Allergic contact dermatitis due to a Chinese orthopaedic solution tieh ta yao gin

3 cases of contact dermatitis due to a Chinese herbal orthopaedic solution Tieh Ta Yao Gin and its putative ingredients are reported. Patch testing demonstrated allergy to mastic and myrrh, natural gum resins widely used in traditional Chinese medicine to relieve pain and swelling due to traumatic injury.