In the course of treating and listening to patients, Dr. Viksman is asked many interesting questions. Here are a few with answers that you may find helpful.
Two of my children get a rash from sunscreen. They’re going away to summer camp and I’m worried that they’ll be unprotected in the summer sun. For some reason, they seem to be able to handle Neutrogena 30 but get a terrible rash from Neutrogena 45. What could be the difference between 30 and 45? What does the higher number do that creates this allergy?
Skin reaction to sunscreen products is common and could affect 15 to 20 percent of individuals that use them. Allergic reactions that are based on the immune system function are less common. Many skin rashes such as photoallergic contact dermatitis, allergic contact dermatitis, irritant contact dermatitis, contact urticaria, acneiform eruptions, and polymorphic light eruption (just to mention a few) are associated with using sun block products.
Only allergic contact dermatitis and photoallergic contact dermatitis are the result of an immune system response to sunscreen substances. The remainder of reactions is a result of sensitive skin reaction to nonspecific irritants. In the latter, you would simply monitor which sunscreens seem to be causing this reaction, and eliminate it as an option. Thankfully, there are many products available in today’s market. Certain children are sensitive and reactive to some, but not to others. Often, only the process of trial and elimination determines which ones would be a good match for each child. We also have to keep in mind that a higher sun protection factor (SFP) requires a stronger presence of active ingredients and leads to a higher probability of sunscreen dermatitis.
Both the active and inactive ingredients of the sunscreen could trigger allergic and nonallergic skin reactions. Allergic contact dermatitis is the least common reaction (less than 1 percent) and is related to direct allergic sensitization of the skin, similar to a poison ivy or poison oak reaction. Photoallergic contact dermatitis is a result of activation by ultraviolet radiation of sunscreen chemicals that eventually lead to allergic hypersensitivity and skin eruption. In fact, sunscreen substances are the most common cause of photoallergic contact dermatitis.
Photopatch and patch tests can diagnose both photoallergic contact dermatitis and allergic contact dermatitis to sunscreen products.
We moved from Pennsylvania to New Jersey a couple of years ago. My husband is in his late fifties, and he never had a sniffle in the spring – until we moved. At first we thought maybe it was the dust from packing and unpacking, but now, a year later, all the symptoms are back, so we think it must be spring allergies. I didn’t realize adults could develop allergies like this so late in life?
It is not very common to develop allergy in one’s late fifties, but it is nonetheless quite possible. A person whose immune system functions normally can develop an allergy later in life because an allergic response is part of the immune system reactivity. It usually takes a few years to develop allergy to pollens. There is no significant difference between pollinating trees in Pennsylvania and New Jersey, but density of various pollens in the air could be different from that in PA. This factor may contribute to stronger allergic response in a person living in NJ as compared to a PA resident.
When I was a child, at about age 10, I had an allergic reaction to the antibiotic Minocin. Nothing terrible happened; I just broke out in a rash from head to toe. I don’t know if anyone uses this antibiotic anymore. Now I’m nearing almost 50 years old, and whenever I’m asked if I’m allergic to any drugs, I always announce that I am allergic to Minocin. If I had an allergic reaction to a drug forty years ago, am I still considered “allergic” to this drug? And does anyone ever use this drug anymore anyway?
Minocycline (brand name is Minocin) is a tetracycline type of antibiotics. It is a less allergenic class of antibiotics than antibiotics belonging to penicillin family or sulfa drugs, but it can still trigger an allergic reaction. In fact, any medication can trigger an allergic reaction. It also worth remembering that allergy tends to fade with years of avoidance of the medication responsible for the allergic reaction. However, it is difficult to determine whether the allergy is completely gone without first conducting a special test/challenge. On the other hand, not every adverse reaction to a medication has an immune mechanism so as to be considered an allergic reaction.
Skin rash is the most common manifestation of allergic reaction to the medication, but not every drug rash has an allergic nature. For example, it is well known that the use of Amoxicillin or Ceclor during upper respiratory viral infection could trigger a rash that is not a result of allergic reaction. A repeated use of these antibiotics for treatment of other health conditions often does not reproduce skin rash.
My thirteen-year old daughter broke out in hives. She’s completely healthy otherwise. The doctor said that some kids break out in a rash for unknown reasons, probably a virus, and if it doesn’t pass, and Benadryl doesn’t work, we should see you, an allergist, and consider steroids. If she were feeling ill, I’d be more inclined to get her an allergist, but she isn’t, and I don’t want to start her on the road of steroids.
Hives, also known as “urticaria,” is a very common skin condition. Hives are divided into two major categories: acute and chronic.
Acute hives usually disappear in six weeks and represent a systemic allergic reaction. They can also be triggered by viruses, food, injected environmental allergens, medication, and bee venom. One must be allergic, or “sensitized,” to these substances to react with hives.
Soap, detergents, and other contact agents usually trigger contact dermatitis or contact allergic dermatitis but seldom cause generalized hives.
Acute hives form when allergens activate sensitized mast cells of the skin. These cells are packed with histamine and other biologically active products released upon mast cell activation.
If activated mast cells are located in the skin, we observe hives – also known as a “wheal-and-flare reaction” – with intensive itchiness. If activated cells are also located under the skin, we may observe a swelling of tissues – or “angioedema” – as well.
Hives lasting longer than six weeks are usually unrelated to allergy. About 40 to 50 percent of chronic urticarial rashes have an autoimmune nature. Many cases of chronic hives are triggered by physical factors such as pressure, cold water, overheating, exposure to sun, deep water, etc.
Treatment of hives and chronic hives in particular, is often challenging. Doctors usually prescribe higher than usual and different combinations of antihistamine preparations.
Resistant hives occasionally require systemic steroids, and a short course of oral steroids rarely causes serious side effects. Skin or blood testing may reveal the cause of hives, but this procedure makes sense only with acute urticaria. If resistant to antihistamines, chronic hives require treatment, blood work, urine tests, and subsequently steroids. The reason for such tests is to rule out the possibility of serious internal disorders, such as autoimmune diseases and malignant diseases of the
blood and rare solid organs. In most cases, results are within the normal range.
To summarize, acute hives are usually easy to treat and resolve quickly. Chronic hives require combination therapy, medication, and occasionally immunosuppressive therapy. Patients with chronic hives often relapse even years after initial episodes, and 20 percent could still have hives twenty years later.
The outcome of chronic Urticaria has been markedly improved with a recent introduction of injections of a Biologic product, Xolair (Omalizumab). The Biologic injections are usually delivered subcutaneously once a month.