Often misunderstood as an ordinary skin disease, psoriasis is a condition where patients develop patches of red skin, often called lesions, covered with flakey dead skin cells. While the lesions commonly appear on the scalp, knees, elbow and torso, the condition may manifest itself differently in different people.

A large number of people do not acknowledge the condition or refrain from seeking treatment for it because of a number of misconceptions associated with it. Here, Dr. Sara Ferguson, a dermatologist at Penn State Medical Group in State College will help bust five such myths about psoriasis, providing a better understanding for those who need help.

Psoriasis is a skin disease.

In reality, psoriasis is an autoimmune disease that causes multi-system inflammation, and can affect the joints. Those suffering from the disease are also exposed to higher risks of developing heart disease, high blood pressure, diabetes, depression, psoriatic arthritis, inflammatory bowel disease and obesity, among others.

While the extent of the skin lesions may differ from small patches for some to almost the entire skin for others, the patients must regularly consult a physician regarding the accompanying risks.

Psoriasis is rare.

Even though the National Psoriasis Foundation puts the number of people suffering from the disease in the United States at approximately 7.5 million, Dr. Ferguson explains that the disease affects two to five percent of the population — 16 million Americans —many of whom do not seek treatment because of mild symptoms.

Psoriasis is contagious.

Many fear that the disease can be contracted by touch and use this as an explanation for why psoriasis runs in families but in reality, it is not an infection. There is no virus or bacteria involved, and some develop it because of inherited genes, which when exposed to external triggers like infection or skin injury can cause psoriasis.

No can help with the condition.

There was a time when the treatment for the disease was limited, leaving many patients frustrated. However, a number of new treatments are now available and it is recommended that patients discuss the newer options with their dermatologist to decide what can work best for them.

Topical creams are the only available treatment for psoriasis.

For mild to moderate psoriasis, corticosteroids, vitamin D, anthralin, coal tar and salicylic acid can be applied to the skin. Another option is phototherapy, where the skin is exposed to ultraviolet light on a regular basis. Medical supervision is essential for this.

Patients can also turn to regular systemic treatments like acitretin, cyclosporine and methotrexate — taken by mouth, injection or infusion. Protein-based drugs that target specific parts of the immune system like recently developed versions of TNF-alpha blockers, and a new classes of drugs like IL-17 inhibitors can also prove to be helpful.