What is psoriasis
Psoriasis is a chronic autoimmune condition that causes the rapid buildup of skin cells. This buildup of cells causes scaling on the skin’s surface.
Inflammation and redness around the scales is fairly common. Typical psoriatic scales are whitish-silver and develop in thick, red patches. Sometimes, these patches will crack and bleed.
Psoriasis is the result of a sped-up skin production process. Typically, skin cells grow deep in the skin and slowly rise to the surface. Eventually, they fall off. The typical life cycle of a skin cell is one month.
In people with psoriasis, this production process may occur in just a few days. Because of this, skin cells don’t have time to fall off. This rapid overproduction leads to the buildup of skin cells.
Scales typically develop on joints, such elbows and knees. They may develop anywhere on the body, including the:
- hands
- feet
- neck
- scalp
- face
Less common types of psoriasis affect the nails, the mouth, and the area around genitals.
According to one study, around 7.4 million Americans have psoriasis. It’s commonly associated with several other conditions, including:
What are the different types of psoriasis?
There are five types of psoriasis:
Plaque psoriasis
Plaque psoriasis is the most common type of psoriasis.
The American Academy of Dermatology (AAD) estimates that about 80 percent of people with the condition have plaque psoriasis. It causes red, inflamed patches that cover areas of the skin. These patches are often covered with whitish-silver scales or plaques. These plaques are commonly found on the elbows, knees, and scalp.
Guttate psoriasis
Guttate psoriasis is common in childhood. This type of psoriasis causes small pink spots. The most common sites for guttate psoriasis include the torso, arms, and legs. These spots are rarely thick or raised like plaque psoriasis.
Pustular psoriasis
Pustular psoriasis is more common in adults. It causes white, pus-filled blisters and broad areas of red, inflamed skin. Pustular psoriasis is typically localized to smaller areas of the body, such as the hands or feet, but it can be widespread.
Inverse psoriasis
Inverse psoriasis causes bright areas of red, shiny, inflamed skin. Patches of inverse psoriasis develop under armpits or breasts, in the groin, or around skinfolds in the genitals.
Erythrodermic psoriasis
Erythrodermic psoriasis is a severe and very rare type of psoriasis.
This form often covers large sections of the body at once. The skin almost appears sunburned. Scales that develop often slough off in large sections or sheets. It’s not uncommon for a person with this type of psoriasis to run a fever or become very ill.
This type can be life-threatening, so individuals should see a doctor immediately.
Check out pictures of the different types of psoriasis.
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.
Is psoriasis contagious?
Psoriasis isn’t contagious. You can’t pass the skin condition from one person to another. Touching a psoriatic lesion on another person won’t cause you to develop the condition.
It’s important to be educated on the condition, as many people think psoriasis is contagious.
What causes psoriasis?
Doctors are unclear as to what causes psoriasis. However, thanks to decades of research, they have a general idea of two key factors: genetics and the immune system.
Immune system
Psoriasis is an autoimmune condition. Autoimmune conditions are the result of the body attacking itself. In the case of psoriasis, white blood cells known as T cells mistakenly attack the skin cells.
In a typical body, white blood cells are deployed to attack and destroy invading bacteria and fight infections. This mistaken attack causes the skin cell production process to go into overdrive. The sped-up skin cell production causes new skin cells to develop too quickly. They are pushed to the skin’s surface, where they pile up.
This results in the plaques that are most commonly associated with psoriasis. The attacks on the skin cells also cause red, inflamed areas of skin to develop.
Genetics
Some people inherit genes that make them more likely to develop psoriasis. If you have an immediate family member with the skin condition, your risk for developing psoriasis is higher. However, the percentage of people who have psoriasis and a genetic predisposition is small. Approximately 2 to 3 percent of people with the gene develop the condition, according to the National Psoriasis Foundation (NPF).
Read more about the causes of psoriasis.
Diagnosing psoriasis
Two tests or examinations may be necessary to diagnose psoriasis.
Physical examination
Most doctors are able to make a diagnosis with a simple physical exam. Symptoms of psoriasis are typically evident and easy to distinguish from other conditions that may cause similar symptoms.
During this exam, be sure to show your doctor all areas of concern. In addition, let your doctor know if any family members have the condition.
Biopsy
If the symptoms are unclear or if your doctor wants to confirm their suspected diagnosis, they may take a small sample of skin. This is known as a biopsy.
The skin will be sent to a lab, where it’ll be examined under a microscope. The examination can diagnose the type of psoriasis you have. It can also rule out other possible disorders or infections.
Most biopsies are done in your doctor’s office the day of your appointment. Your doctor will likely inject a local numbing medication to make the biopsy less painful. They will then send the biopsy to a lab for analysis.
When the results return, your doctor may request an appointment to discuss the findings and treatment options with you.
Psoriasis triggers: Stress, alcohol, and more
External “triggers” may start a new bout of psoriasis. These triggers aren’t the same for everyone. They may also change over time for you.
The most common triggers for psoriasis include:
Stress
Unusually high stress may trigger a flare-up. If you learn to reduce and manage your stress, you can reduce and possibly prevent flare-ups.
Alcohol
Heavy alcohol use can trigger psoriasis flare-ups. If you excessively use alcohol, psoriasis outbreaks may be more frequent. Reducing alcohol consumption is smart for more than just your skin too. Your doctor can help you form a plan to quit drinking if you need help.
Injury
An accident, cut, or scrape may trigger a flare-up. Shots, vaccines, and sunburns can also trigger a new outbreak.
Medications
Some medications are considered psoriasis triggers. These medications include:
Infection
Psoriasis is caused, at least in part, by the immune system mistakenly attacking healthy skin cells. If you’re sick or battling an infection, your immune system will go into overdrive to fight the infection. This might start another psoriasis flare-up. Strep throat is a common trigger.
Here are 10 more psoriasis triggers you can avoid.
Treatment options for psoriasis
Psoriasis has no cure. Treatments aim to reduce inflammation and scales, slow the growth of skin cells, and remove plaques. Psoriasis treatments fall into three categories:
Topical treatments
Creams and ointments applied directly to the skin can be helpful for reducing mild to moderate psoriasis.
Topical psoriasis treatments include:
- topical corticosteroids
- topical retinoids
- anthralin
- vitamin D analogues
- salicylic acid
- moisturizer
Systemic medications
People with moderate to severe psoriasis, and those who haven’t responded well to other treatment types, may need to use oral or injected medications. Many of these medications have severe side effects. Doctors usually prescribe them for short periods of time.
These medications include:
- methotrexate
- cyclosporine (Sandimmune)
- biologics
- retinoids
Light therapy
This psoriasis treatment uses ultraviolet (UV) or natural light. Sunlight kills the overactive white blood cells that are attacking healthy skin cells and causing the rapid cell growth. Both UVA and UVB light may be helpful in reducing symptoms of mild to moderate psoriasis.
Most people with moderate to severe psoriasis will benefit from a combination of treatments. This type of therapy uses more than one of the treatment types to reduce symptoms. Some people may use the same treatment their entire lives. Others may need to change treatments occasionally if their skin stops responding to what they’re using.
Learn more about your treatment options for psoriasis.
Medication for psoriasis
If you have moderate to severe psoriasis — or if psoriasis stops responding to other treatments — your doctor may consider an oral or injected medication.
The most common oral and injected medications used to treat psoriasis include:
Biologics
This class of medications alters your immune system and prevents interactions between your immune system and inflammatory pathways. These medications are injected or given through intravenous (IV) infusion.
Retinoids
Retinoids reduce skin cell production. Once you stop using them, symptoms of psoriasis will likely return. Side effects include hair loss and lip inflammation.
People who are pregnant or may become pregnant within the next three years shouldn’t take retinoids because of the risk of possible birth defects.
Cyclosporine
Cyclosporine (Sandimmune) prevents the immune system’s response. This can ease symptoms of psoriasis. It also means you have a weakened immune system, so you may become sick more easily. Side effects include kidney problems and high blood pressure.
Methotrexate
Like cyclosporine, methotrexate suppresses the immune system. It may cause fewer side effects when used in low doses. It can cause serious side effects in the long term. Serious side effects include liver damage and reduced production of red and white blood cells.
Learn more about the oral medications used to treat psoriasis.