Psoriasis is a skin disease that causes red, itchy scaly patches, most commonly on the knees, elbows, trunk and scalp.
There are several different types of psoriasis. These vary depending on the appearance of the scales and their location on the body. In the United States, over 8 million people have a form of psoriasis.
Environmental triggers often cause the symptoms of psoriasis to flare. Although it is not currently possible to cure these symptoms, recent developments in psoriasis treatments mean that it is possible to reduce the number of flares and their severity.
What Is Psoriasis?
Psoriasis is an immune-mediated disease* (a disease with an unclear cause that is characterized by inflammation caused by dysfunction of the immune system) that causes inflammation in the body. There may be visible signs of the inflammation such as raised plaques (plaques may look different for different skin types) and scales on the skin.
This occurs because the overactive immune system speeds up skin cell growth. Normal skin cells completely grow and shed (fall off) in a month. With psoriasis, skin cells do this in only three or four days. Instead of shedding, the skin cells pile up on the surface of the skin. Some people report that psoriasis plaques itch, burn and sting. Plaques and scales may appear on any part of the body, although they are commonly found on the elbows, knees, and scalp.
Inflammation caused by psoriasis can impact other organs and tissues in the body. People with psoriasis may also experience other health conditions. One in three people with psoriasis may also develop psoriatic arthritis. Signs of PsA include swelling, stiffness and pain in the joints and areas surrounding the joints. PsA often goes undiagnosed, particularly in its milder forms. However, it’s important to treat PsA early on to help avoid permanent joint damage.
Symptoms often start between ages 15 and 25, but can start at any age. Men, women, and children of all skin colors can get psoriasis.
What part of the body does psoriasis affect?
The rash can show up anywhere. In most people, it covers only a few patches of skin. In severe cases, the plaques connect and cover a large area of the body. Psoriasis can make you uncomfortable, itchy and self-conscious.
Psoriasis tends to affect the:
- Elbows and knees.
- Face, scalp and inside the mouth.
- Fingernails and toenails.
- Lower back.
- Palms and feet.
Other types of psoriasis include:
- Pustular psoriasis, which causes red and scaly skin with tiny pustules on the palms of the hands and soles of the feet.
- Guttate psoriasis, which often starts in childhood or young adulthood, causes small, red spots, mainly on the torso and limbs. Triggers may be respiratory infections, strep throat, tonsillitis, stress, injury to the skin, and taking antimalarial and beta-blocker medications.
- Inverse psoriasis, which makes bright red, shiny lesions that appear in skin folds, such as the armpits, groin, and under the breasts.
- Erythrodermic psoriasis, which causes fiery redness of the skin and shedding of scales in sheets. It’s triggered by severe sunburn, infections, certain medications, and stopping some kinds of psoriasis treatment. It needs to be treated immediately because it can lead to severe illness.
What Are The Symptoms?
Psoriasis symptoms differ from person to person and depend on the type of psoriasis. Areas of psoriasis can be as small as a few flakes on the scalp or elbow, or cover the majority of the body.
The most common symptoms of plaque psoriasis include:
- red, raised, inflamed patches of skin
- whitish-silver scales or plaques on the red patches
- dry skin that may crack and bleed
- soreness around patches
- itching and burning sensations around patches
- thick, pitted nails
- painful, swollen joints
Not every person will experience all of these symptoms. Some people will experience entirely different symptoms if they have a less common type of psoriasis.
Most people with psoriasis go through “cycles” of symptoms. The condition may cause severe symptoms for a few days or weeks, and then the symptoms may clear up and be almost unnoticeable. Then, in a few weeks or if made worse by a common psoriasis trigger, the condition may flare up again. Sometimes, symptoms of psoriasis disappear completely.
When you have no active signs of the condition, you may be in “remission.” That doesn’t mean psoriasis won’t come back, but for now you’re symptom-free.
Causes and Risk Factors
Psoriasis, in general, is a genetic condition passed down through families. “It’s likely that multiple genes need to be affected to allow psoriasis to occur and that it’s frequently triggered by an external event, such as an infection,” says James W. Swan, MD, professor of dermatology at the Loyola University Stritch School of Medicine in Maywood, Illinois.
According to the National Psoriasis Foundation (NPF), at least 10 percent of people inherit genes that could lead to psoriasis, but only 3 percent or less actually develop the disease. For this reason, it is believed that the disease is caused by a combination of genetics and external factors or triggers.
A psoriasis outbreak may be provoked by:
Stress is a major trigger for some people with psoriasis, either causing psoriasis to flare up for the first time or to make it worse after you’ve been diagnosed.
“Psoriasis is very stress-dependent. It flares very easily when patients are under stress, and it tends to improve when they’re relaxed,” says Vesna Petronic-Rosic, MD, a dermatologist and associate professor of medicine at the University of Chicago Medicine in Illinois. Stress management techniques, such as exercise, yoga, and meditation, may help manage psoriasis symptoms.
A trip to the Caribbean might be a good idea during the winter months if you have psoriasis and live in a cold climate. That’s because the sun’s ultraviolet light turns off the skin’s immune system, which is overactive in people with psoriasis. Check with your dermatologist before traveling for sun safety skin tips and limit your daily exposure to no more than 10 minutes of direct sunlight.
Anything that injures the skin can cause a psoriasis flare, including excessively dry skin.
The solution: Keep your skin moisturized. If you’re allergic to the fragrances in moisturizers, use a product that’s fragrance-free to avoid a rash.
As with dry skin, puncturing the skin during a vaccination may cause a psoriasis flare, but that’s no reason to skip a needed shot.
One thing to keep in mind: If you’re on a potent psoriasis medication that suppresses your immune system (such as a biologic treatment), you shouldn’t take a live vaccine. Your body may not be able to fight off a live virus because of the medication you’re taking. In that case, ask your doctor for a vaccine that contains a deactivated virus.
Beta-Blockers and Lithium
Beta-blockers to treat high blood pressure and lithium for a mental disorder can make psoriasis worse.
If you have high blood pressure, your doctor may be able to switch your medication to another drug that won’t affect the psoriasis. If you’re taking lithium, your dermatologist may consider having you try light therapy or a topical treatment for psoriasis.
Upper Respiratory Infections
Colds and other infections, especially strep throat, activate the immune system and can cause psoriasis to flare. If you have psoriasis and develop a sore throat, get it treated and be sure to have a culture taken to check for strep. Long-term antibiotics may be an option for someone who has psoriasis and frequent sore throats.
There’s some evidence that smoking can make psoriasis worse. According to a study published in March 2012 in the American Journal of Epidemiology, smokers have almost double the risk of developing psoriasis compared with people who’ve never smoked. In a smaller study published in February 2016 in the International Journal of Dermatology that looked at twins, heavy smokers were more than twice as likely to have psoriasis.
Studies haven’t shown any beneficial effects of taking nutritional supplements for psoriasis, but avoiding certain foods may reduce inflammation and help with psoriasis. Additionally, studies have shown that many people with psoriasis may also have a gluten sensitivity, and eating a gluten-free diet can help reduce psoriasis symptoms. In general, if you find that a certain food makes the psoriasis worse, try to avoid it.
For some people with psoriasis, having more than one or two drinks a day has been shown to cause psoriasis flares, but the association is not a strong one. Flares from alcohol use could also be linked to psychological stress.
There are currently no blood tests that can confirm psoriasis, so a doctor will diagnose the condition by assessing a person’s rashes and lesions. The appearance of the symptoms may vary depending on the severity of the condition and the type of psoriasis the person has.
The doctor will examine the symptoms and ask about the individual’s personal and family history. They might also carry out a skin biopsy to rule out other conditions, such as eczema.
A person who has a persistent rash that does not resolve with over-the-counter (OTC) remedies may want to talk with a doctor. Often, recognizing and treating the symptoms early improves the long-term outcome associated with psoriasis.
Since psoriasis mainly affects the skin, topical treatments are very useful because they are relatively safe, fairly effective, and can be applied directly to the affected skin. They take the form of lotions, foams, creams, ointments, gels, and shampoos. They include topical steroids, tar preparations, and calcium- modulating drugs. The precise drug used and the form in which it is delivered depends on the areas involved. In widespread disease in patients with more than 10% of the body surface involved, it may not be practical to use topical medication alone.
For more extensive psoriasis, a useful option is ultraviolet (UV) light exposure. UV light can treat large areas of skin with few side effects, if performed in the physician’s office. It should be kept in mind that all UV light causes mutational events, which can lead to skin cancer. At this time, the most popular type of UV light for psoriasis is called narrow-band UVB. Only a small portion of the UV light spectrum is used, which seems to be particularly beneficial for psoriasis and may be less carcinogenic.
This UVB is quite different from UVA, the wavelength available in tanning salons, which is not effective against psoriasis. Phototherapy can be used alone or with medications when treating psoriasis.
Excimer lasers or pulsed dye lasers are used in laser therapy. A pulsed dye laser will create a concentrated beam of yellow light. When this light hits the skin, it converts to heat. The heat then destroys the extra blood vessels in the skin that contribute to psoriasis. Excimer lasers will deliver ultraviolet light to localized areas of the skin that help treat psoriasis. These lasers produce UV light in wavelengths similar to narrow-band UVB.
Laser therapy uses intense doses of laser light to help control areas of mild to moderate psoriasis without damaging surrounding healthy skin. These can be quite effective for small plaques of psoriasis, but since only small areas of skin can be treated at once, they are not practical for extensive disease.
There are a variety of drugs administered systemically that are useful in controlling psoriasis. As a generalization, most oral medications act by targeting portions of the immune system. One exception is a drug called acitretin (Soriatane), which is structurally similar to vitamin A.
Since your immune system is necessary for survival, systemic treatments do have a downside. Drugs like methotrexate and cyclosporine are administered orally and can affect your liver, kidney, and bone marrow. One oral medication called Otezla (apremilast) selectively targets molecules inside immune cells and adjusts (reduces) the processes of inflammation within the cell, which in turn helps treat psoriasis. This drug appears to be considerably safer than most of its predecessors but may also be more expensive.
A new class of drugs has recently been developed called biologics; they’re called biologics because living cells synthesize them. Since these drugs are proteins, they cannot be administered orally and must be given by injection through the skin or by an intravenous infusion (IV). This treatment is recommended in patients with moderate to severe psoriasis. These drugs target the immune response that leads to the rapid skin cell growth of psoriasis. This seems to have increased their safety profile as well as their effectiveness when compared to older drugs. However, they can be expensive.
There are many home remedies in the treatment of psoriasis. It is very important to keep the skin moist to avoid dryness. Petroleum jelly, vegetable shortening, or olive oil can be used as moisturizers. Take fewer showers and baths to avoid stripping the skin of its natural oils. Adding salts, oil, or finely ground oatmeal to a bath can soothe the skin. Heliotherapy (medicinal sunbathing) can be effective in controlling psoriasis. There is also evidence that increased body mass is associated with psoriasis and that heavier individuals are more difficult to treat.
It is not possible to avoid psoriasis flares. However, a person may be able to reduce their risk of flares by mitigating outside risk factors. These strategies can work alongside traditional treatment plans.
Some strategies include:
- reducing stress with yoga, exercise, and meditation
- eating a balanced diet
- recognizing and avoiding food triggers
- not smoking or drinking alcohol in excess
A person may also be able to use topical home remedies to reduce symptoms such as itching. They may do so by keeping the skin moisturized and avoiding hot, prolonged showers.
Although psoriasis can sometimes be isolating and uncomfortable, people have many options for managing the symptoms and treating the immune activity of the condition.