As a practicing pharmacist, I am often asked questions that patients would love to talk to their physicians about, but since I am more accessible, they often ask me. Recently, one of my psoriasis patients asked me if they have an increased risk for getting shingles because of their psoriasis. The short answer is: probably so. A better answer requires some detailed background work.
As you know, psoriasis is the result of a defect within a person’s immune system. They have an immune system disorder that causes their body to attack itself. This is where the term auto-immune disease comes from. The result of this immune disorder is the rapid build up of scaly tissue into plaques which can be seen as red to silvery in appearance with intense itching and possible painful inflammation of the skin. The skin cells do not follow a normal build up and shedding cycle which can last up to a month. The cycle is sped up dramatically to last only a few days. This is why the cells build up into plaques because they do not have enough time to follow a normal course of shedding.
Shingles, medically known as Herpes Zoster, is the result of activation of the varicella virus that a person contracted when they were younger. At that time, a person who came down with Chicken Pox, was infected with the varicella virus and upon getting over the disease, the virus never leaves the body but in fact becomes dormant. In this dormant state, the virus lives within the nervous system and stays that way for most individuals. Approximately one-third of patients who have the dormant varicella virus within their system will undergo activation of the virus into a case of shingles. So then the question becomes: “what caused this activation to happen”.
The two most common reasons why this happens are as follows. All your cells are protected by what is known as cell-mediated immunity. This feed back system takes into account several body systems which normally keeps you healthy. Just like everything else about your body, as you get older, systems break down and do not do as good a job as when you were younger. Therefore, it has been postulated that this cell-mediated immunity may not be working so well with age and hence the protection it affords will decline with time and allow for opportunistic bugs, (bacteria, virus, etc) to take hold.
The second reason why a dormant varicella virus might come out of hibernation and develop into shingles is because the patient may have an immune system disorder such as psoriasis. While there are many different immune system disorders, the point is that if your immune system has been compromised, once again it affords those opportunistic bugs to take over.
If you have psoriasis, it would behoove you to get your situation under control with medications, phototherapy, immuno-modulators or any other course of psoriasis treatment that you and your physician can arrive at.