Sensitization to Monoglyceryl Para-aminobenzoate Preliminary Report

During recent years monoglyceryl para-aminobenzoate has been used as a chemical "filter" in sunburn preventives, including a few widely sold proprietary preparations. Monoglyceryl para-aminobenzoate has the advantages of a high capacity for filtering out the erythemaproducing portion of the sunlight spectrum, lack of odor, lack of staining properties and high stability under protracted exposure to sun irradiation (1). We have recently observed a male patient, age 48, who developed two attacks of allergic eczematous contact-type dermatitis due to monoglyceryl para-aminobenzoate in a proprietary sunburn preventive, as proven by a very strong eczematous patch test reaction to this compound and negative reactions to the other ingredients of the sunburn preventive. This patient previously had shown evidence of strong eczematous sensitization to benzocaine and to a sulfonamide (probably sulfaguanidine). Further patch tests in this patient showed that he was hypersensitive to unsubstituted para-aminobenzoic acid, aniline, parRphenylenediamine, procaine, sulfaguanidine and a number of other related compounds. The details of the immunochemical aspects of the sensitization in this case will be published in a later report.