Abstract
The safety of oral clonidine substitution in 29 patients with confirmed localized allergic contact dermatitis due to transdermal clonidine treatment was evaluated. Only 1 patient had a skin reaction to oral clonidine. The dose of topical clonidine‐inducing sensitization, and the oral challenge dose administered later, appear to be insufficient to elicit a systemic reaction in most patients. An examination of current patch test technology seems indicated in view of the fact that a number of patients who gave a negative reaction to 48‐h applications of 9% clonidine in petrolatum responded positively to 7‐day application of transdermal clonidine.