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August 1964

Contact Photodermatitis From Bithionol: II. Cross-Sensitivities to Hexachlorophene and Salicylanilides

Author Affiliations


Staff Member, Department of Dermatology, Hitchcock Clinic.

Arch Dermatol. 1964;90(2):153-157. doi:10.1001/archderm.1964.01600020021003

Bithionol is a primary photosensitizer.

Cross-reactions occurred with tetrachlorosalicylanilide (TCSA), tribromosalicylanilide (TBS), and hexachlorophene but not with trichlorocarbanilide (TCC).

Photopatch tests produced relatively characteristic responses for each substance.

Reactions to TBS and TCSA in patients with contact photodermatitis from bithionol represent true photo-cross-sensitivity.

Reactions to hexachlorophene in these patients with contact photodermatitis from bithionol did not require light. These reactions represent the unusual phenomenon of crosssensitivity between a photosensitizer and a simple contact allergen.

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