Benzonatate

Mechanism action of Benzonatate

Benzonatate acts peripherally, anesthetizing the stretch receptors of vagal afferent fibers in the alveoli of the lungs, bronchi, and pleura. Since these receptors are responsible for mediating the cough reflex, anesthetizing these receptors result in the inhibiton of cough production. Benzonatate also suppresses transmission of the cough reflex at the level of the medulla where the afferent impulse is transmitted to the motor nerves. When applied locally, Benzonatate binds within the intracellular portion of voltage-gated sodium channels, decreasing the rate of membrane depolarization and increasing the threshold for electrical excitability.