Berlock Dermatitis

Berlock dermatitis typically occurs on the neck, face, and breast, with drop-shaped or quadrilateral patches or streaks, induced by sequential exposure to perfume or other toilet articles and then to sunlight. Berlock or Berloque dermatitis obtains its name from the German word berlock or the French berloque, meaning trinket or charm. Rosenthal coined the term in 1925 to describe pendantlike streaks of pigmentation on the neck, face, arms, or trunk. He suspected they were due to fluid droplets, unaware that Freund in 1916 had described hyperpigmented macules due to sun exposure after the application of eau de cologne. The phototoxic ingredient causing the pigmentation proved to be bergapten, a component of oil of bergamot, derived from the rind of Citrus bergamia, the bergamot lime. Several cases were reported in the 1950s and 1960s following increased use of perfumes containing oil of bergamot and the passion for sunbathing. Since the introduction of artificial oil of bergamot and the reduced use of the natural product in perfumes, berloque dermatitis has become rare.