By Shannon Foster, MD
Dermatology, 5th Floor
According to the National Psoriasis Foundation, up to 10 percent of the population has inherited one or more genes that make them susceptible to developing psoriasis. However, only about 2 to 3 percent of the population ever develop signs of the disease because an environmental trigger is considered necessary to activate those genes. A good example is a strep throat infection which can cause the genes to make inappropriate levels of growth factors that lead to psoriasis.
Disease can be widespread or confined to just the scalp, nails, or only the palms/soles. Common patterns are thick, red or white scales on the elbows/knees, or a plaque at the back of the scalp. Generally mild cases are treated with topical steroid creams that help decrease the inflammatory signals causing the skin to thicken and become red. Natural sunlight and ultraviolet treatments in the dermatology office are often helpful. Some cases that are resistant to external treatments need to be treated with oral or injectable medications. Most of these work by blocking an inflammatory molecule in the psoriasis-forming pathway. These medications are associated with rare, severe side effects so a discussion about risks and benefits is needed before deciding if they are right for each individual.
Pills available to treat psoriasis include Methotrexate, Cyclosporine, Soriatane and Otezla. Otezla is the newest drug that works in a way no other psoriasis drugs work. I have found it helpful in some cases of palm/sole disease, but it is less predictable for other types of psoriasis. It does not require any lab follow-up and the side effect profile is generally benign (diarrhea, depression). The injectable medications given at home such as Enbrel, Humira, Stelara and Cosentyx are also very effective. Remicade is given in IV form in an infusion center. Typically newer medications cost more and are less likely to be covered by insurance.
When your doctor prescribes a psoriasis medication, it usually has to go through a pre-approval process. Many times the insurance will only pay if the psoriasis covers more than 10 percent of the body surface or if multiple other medications have failed to produce improvement.
Arthritis can also go hand-in-hand with skin psoriasis. This is called psoriatic arthritis and depending on the medical study you consult, about 5 to 20 percent of patients with skin psoriasis will develop joint psoriasis too. Many of the pills and injectable medications also work for treatment of joint disease. It is important to note the severity of skin psoriasis doesn't always correlate with the severity of joint disease. Many patients with almost no skin disease will have severe joint symptoms and vice-versa. Nail psoriasis often correlates very highly with joint disease. Often your Dermatologist will work with a rheumatologist to decide which medication is best.
It is important to manage the inflammation of psoriasis aggressively because newer studies have linked this inflammation to an increased risk of heart disease and stroke. Some early evidence suggests the systemic medications may help combat these risks.
Improvements in psoriasis have also been seen with weight loss, smoking cessation, a healthy diet, and successful management of other
conditions such as diabetes, depression, high cholesterol or low Vitamin D levels. If you suspect you might have psoriasis, make an appointment with a dermatologist. Before your appointment, take a look at the National Psoriasis Foundation website and call your insurance provider to find out which treatments are covered on a first-line basis so you know your options. This helps streamline the process of starting you on appropriate medication.