Psoriasis

Psoriasis Overview

What Is Psoriasis?

Unpredictable and irritating, psoriasis is one of the most baffling and persistent of skindisorders. It’s characterized by skin cells that multiply up to 10 times faster than normal. As underlying cells reach the skin’s surface and die, their sheer volume causes raised, red plaques covered with white scales. Psoriasis typically occurs on the knees, elbows, and scalp, and it can also affect the torso, palms, and soles of the feet.

The symptoms of psoriasis vary depending on the type you have. Some common symptoms for plaque psoriasis — the most common variety of the condition — include:

• Plaques of red skin, often covered with loose, silver-colored scales; these lesions may be itchy and painful, and they sometimes crack and bleed. In severe cases, the plaques of irritated skin will grow and merge into one another, covering large areas.
• Disorders of the fingernails and toenails, including discoloration and pitting of the nails; the nails may also begin to crumble or detach from the nail bed.
• Plaques of scales or crust on the scalp
• Psoriasis can also be associated with psoriatic arthritis, which leads to pain and swelling in the joints. The National Psoriasis Foundation estimates that between 10% to 30% of people with psoriasis also have psoriatic arthritis.

Other forms of psoriasis include:

Pustular psoriasis​:​ characterized by red and scaly skin on the palms of the hands and/or feet with tiny pustules
Guttate psoriasis​:​ which often starts in childhood or young adulthood, is characterized by small, red spots, mainly on the torso and limbs. Triggers may be respiratory infections, strep throat, tonsillitis, stress, injury to the skin, and use of anti-malarial and beta-blocker medications.
Inverse psoriasis​:​ characterized by bright red, shiny lesions that appear in skin folds, such as the armpits, groin area, and under the breasts
Erythrodermic psoriasis​:​ characterized by periodic, fiery redness of the skin and shedding of scales in sheets; this form of psoriasis, triggered by withdrawal from a systemic psoriasis treatment, severe sunburn, infection, and certain medications, requires immediate medical treatment, because it can lead to severe illness.

People who suffer from psoriasis know that this uncomfortable and at times disfiguring skin disease can be difficult and frustrating to treat. The condition comes and goes in cycles of remissions and flare-ups over a lifetime. While there are medications and other therapies that can help to clear up the patches of red, scaly, thickened skin that are the hallmark of psoriasis, there is no cure.

What Causes Psoriasis?

A variety of factors — ranging from emotional stress and trauma to streptococcal infection — can cause an episode of psoriasis. Recent research indicates that some abnormality in the immune system is the key cause of psoriasis. As many as 80% of people having flare-ups report a recent emotional trauma, such as a new job or the death of a loved one. Most doctors believe such external stressors serve as triggers for an inherited defect in immune function.

Injured skin and certain drugs can aggravate psoriasis, including certain types of blood pressure medications (like beta-blockers), the anti-malarial medication hydroxychloroquine, and ibuprofen (Advil, Motrin, etc.).

Psoriasis tends to run in families, but it may be skip generations; a grandfather and his grandson may be affected, but the child’s mother never develops the disease. Although psoriasis may be stressful and embarrassing, most outbreaks are relatively harmless. With appropriate treatment, symptoms generally subside within a few months.

Is Psoriasis Contagious?

Psoriasis causes red, scaly patches to appear on the skin. It can look like a rash, so you may worry that you could get it from someone else or pass it to others. But rest easy: It’s not contagious. You cannot catch the disease by touching someone who has it.

What Causes Psoriasis?

Though psoriasis symptoms show up on the skin, the condition is actually a problem with the immune system, called an autoimmune disease. It means the body’s defenses overreact or react at the wrong times, which affects the body inside and out.

When people have psoriasis, their immune systems cause skin cells to grow much faster than normal. They pile up too quickly and form thick, scaly lesions.

There are several different kinds of the disease, but the most common is plaque psoriasis. Lesions often appear on the knees, elbows, or scalp, although they can be anywhere on the body. These patches can feel swollen, itchy, and sore, and may crack and bleed. Other types of the condition may cause small red spots, pus-filled bumps, or red scaling patches all over.

How Do People Get Psoriasis?

Scientists know that certain genes are linked to psoriasis. So if someone in your family has the condition, you may have the same genes and be more likely to get it yourself.

Even when people have the right mix of genes, however, they also need something that triggers, or wakes up, their disease. It could be something physical, like a cut, scratch, bad sunburn, or an infection like strep throat. Stress, some medications, and cold weather (which can cause dry, cracked skin) are also common triggers. But being around someone else with psoriasis is not.

Once something triggers psoriasis, it becomes a long-lasting condition. That means most people have it for the rest of their lives, although they may be able to control it with medication and other treatment.

What About Physical Contact?

Before doctors knew what caused psoriasis, they often confused it with leprosy — and people who had it were considered contagious. But now we know that you cannot catch the condition by brushing up against someone who has it. You also can’t get it from kissing, having sex, or swimming in the same water.

People get psoriasis because of their genes, not because of bad hygiene, their diet or lifestyle, or any other habits. They didn’t get it from someone else, and they cannot infect others.

Even so, there’s a lot of stigma around the condition, which can be hard for people who have it. They might feel uncomfortable when people stare at their lesions or avoid touching them, and they may try to hide their outbreaks under long clothing.

If you have psoriasis, you can help put an end to confusion and misunderstandings about the disease by talking openly with friends, family, and co-workers. And if you know people who have it, make sure they know that their condition doesn’t affect your opinion of them or make you not want to be around them.

Psoriasis affects up to 7.5 million Americans, according to the National Institutes of Health. Psoriasis is more common in adults than children and affects males and females equally.

Psoriasis affects:

• 2% to 3% of people throughout the world
• About 2.2% of people in the United States
• Some cultures more than others. Worldwide, psoriasis is most common in Scandinavia and other parts of northern Europe. It appears to be far less common among Asians and is rare in Native Americans, according to the American Academy of Dermatology.

What Are the Symptoms of Psoriasis?

The symptoms of psoriasisinclude:

• Areas of itchy, scaly skin on the scalp, knees, elbows, and upper body; these deep-pink, raised plaques of skin have white scales.
• Psoriasis on fingernails and toenails can make the nails become thick, pitted, and discolored; nails may separate from underlying nail bed.
• Red, scaly, cracked skin with tiny pustules on the palms of the hands and/or feet; you may have pustular psoriasis.

Symptoms of psoriatic arthritis include:

• Stiffness, pain, and tenderness of the joints
• Reduced range of motion
• Nail changes, such as pitting, which is found in up to 80% of people with psoriatic arthritis

Call Your Doctor About Psoriasis If:

Your skin inflammation does not respond to over-the-counter types of treatment; you need to be checked to see if more aggressive prescription topical and/or systemic therapy is needed.

How Severe Is Your Psoriasis?

If you’re wondering whether you have mild, moderate, or severe psoriasis, think about these three things:

• Body surface area: How much of your body has psoriasis? To figure this out, keep in mind that generally, your hand is equal to 1%.
• Severity: What’s the average scaling, thickness, and redness of your lesions? The more you have, the more severe your condition is.

Quality of life (QOL): How much does your psoriasis affect your daily life? Tools that measure this include questions about your condition, your skin, emotions, and relationships.

How You Find Out

Severity and body surface area are used together to calculate something called a Psoriasis Area and Severity Index (PASI) score. It combines the severity and surface area for six regions of your body. Scores range from 0 to 72. A score of more than 10 generally translates to “moderate-to-severe.” A score of more than 40 is rare.

Usually, the higher your PASI score, the lower your quality of life.

Your doctor may use one of three surveys to figure out how your psoriasis affects your quality of life:

• Psoriasis Index of Quality of Life (PSORIQoL): This tool focuses on how psoriasis changes how you deal with the needs of daily life. Questions cover things like sleep, your social life, and emotions.
• Psoriasis Life Stress Inventory (PLSI): It’s a 15-item questionnaire that asks you how stressful various daily tasks are for you.
• Psoriasis Disability Index (PDI): The PDI looks at how psoriasis affects your daily activities, including work, leisure time, and personal relationships.

What Makes It Mild, Moderate, or Severe?

In general, mild psoriasis means less than 3% of your body is affected. This typically means you have isolated patches on your limbs and on your scalp. Psoriasis is also considered mild if a skin medication controls it or if it only affects your quality of life a little bit.

Moderate psoriasis is when 3% to 10% of your body has patches. This usually means it affects your arms and legs, torso, and scalp. It’s also considered moderate if it can’t be controlled using a skin medication or if it has a significant impact on your quality of life.

If more than 10% of your body is affected, or if large areas on your face, palms or soles of your feet have patches, you have severe psoriasis. It can also be deemed severe if it can’t be controlled using a skin medication or it has a severe impact on your quality of life.

Why You Need to Know

Knowing whether your psoriasis is mild, moderate, or severe will help you find the best treatment. It’ll also let your doctor know whether the psoriasis is getting worse and how well your treatment is working.

Your doctor may use the PASI score to measure your progress. For example, if you hear you’re “PASI 75,” that means your PASI score has dropped by 75%.

Mild to moderate psoriasis means that the red, scaly patches (“plaques”) cover less than 10% of your body. But just because your psoriasis is called “mild” doesn’t mean it’s easy to live with. If the patches are in visible places like your hands or legs, you may be embarrassed to go out without wearing long sleeves and pants. Also, small areas of psoriasis can turn into big problems if they’re itchy or painful.

Your goal is to have clearer skin. To do that, you and your doctor need to find the right psoriasis treatment.

How Your Doctor Chooses Your Psoriasis Treatment

Each person with psoriasis is different. That’s why your doctor will use a few factors to decide which treatment to try:

• The type of psoriasis you have
• How much of your skin is covered
• How big of an impact psoriasis has on your life
• Your health

Your doctor may use the Koo-Menter Psoriasis Instrument to help decide on a treatment. This one-page tool asks questions to find out how much psoriasis affects your life. The doctor can use your answers to determine whether you need a skin cream, light therapy, or a drug that works throughout your body.

Usually doctors start with the mildest treatments for people with mild-to-moderate psoriasis. Often the first treatment you’ll try is a skin cream or ointment. If a mild treatment doesn’t work, you’ll move up to stronger treatments until your doctor finds one that helps you.

In general, you should not apply topical medications to open and infected areas, so speak with your doctor if your skin plaques become actively inflamed.

Corticosteroids

What it is: Corticosteroids, or steroids, are the most commonly used topical treatment for psoriasis.

How it works: Steroid drugs curb the growth rate of skin cells and reduce inflammation.

Types of corticosteroids: There are a variety of steroid creams, gels, lotions, and shampoos. They range from weak to strong. The stronger the steroid, the more effective it is. However, stronger steroids also cause more side effects.

Lower-strength steroids are best for treating sensitive areas for limited periods of time, like the face, groin, and breasts.
Higher-strength steroids are best for areas of the skin that don’t clear up with milder steroids or areas with thicker plaques.

Side effects include thin skin, changes in skin color, acne, stretch marks, redness, more visible blood vessels, or increased risk for infection. Although uncommon, topical steroids can be absorbed into the circulation and also cause side effects such as cataracts, glaucoma, and Cushing’s syndrome. These uncommon side effects are more likely to occur if you use very high strength topical steroids over a large area for extended period of time.

Vitamin D Analogues

What it is: A form of synthetic vitamin D that you rub on your skin.

How it works: Vitamin D creams slow skin cell growth.

Vitamin D creams include:

Calcipotriene (Dovonex, Sorilux, Taclonex)
Calcitriol (Vectical)

Side effects include skin irritation, burning, itching, dry skin, peeling skin, or rash. In rare cases, too much vitamin D can be absorbed into the body, which can lead to increased levels of calcium.

Retinoids

What it is: A man-made form of vitamin A.

How it works: It slows skin cell growth and reduces inflammation.

Types of topical retinoids:

Tazarotene (Tazorac) cream

Side effects include skin irritation, redness, and sensitivity to sunlight (you need to wear sunscreen while using this medicine). Let your doctor know if you are pregnant or might become pregnant, because this medicine may harm an unborn baby.

Anthralin

What it is: A man-made form of a substance that comes from the South American araroba tree.

How it works: It slows the growth of skin cells.

Types of anthralin:

Dritho-Scalp
Drithocreme
Micanol
Zithranol-RR

Side effects include skin irritation. It can also leave brown stains on clothes, hair, bed sheets, and skin.

Salicylic Acid

What it is: The same type of medicine that is used to treat acne.

How it works: Salicylic acid lotions, gels, and shampoos lift scales and help to remove them. Sometimes salicylic acid is used with other psoriasis treatments, such as corticosteroids or coal tar.

Side effects include skin irritation and hair loss.

Coal Tar

What it is: Coal tar is one of the oldest treatments for psoriasis.

How it works: Coal tar shampoos, creams, and lotions slow the growth of skin cells. They also reduce scaling, itching, and swelling. The Goeckerman treatment, once widely used, combines coal tar with light therapy. It has fallen out of favor due to its inconvenience.

Side effects include skin irritation and sensitivity to sunlight. Coal tar can also cause strong odor and staining of clothing, bed linens, or hair.

Other Over-the-Counter Treatments

A few other over-the-counter remedies can help treat psoriasis, including:

• Moisturizers containing aloe vera, jojoba, zinc pyrithione, or capsaicinsoften skin and relieve itching.
• Bath solutions containing oil, oatmeal, or Dead Sea salts can help remove scale.
• Scale lifters containing salicylic acid, lactic acid, or urea also remove scale.
• Anti-itch creams containing calamine, hydrocortisone, camphor, or menthol can help relieve itching.

Always discuss medications with your doctor, including over-the-counter remedies, to see if they are right for you. Your doctor may also recommend light therapy or an injected drug called a biologic that works throughout your body if your psoriasis is bothering you or having a big impact on your life.​

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