's office.

Biologics have some screening requirements such as a tuberculosis screening test (TB skin test or PPD test) and other labs prior to starting therapy.

As with any drug, side effects are possible with all biologic drugs. Common potential side effects include mild local injection-site reactions (redness and tenderness). There is concern of serious infections and potential malignancy with nearly all biologic drugs.

Precautions include patients with known or suspected hepatitis B or C infection, active tuberculosis, and possibly HIV/AIDS. As a general consideration, these drugs may not be an ideal choice for patients with a history of cancer and patients actively undergoing cancer therapy.

In particular, there may be an increased association of lymphoma in patients taking biologics. It is not at all certain if this association is directly caused by these drugs. In part, this is because it is known that certain diseases like rheumatoid arthritis or psoriasis may be associated with an inherent increase in the overall risk of some infections and malignancies.

Biologics are expensive medications ranging in price from several to tens of thousands of dollars per year per person. Their use may be limited by availability, cost, and insurance approval. Not all insurance drug plans may fully cover these drugs for all conditions. Patients need to check with their insurance and may require a prior authorization request for coverage approval. Some of the biologics manufacturers have patient-assistance programs to help with financial issues.

The choice of the right medication for your condition depends on many medical factors. Additionally, convenience of receiving the medication and lifestyle may be factors in choosing the right biologic medication.

Currently, the four main classes of biologic drugs for psoriasis are:

tumor necrosis factor

TNF blockers

TNF blockers include Enbrel (etanercept), Remicade (infliximab) and Humira (adalimumab). TNF-alpha blocking drugs may have an advantage of treating psoriatic arthritis and psoriasis skin disease. Their disadvantage is that some patients may notice a decrease in the effectiveness of TNF-alpha blocking drugs over months to years.

TNF blockers are generally not used in patients with demyelinating (neurological) diseases like multiple sclerosis, congestive heart failure, or patients with severe overall low blood counts called pancytopenia.

The major side effect of these class of drugs is suppression of the immune system. Because of the increased risk of infections while on these drugs, patients should promptly report fevers or signs of infection to their physicians. Minor side effects have included autoimmune conditions like lupus or flares in lupus. Additionally, it is best to avoid any live vaccines while using TNF blockers.

Enbrel (etanercept) is a self-injectable medication for home use. It is injected via a small needle just under the skin, called subcutaneous injection. It is usually dosed once or twice week by patients at home after training with their physician or the nursing staff. Sometimes a higher loading dose is used for the first 12 weeks and then it is "stepped down" to half the dose after the first 12 weeks. Enbrel has the advantage of at least 16 years of clinical use and long-term experience.

Remicade (infliximab) is an intravenous (IV) medication strictly for physician office or special infusion medical center use. It is dosed specifically based on your weight. It is currently not for home use or self-injection. It is injected slowly over time via a small needle into a vein. It may usually be dosed once a week. There have been reports of antibodies to this drug in patients taking it for some time. These antibodies may cause a greater drug-dose requirement for achieving disease improvement or failure to improve. The IV route may be more time-consuming, requiring physician during the infusions. Remicade has the advantage of fast disease response and good potency.

Humira (adalimumab) is a self-injectable medication for home use. It is injected via a small needle just under the skin as a subcutaneous dose. It is usually dosed once every other week, totaling 26 injections in one year. Dosing is individualized and should be discussed with your physician. Sometimes a higher loading dose is used for the first dose (80 mg) and then it is continued at 40 mg every other week. It may give results as soon as one to two weeks of therapy. Humira has the advantage of at least 11 years of clinical use and long-term experience.

Drugs that block T-cell activation and the movement of T-cells

Raptiva (efalizumab) blocks both T-cell activation and the movement of T-cells into the skin. As noted above, Raptiva was withdrawn by the manufacturer from the U.S. market in April 2009 following a black-box warning issued in late 2008 by the U.S. Food and Drug Administration. (FDA). Raptiva may continue to be available in other countries.

It is dosed specifically based on your weight. Labs are required before starting injections and weekly for the 12 weeks of therapy. Injections are placed just under the skin (subcutaneous) and may be given in the physician's office or at home.

Raptiva seems to work well over several years without losing its effectiveness, therefore having the advantage of "staying power." Raptiva may cause flares of arthritis in some patients. Raptiva may also cause a decrease or drop in the platelet (blood-clotting element) count. Platelet counts are usually checked before starting and periodically (often quarterly) while patients continue Raptiva.

As with other biologics, live vaccines are not advised while patients are taking Raptiva. It is usually best to have any required vaccines weeks before starting therapy.

As with all biologics, Raptiva has been associated with possible infections and malignancy (cancer). The relative risk of these two side effects is fairly low. The most serious reported side effect in patient taking Raptiva was the onset of progressive multifocal leukoencephalopathy (PML) in several patients. PML is a rare, potentially fatal, severe neurologic disorder which is thought to be caused by a particular viral infection of brain. PML usually occurs in individuals whose immune system is weakened or suppressed and leads to permanent loss of brain function. Symptoms of PML include unusual weakness, visual changes, loss of coordination, difficulty speaking, and personality changes.

Drugs that decrease the number of activated T-cells

Amevive (alefacept) decreases the number of available activated T-cells that play a role in causing psoriasis. It is given intramuscularly (injected in the muscle) usually in the physician's office and given once a week for 12 weeks. Many patients may see improvement in their symptoms that lasts approximately 12 months (more or less). Amevive may not be uniformly effective for all patients, and some patients improve more than others. The average time to maximum improvement for many patients is about 14 weeks.

Amevive should generally not be used in patients with HIV infections as the drug causes a decrease in the CD4 cells (part of the immune system that HIV also attacks).

Also, because of the immune-system suppression, Amevive may not be a good choice in patients with active cancer or infection. As Amevive is one of the two currently available drugs that inhibits T cells directly, there may be a potential concern for immunosuppression and increased susceptibility to infections including PML. The risks and benefits of treatment with biologics need to be assessed for each individual.

Drugs that interfere with interleukin mechanisms

Ustekinumab is the newest biologic injectable medication used to modulate the immune system. It is an interleukin-12/23 human monoclonal antibody. Ustekinumab targets chemical messengers in the immune system involved in skin inflammation and skin-cell production. This drug is planned to be dosed subcutaneously (just under the skin) once a quarter (every three months). It has been very promising with very good clearance rates in the clinical trials thus far. A major advantage may be the convenience of a quarterly medication. The concerns for infection and malignancy may be similar to the other biologics.

What about light therapy?

Light therapy is also called phototherapy. There are several types of traditional medical light therapies called PUVA, UVB, and narrow band UVB. These artificial light sources have been used for decades and generally available in a physician's office. There are a few companies who may sell light boxes or light bulbs for prescribed home light therapy.

Natural sunlight is also used to treat psoriasis. Daily, short, controlled exposures to natural sunlight may help or clear psoriasis in some patients. Skin unaffected by psoriasis and sensitive areas such as the face and hands may need to be protected during sun exposure.

There are also multiple newer light sources like lasers and photodynamic therapy (use of a light activating medication and a special light source) that have been used to treat psoriasis.

PUVA is a special treatment using a photosensitizing drug and timed artificial-light exposure. The photosensitizing drug in PUVA is called psoralen. These treatments are usually administered in a physician's office two to three times per week. Several weeks of PUVA is usually required before seeing significant results. The light exposure time is slowly and gradually increased during each subsequent treatment.

Psoralens may be given orally as a pill or topically as a bath or lotion. After a short incubation period, the skin is exposed to a special wavelength of ultraviolet light called UVA. Patients using PUVA are generally sun sensitive and must avoid sun exposure for a period of time after PUVA.

Common side effects with PUVA include burning, tanning of the skin, potential skin damage, increased brown spots called lentigines, and possible increased risk of skin cancer, including melanoma. The relative increase in skin cancer risk with PUVA treatment is controversial. PUVA treatments need to be closely monitored by a physician and discontinued when a maximum number of treatments have been reached.

UVB phototherapy is an artificial light treatment using a special wavelength of light. It is frequently given daily or two to three times per week. UVB is also a component of natural sunlight. UVB dosage is based on time and exposure is gradually increased by 15-60 seconds per treatment or per week. Potential side effects with UVB include skin burning, skin damage, and possible increased risk of skin cancer, including melanoma. The relative increase in skin cancer risk with UVB treatment needs further study.

Sometimes UVB is combined with other treatments such as tar application. Goeckerman is the name of a special psoriasis therapy using this combination. Some centers have used this therapy in a "day care" type of setting where patients are in the psoriasis treatment clinic all day for several weeks and go home each night.

Where can I get more information on psoriasis?

Your dermatologist, the American Academy of Dermatology at http://www.AAD.org

There are many ongoing clinical trials for psoriasis all over the United States and in the world. Many of these clinical trials are ongoing at academic or university medical centers and are frequently open to patients without cost.

Clinical trials frequently have specific requirements for types and severity of psoriasis that may be enrolled into a specific trial. Patients need to contact these centers and inquire regarding the specific study requirements. Some studies have restrictions on what recent medications have been used for psoriasis, current medication, and overall health.

Some of the many medical centers in the U.S. offering clinical trials for psoriasis include the University of California, San Francisco Department of Dermatology, the University of California, Irvine Department of Dermatology, and the St. Louis University Medical School.

What is my long-term prognosis with psoriasis?

Overall, the prognosis for most patients with psoriasis is good. While it is not curable, it is controllable. There have been a few studies showing a possible association of psoriasis and other medical conditions, including obesity and heart disease.

What does the future hold?

Psoriasis research is heavily funded and holds great promise for the future. Just the last five to 10 years have brought great strides forward in treatment of the disease with medications aimed at treating the overactive immune system that causes the skin inflammation of psoriasis. Ongoing research is needed to decipher the ultimate underlying cause of this disease.

Psoriasis At A Glance

Psoriasis is a chronic inflammatory skin disease.
Psoriasis has no known cause.
The tendency toward developing psoriasis is inherited in genes.
Psoriasis is not contagious.
Psoriasis gets better and worse spontaneously and can have periodic remissions (clear skin).
Psoriasis is controllable with medication.
Psoriasis is currently not curable.
There are many promising therapies including newer biologic drugs.
Future research for psoriasis is promising.