Plaque Psoriasis


Plaque Psoriasis

About Plaque Psoriasis

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Psoriasis develops when the immune system turns against the body and attacks the skin and sometimes the joints. This process is called autoimmunity.  

Psoriasis causes red, thick, scaly patches on the skin called plaque psoriasis, and it is the most common type. The plaques can occur anywhere but often appear on knees, elbows, scalp, hands, feet, and lower back.

Psoriasis lesions can itch, sting, burn, or simply hurt. In some cases, they can also cause people intense anxiety. Some people may avoid social situations because they are worried about the appearance of their skin. People with psoriasis also have an increased risk of developing depression and anxiety.

Arthritis due to psoriasis can cause swelling, stiffness, and pain in the joints, which can be disabling. In some cases, this type of psoriasis can cause pits and other problems in toenails or fingernails.

Psoriasis symptoms often come and go. It's usually difficult to predict when flare-ups will occur, but having an infection or dry skin, experiencing stress, or taking certain medications can cause a flare-up.

More than 5 million adults in the U.S. suffer from psoriasis, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases. Children can also develop the ailment, but it occurs mostly in adults. It occurs about equally in men and women.

How severe your psoriasis is—how much of your body is affected by the psoriasis plaques—will be an important factor in helping you and your doctor determine which treatment might be best to try. For example, in very mild cases, there may be only a few lesions on the skin and topical creams or gels may be helpful.

But in moderate to severe psoriasis more than five to 10 percent of a person’s skin is affected. (To give you an idea of how much that is, the surface of one of your palms, including your fingers, represents about 1 percent of your entire skin surface.) Because the discomfort and itching can be so bad that it prevents a person from carrying out daily activities and reduces her quality of life, other drugs may be used, including a biologic.

There are other types of psoriasis, including guttate psoriasis—which causes small drop-like lesions on the upper back—and pustular psoriasis, which produces lesions filled with pus. But the biologic drugs have not been studied in those types of psoriasis so we do not cover them in this analysis.

Common Symptoms

  • Red, scaly patches on the skin. 
  • Discoloration of fingernails and toenails
  • If plaque psoriasis develops into psoriatic arthritis, symptoms include painful joint inflammation, stiffness and soreness


What Causes It?

Plaque psoriasis is the result of white blood cells becoming overactive and triggering a reaction of the immune system, which results in the overproduction of skin cells.


Am I at Risk?

More than 5 million adults in the U.S. suffer from psoriasis, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases. Children can also develop the ailment, but it occurs mostly in adults. It occurs about equally in men and women.

Plaque psoriasis often runs in families, and research indicates there is a genetic component to the disease.   If either of your parents have suffered from psoriasis, your risk of developing psoriasis is elevated. Other factors which may increase your risk of developing psoriasis include having a weakened immune system, smoking, and obesity. Plaque psoriasis is not contagious.

Are They Effective?

Drugs that are put on the skin or those in pill form can help relieve symptoms of psoriasis and psoriatic arthritis, but they don’t work for everyone. In those cases, injectable medications called biologics—technically known as immunomodulator therapies—may be another choice. The biologic drugs do not cure psoriasis or arthritis due to psoriasis, but they can relieve symptoms and might help prevent joint damage from getting worse.

Are They Safe?

Most of what is known about side effects of the biologics comes from trials of people with rheumatoid arthritis, Crohn’s disease, or other ailments. The risk of experiencing a side effect for people with psoriasis appears to be less because combination therapy with methotrexate and other medications that suppress the immune system were not used in psoriasis clinical trials.
The risk of experiencing side effects is an important factor to consider when choosing to take a biologic drug.

The mild side effects associated with these medicines include:

  • Headache
  • Skin reaction where the drug is injected
  • Respiratory infection
  • Urinary tract infection

Serious side effects include:

  • Allergic reactions
  • Liver damage
  • Cancer
  • Serious infections: tuberculosis, pneumonia, staph, and certain fungal infections.

Here’s what we know about specific kinds of side effects and each drug:

Skin reactions where you are given the drug
For biologics that are injected under the skin (subcutaneously)—adalimumab (Humira), certolizumab (Cimzia), etanercept (Enbrel), golimumab (Simponi), and ustekinumab (Stelara)—people commonly experience skin rashes, itching, and pain where the drug is injected.

Infusion reactions
People also sometimes experience reactions to biologic drugs injected into a vein (infusion), such as infliximab (Remicade), due to infusion reactions. These reactions can include dizziness, chills, itching, headache, and fever. In about 1 percent of people, these infusion reactions can be severe or lead to convulsions. Rarely, it has been reported that people have died after receiving a biologic injected into their vein.

About three percent to four percent of people who take a biologic drug have an infection of some kind over the course of a year. Most of these are skin or lung infections (bronchitis or pneumonia). The risk of getting an infection after receiving a biologic is about 20 percent higher than the risk with methotrexate, a drug that many people try before a biologic drug. These risks are highest during the first six months of treatment.
There are differences in the biologic drugs in the risk of certain infections they pose. For example, a British study found the risk of tuberculosis was three to four times higher for people who took adalimumab (Humira) and infliximab (Remicade) compared with etanercept (Enbrel). But the actual risk is a fairly low number—about one in every 10,000 to 20,000 people who take a biologic.
If you have signs of an infection while taking a biologic, call or see your doctor right away. These include having the chills, a cough, diarrhea, feeling tired, a fever, muscle aches, and weight loss. 

All six of the biologics evaluated have a warning on their drug label that they might increase the risk of certain cancers, including cancers of the breast and colon, lymphoma (a type of blood cancer), and certain types of skin cancers. In some cases, people have died from the cancer. 
But large, recent studies of people who took biologics for a variety of conditions have found no overall increased risk of developing cancers that can spread through the body (malignant), compared with people with who had the same diseases but who did not take biologics.

Other side effects
People have developed congestive heart failure, autoimmune ailments, such as lupus and multiple sclerosis, and serious liver reactions after starting a biologic. Most of the people improved after stopping treatment, which is an indicator that the biologic drug was the cause.
Ustekinumab (Stelara) has been associated with a single case of a brain condition called reversible posterior leukoencephalopathy syndrome, which can be fatal but is usually reversible if caught early. The person who developed the ailment completely recovered after ustekinumab was stopped.
Although infliximab (Remicade) clears severe psoriasis faster than other biologics, it has a higher rate of withdrawal due to side effects than other biologics, so it is not one of our top picks. The main reasons people stop taking it are because they have skin or allergic reactions due to intravenous administration.
Long-term risks of the older biologics have not been identified yet. The first biologic—infliximab (Remicade)—has been on the market since 1998, and many experts think that long-term risks would have been detected by now.
For the newer biologic drugs, serious problems can take five years or more to recognize, so at present, there is less certainty.  

To reduce the risk of side effects, let your doctor know if you have:

  • chronic obstructive pulmonary disease (COPD)
  • congestive heart failure
  • diabetes
  • an infection or history of infections
  • tuberculosis or a positive skin test for tuberculosis
  • viral hepatitis
  • multiple sclerosis

Also notify your doctor if you have been around a person with chickenpox, shingles, or tuberculosis, or if you are scheduled to receive a vaccine or have surgery.

The risk of biologics to unborn babies is unknown. Women of childbearing age should use contraception while on biologics. If you are planning to become pregnant, talk with your doctor about when to stop using contraception and biologics. The labeling of biologics advises these medications not be used by pregnant women unless necessary.

Drug Interactions
Biologics are often prescribed together with other medications, such as methotrexate, pain medications, or corticosteroids, and do not seem to interact with most drugs. But it’s important to note that there is little research on this issue. You should not take two or more biologics in combination. Studies show that when two or more biologics are taken at the same time, there is a substantially higher rate of serious adverse events compared to taking one of the drugs alone.

Because biologics affect your immune system, it is recommended that you should not receive "live" vaccines, such as the yellow fever vaccine or FluMist, while you are on a biologic. But in some situations, a live vaccine may be necessary (for example, rubella immunization in women of childbearing age). You should discuss the possible risks and benefits of immunizations with your doctor. Other vaccines, such as flu vaccines that don't contain the live virus, are safe and can be administered with biologic medications. Discuss with your doctor any vaccines you plan to receive and read the package insert of the biologic you are taking.

Age, Race, and Sex Differences
People older than 65 and various ethnic groups have been underrepresented in most studies of biologics. Still, the existing evidence does not indicate that any biologic is more or less effective than the others in older people, any particular race or sex, or in patients who have other diseases. 

Are There Over-the-Counter Options?

Creams, salves, lotions, sprays, and gels that you put directly on the skin, such as hydrocortisone, can all be purchased over the counter.

Are There Non-Drug Options?

Ultraviolet phototherapy or light therapy given at a doctor’s office can be used to treat plaque psoriasis. Used when large parts of the body are affected.