Drug-Induced Patency Changes in the Eustachian Tube: A Comparison of Routes of Administration

Abstract

This report is a survey of the patency responses of a dog's eustachian tube to some important pharmacologic agents. Drugs were introduced by three routes: intra-arterial, intravenous, and topical. The patency change of the eustachian tube to a particular drug was usually the same regardless of the route of administration. Patency changes could usually be elicited with drug doses given in the nanogram or microgram range. Large blood pressure changes altered the patency changes and, in some cases, reversed their direction. Of the 13 drugs tested, levarterenol and prostaglandin E₁ did not exhibit "typical" behavior. When these two drugs were given topically, the direction of the patency response depended on the dose.