True photoallergy to sunscreens is rare despite popular belief.

BACKGROUND: Rising use of sunscreen products has led to increased reporting of adverse reactions to sunscreens. OBJECTIVE: To investigate possible photoallergic reactions in patients who identified themselves as "being allergic" to sunscreens. METHODS: Patients filled out questionnaires about types of sunscreens they used and timing of their "allergic" reactions. Next, they consented to be photopatch-tested with active sunscreen ingredients, including the new sunscreen Anthelios SX (containing Mexoryl SX) and the new ultraviolet filters Tinosorb M and Tinosorb S. Standard allergen patch testing was also done. RESULTS: Twenty-seven patients self-reported "sunscreen allergy." Photopatch testing is difficult for patients; hence, only 11 agreed to proceed with the testing. Eight patients had negative patch testing results. One patient reacted to benzophenone-2. Another had a prior reaction to titanium dioxide and titanium oxalate but did not react to the silicone-coated titanium in our study. Yet another patient had relevant photopatch reactions to benzophenone-3 and ethylhexyl dimethyl para-aminobenzoic acid (PABA). None reacted to the Tinosorbs or Anthelios SX. Few positive reactions to the standard allergens were not relevant. CONCLUSION: Although small, this study parallels prior studies in concluding that true delayed type IV hypersensitivity (allergic contact dermatitis and photoallergy) to sunscreens is more infrequent than patients tend to believe.

Allergic contact dermatitis from medical adhesive bandages in patients who report having a reaction to medical bandages.

BACKGROUND: Medical adhesive bandages are extensively used in both inpatient and outpatient medicine. However, few reports describing proven allergic contact dermatitis (ACD) from medical adhesive bandages exist in the literature. These reports do not adequately correspond to the frequency that patients report having an "allergy" to medical adhesive bandages. OBJECTIVE: To determine if there is a chemical present in medical adhesive bandages that causes ACD in people who identify themselves as having an "allergy" to medical adhesive bandages. METHODS: Twenty-six patients were enrolled and underwent patch testing with our standard trays (104 chemicals) and a customized adhesive tray (54 chemicals and 10 tapes and bandages in their whole form). RESULTS: We were able to identify an allergen in four patients that was related to their presumed adhesive allergy (Mastisol, neomycin/bacitracin [two different patients], and cortisone-10 cream, respectively). However, there were no positive allergic reactions to the tapes or bandages or any relevant allergic reactions to our customized adhesive tray. Eight (73%) of the 11 patients who had the bandage or tape left on for 7 days had an irritant reaction. CONCLUSION: We feel that the perceived reactions are not secondary to ACD but instead are due to an irritant contact dermatitis.