MECHANISM OF ALLERGIC CONTACT-DERMATITIS FROM PROPACETAMOL - SENSITIZATION TO ACTIVATED N,N-DIETHYLGLYCINE

In order to confirm the mechanism of skin sensitization to propacetamo l, a pro-drug of acetaminophen, 3 patients with allergic contact derma titis from propacetamol were patch tested with N,N-diethylglycine phen yl ester, an activated form of N,N-diethylglycine. Positive patch test s were observed in all the patients at 10% in pet., while 20 control p atients remained negative. This strongly suggests that propacetamol is acting as an activated form of N,N-diethylglycine, transferring this part of the molecule to nucleophilic residues of proteins. This also e xplains why reactions to acetaminophen have never been observed in pat ients sensitized to propacetamol. (C) Munksgaard, 1998.