Patent ID: 8192420

Claim:
A method of anesthetizing tympanic membranes in a patient, the patient having a first and a second ear canal, the method comprising: delivering an amount of an anesthetizing drug solution to the first ear canal, wherein the drug solution includes an anesthetic and a buffer, and wherein the drug solution has a pH in the range of about 6.5 to about 7.5; delivering an additional amount of the anesthetizing drug solution to the second ear canal; inserting a first electrode of an iontophoresis device in the first ear canal to contact the anesthetizing drug solution; inserting a second electrode of the iontophoresis device in the second ear canal to contact the anesthetizing drug solution; attaching a ground electrode of the iontophoresis device to the patient, the first electrode and the ground electrode forming a first circuit, the second electrode and the ground electrode forming a second circuit; energizing the first circuit to deliver a current to the anesthetizing drug solution in the first ear canal via the first electrode to cause at least some of the drug solution to pass into a first tympanic membrane; energizing the second circuit to deliver a current to the anesthetizing drug solution in the second ear canal via the second electrode to cause at least some of the drug solution to pass into a second tympanic membrane, independently of energizing the first circuit and while energizing the first circuit; independently increasing the current delivered to the first and second electrodes at a ramp-up rate of about 0.2 milliamp per second until a maximum delivered current is achieved in each electrode; and displaying a progress meter for each of a left and right ear indicating delivery of the current to the anesthetizing drug solution for each of the left and right ear.