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Psoriasis is common but misunderstood. Design by Diego Sabogal

Psoriasis is a relatively common immune-mediated skin condition. It causes crusty, flaky patches to appear on the skin, commonly on the knees, scalp, elbows, and back. These patches present as red on light skin and may appear violet or purple on dark skin.

Globally, the exact prevalence of psoriasis is difficult to ascertain. However, a 2020 study found that the prevalence varies from 0.14% of the population in East Asia to 1.99% in Australasia.

Aside from the physical aspects of psoriasis, the condition can affect people’s well-being and quality of life.

Similarly, some people with psoriasis face stigma. As the authors of one study write:

“Stigmatizing views of persons with psoriasis are prevalent among people in the United States. Educational campaigns for the public and medical trainees may reduce stigma toward persons with psoriasis.”

With this in mind, we address some persistent myths that surround psoriasis and enlist the help of two experts to debunk them.

The first is David Chandler, chief executive of the Psoriasis and Psoriatic Arthritis Alliance in the United Kingdom. The second is Dominic Urmston, patient advocacy and communications manager at the Psoriasis Association, also in the United Kingdom.

Although this myth is pervasive, it is still a myth. As Chandler explained:

You cannot catch psoriasis. It is an autoimmune condition where the immune system responds inappropriately and produces too many skin cells.”

To stress the point further, Urmston told Medical News Today:

“It cannot be caught by person-to-person contact or by sharing of bodily fluids — for instance, by kissing or sharing food or drinks. It also cannot be caught by others in close contact public areas, such as in swimming pools or in saunas.”

No, it’s much more than that,” Chandler said.

“The skin structure turns over much quicker — the usual skin turnover is around every 28 days, [but] in psoriasis, it can be as short as 4–5 days.

Due to this short turnaround, the skin cells have not yet matured. They build up into thick scales, which the body cannot shed as usual.

In addition, Chandler explained, “Blood vessels also change and move closer to the surface, which causes the areas, if scratched, to bleed, becoming very red and sore.”

“In more severe cases, psoriasis can cause the skin to crack and bleed, which can be debilitating,” Urmston said.

“Psoriasis on the hands or feet can make everyday activities difficult, and psoriasis on areas such as the groin or buttocks can make even sitting down or going to the toilet painful.”

There is a common misconception that psoriasis is psoriasis, and there is no variation. However, this is not the case.

“The most common type,” explained Chandler, “is large plaque psoriasis with typical thick silvery scales.” Other types include:

  • Guttate psoriasis: People sometimes describe guttate psoriasis as “raindrop psoriasis” because the scaly patches are tear-shaped.
  • Inverse psoriasis: This type only forms in regions that make contact with other parts of the body, such as the armpits, groin, or area under the breasts.
  • Erythrodermic psoriasis: This uncommon type of psoriasis involves a peeling rash that covers much of the body.
  • Pustular psoriasis: In this type, pus-filled bumps develop, most commonly on the hands and feet.

The presence of psoriasis does not mean that a person’s hygiene is poor,” confirmed Urmston.

“No, definitely not,” Chandler concurred.

“In fact, people with psoriasis tend to have to be scrupulous about self-care, as the skin is so sore and flaky that it needs constant care.”

He also explained that people with psoriasis often have to use their treatments twice each day, meaning that “people will spend a great deal of time managing it, particularly [in] areas such as the scalp, because if it is left, it will become very difficult to manage very quickly.”

This is another myth, as currently, there is no cure for psoriasis. However, scientists are continuing to develop their understanding of the condition, and, as Chandler noted, this new understanding “may lead to a cure at some stage in the future.”

Importantly, as Urmston pointed out, “psoriasis can be successfully treated and managed, and doctors and dermatologists can offer a wide range of treatment options.”

The condition’s effect on the skin is the most noticeable, but psoriasis is not just skin-deep. As Urmston told MNT:

“Psoriasis can affect more than just the skin.” An estimated 6–42% of people with psoriasis also develop psoriatic arthritis, which Urmston describes as “an inflammatory arthritis that affects the joints. It often affects the knees or the joints in the hands and feet — as well as areas where tendons join to bone, such as the heel and lower back.”

Beyond its physical effects, psoriasis can have a psychological impact, too.

“People with psoriasis are also more likely to experience anxiety, depression, and low confidence and self-esteem,” explained Urmston, “which can all have a significant impact on day-to-day life.”

Although there is no cure, it is a myth that there are no treatment options.

“There are numerous treatments that can help relieve the symptoms of psoriasis, depending on how badly the individual is affected,” Chandler stated.

“These range from topical (applied) creams to ointments, foams, and gels. Light therapy is also used, as are disease-modifying drugs both as tablet[s] and injection[s] — all having varying benefits and associated risks.”

As psoriasis is a chronic condition that lasts a lifetime, a person may need to work with their doctor to modify their treatment plan over time.

“Most people with psoriasis start their treatment under the guidance of a doctor who can prescribe topical (applied to the skin) treatments in different formulations (creams, ointments, and gels).

“If psoriasis is more severe, or if various types of topical treatments are ineffective, a doctor should provide a referral to a dermatologist, who can offer further treatment options, such as UV light therapy and tablet and injection treatments.”

— Dominic Urmston

“Although most commonly seen in adults — psoriasis often starts in teenage years and lasts a lifetime — it can be seen in children and also, rarely, in babies,” explained Chandler.

Urmston told MNT that “there seem to be two ‘peaks’ of onset: from the late teens to early 30s and between the ages of about 50 and 60.”

Although the primary symptoms of eczema and psoriasis are both dermatological, the conditions are entirely different.

As Chandler explained, “Eczema is often based on an allergic reaction, which psoriasis is not.” Also, eczema is “more common in young children and can disappear over time.” Conversely, psoriasis is less common in children and tends to be a lifelong condition.

“They also tend to affect different areas of the body,” said Urmston, “with eczema tending to appear inside the elbows and knees (the crook), whereas psoriasis appears more frequently on the outside of the elbows and knees, as well as on the scalp.”

Overall, the underlying mechanisms that drive eczema and psoriasis are different, too. Psoriasis is an autoimmune condition, whereas eczema can involve genetic, environmental, and other factors. However, there is some evidence to suggest that eczema can be an autoimmune condition, as well.

Importantly, Urmston stated, “With both conditions, a diagnosis from a trained healthcare professional is vital in order to begin the most relevant treatment pathway as early on in the course of the condition as possible.”

“There is no evidence to suggest a particular diet can cure psoriasis,” Chandler told MNT.

“Many people may associate changes in diet with an improvement, but as the nature of psoriasis is to ‘wax and wane,’ this could be a coincidental occurrence.”

However, he also said that “following a healthy, well-balanced diet, keeping weight down, and exercising regularly are generally good pieces of advice to follow for overall well-being.”

In agreement, Urmston told MNT:

“At this time, there is a lack of robust research linking any specific change in diet to an improvement in psoriasis symptoms. We do know that factors such as obesity, alcohol, and smoking can increase the severity of psoriasis symptoms, so a healthy lifestyle, including regular exercise and a healthy, balanced diet, can be beneficial in managing psoriasis.”

Psoriasis is not curable, but it is treatable. Anyone who believes that they might have psoriasis should speak with a doctor so that they can begin treatment as soon as possible.

As with all medical conditions, researchers continue to investigate ways in which it might be possible to manage the symptoms more effectively. One day, scientists may also develop a cure.

Read this article in Spanish.