Allergic contact dermatitis from hearing aid materials.

A 65-year-old woman presented with dermatitis of the ear canal. The dermatitis had developed after she started wearing hearing aids that fit into the ear canals. Patch-test results were positive for (1) several acrylics, including polyethylene glycol dimethacrylate and 2-hydroxyethyl methacrylate, which were present in the hearing aid shell; (2) the hearing aid shell materials; and (3) the finish coat. The dermatitis resolved after she discontinued wearing the hearing aid, and a device with a silicone earpiece to be worn behind the ear was recommended as an alternative.