Photoallergic eczema

Last Updated: 2023-07-07

Author(s): Anzengruber F., Navarini A.

ICD11: EK01

Photoallergic, photoallergy

In people with specific sensitisation to a certain allergen, dermatitis develops after contact sensitisation in the case of re-exposure.

As with other contact allergies, sensitisation is necessary first. With renewed exposure and UV-A radiation (less or rarely UV-B), photoallergic dermatitis develops.

Sharp, erythematous papules and papulovesicles. In some cases, blisters may also appear if the reaction is severe. A chronic photoallergic contact eczema may develop if the reaction persists.

  • Anamnesis
  • Clinic
  • Photopatch test
  • Photoprovocation

UV-exposed areas

Parahyperkeratosis, acanthosis, spongiosis, perivascular infiltrate.

UV protection

Contact allergy lasts a lifetime. However, after eliminating the photoallergen, exacerbation can be prevented.

  1. Onoue S, Seto Y, Sato H, Nishida H, Hirota M, Ashikaga T, Api AM, Basketter D, Tokura Y. Chemical photoallergy: photobiochemical mechanisms, classification, and risk assessments. J Dermatol Sci. 2017 Jan;85(1):4-11.
  2. Mowad CM, Anderson B, Scheinman P, Pootongkam S, Nedorost S, Brod B. Allergic contact dermatitis: Patient management and education. J Am Acad Dermatol. 2016 Jun;74(6):1043-54.