[Topical anesthesia of the tympanic membrane using DMSO and local anesthetics].

A solution of 10% cocaine hydrochloride plus 10% water in 80% dimethyl sulfoxide (DMSO) or 5% tetracaine base in pure DMSO was topically applied to the eardrum in 112 and 52 cases respectively. Both preparations induced well-tolerated analgesia suitable for myringotomy with or without insertion of a grommet in the office environment. DMSO-tetracaine induced analgesia within ten, DMSO-cocaine within 30 minutes. This method has distinct advantages as compared to iontophoretically induced analgesia or topical agents with a destructive mode of action.