Treat PHOTOsensitivity reactions

Abdelwahab Ward, BS Pharm, PharmD

As a hospital pharmacist, you will be asked more about how to treat photosensitivity reactions. Warmer weather will bring questions about photosensitizing medications. Photosensitivity reactions are due to a combination of UV light with a medication or metabolite in the skin and are hard to predict. Response varies and evidence is mostly from case reports.

Be prepared when treating patients in the emergency department (ED) or giving discharge education to patients on photosensitizing medications...

  • Which medications cause photosensitivity?
    • Be familiar with common culprits, antibiotics (quinolones, sulfonamides, tetracyclines), voriconazole, and cardiovascular (CV) medications (amiodarone, thiazides).
    • Be aware, NSAIDs are also implicated to varying degrees.
      • For example, naproxen seems to be a more common trigger than ibuprofen.
      • Explore this resource, Drug-Induced Photosensitivity, for other examples, such as amitriptyline, glipizide, and topical retinoids.
  • What do reactions look like?
    • Expect most to appear similar to an exaggerated sunburn on exposed skin. These “phototoxic” reactions may be dose-related and develop within minutes to hours of light exposure.
    • Also be alert for less common “photoallergic” reactions, which look like eczema. These are NOT dose-related, develop a day or two after light exposure and might spread beyond sun-exposed skin.
  • How should reactions be treated?
    • Recommend cool compresses, topical or oral corticosteroids or oral antihistamines, depending on severity of the reaction.
    • Try to stop or switch the culprit medication and reemphasize preventive measures.
    • For phototoxic reactions, if a switch isn’t possible, consider lowering the medication dose, since reactions are often dose-related.
  • How can risk of photosensitivity be reduced?
    • Advise avoiding UV exposure, even through windows, if possible, regardless of skin type.
    • Emphasize protective clothing and a broad-spectrum sunscreen with UVA and UVB protection.

References

  1. Montgomery S, Worswick S. Photosensitizing drug reactions. Clin Dermatol. 2022 Jan-Feb;40(1):57-63.
  2. Blakely KM, Drucker AM, Rosen CF. Drug-Induced Photosensitivity-An Update: Culprit Drugs, Prevention and Management. Drug Saf. 2019 Jul;42(7):827-847.
  3. Di Bartolomeo L, Irrera N, et al. Drug-Induced Photosensitivity: Clinical Types of Phototoxicity and Photoallergy and Pathogenetic Mechanisms. Front Allergy. 2022 Jun 20;3:876695.
Abdelwahab Ward, BS Pharm, PharmD