Compound allergy to an antihemorrhoidal ointment demonstrated by the repeated open application test.

The most commonly used topical pharmacologic agents for symptomatic management of hemorrhoids include vasoconstrictors, astringents, anesthetics, keratolytics, corticosteroids, and antipruritic agents. Some of these drugs have been involved in contact dermatitis [1-7]. A 57-year-old woman presented with a pruritic, sharply demarcated, erythematous rash on the anogenital area that spread within 2-3 days to the trunk, neck, forearms, groins, and upper inner aspect of the thighs. The rash began 3 to 4 days after application of an antihemorrhoidal ointment (Ruscus Llorens, Llorens, Barcelona, Spain) containing ruscogenin, prednisolone, cinchocaine, menthol, zinc oxide, and excipients (a mixture of parabens [methyl, ethyl, and butyl], polyethylene glycol, and cetyl alcohol). Avoidance of the antihemorrhoidal ointment and treatment with topical and oral corticosteroids and oral antihistamines improved the lesions within 2 weeks. The patient denied previous exposure to the ointment and had no history of atopy or contact dermatitis. One month after the reaction, the patient tolerated varicose vein cream containing Ruscus aculeatus (its primary active ingredients are ruscogenins), Melilotus offi cinalis, zinc oxide, the paraben mixture (methyl, ethyl, and butyl), and sodium edetate. Six weeks later, we performed patch tests using the Spanish Contact Dermatitis Research Group standard series and corticosteroid series, the antihemorrhoidal ointment as is, and all the individual components to which the patient had not been exposed to after the reaction (ie, ruscogenin 30% pet and 30% eth, prednisolone 1% pet, cinchocaine 5% pet, menthol 2% pet, polyethylene glycol 4% pet, and cetyl alcohol 5% pet). These concentrations were higher than in the ointment. Readings at 48 hours, 96 hours, and 1 week were negative for all of them. A repeated open application test (ROAT) was performed on the flexor forearm with the ointment as is and its individual components (2 daily applications for 7 days). Negative results were obtained with the individual components, but the result for the ointment was positive on the third day: erythema, papules, infi ltration, and pruritus appeared on the application area, although they all resolved within 7 days (Figure). The results of the same test performed on 5 control patients proved negative.