There are various causes of contact dermatitis. The common agents in Japan include Asian poison ivy, disinfectant, ointment of various kinds, poultice, shampoo, rubber glove, hair dye, and mango. It can also be caused by metal allergy. 

The management of contact dermatitis is best achieved by avoiding the causative agent, however, the "agent" may remain unknown. Emollients protect the lesion while a short course of topical corticosteroid creams is generally used.  Oral antihistamine or a short course of oral prednisolone may be added depending upon the severity.