SUMMARY:A case of allergic contact dermatitis to cinchocaine is presented to highlight the confusion regarding the classification of, and cross‐reactivity between, topical anaesthetic agents and the inadequacy of the use of benzocaine as a single screening agent for topical anaesthetic contact allergy. Our patient presented with a 10‐day history of acute perianal dermatitis. Allergic contact dermatitis to Proctosedyl® ointment, which was applied for 3 weeks prior, was suspected. On patch testing, he reacted to cinchocaine, a constituent of Proctosedyl® ointment, and to the actual product, but had no reaction to benzocaine or lignocaine.