Benzonatate

It is a local anesthetic anti-tussive drug.


Mechanism of Action:
It acts as cough depressant in two ways:
1. It anesthetizes the stretch receptors of vagal afferent fibers in bronchi, alveoli and pleura that are involved in cough reflex.
2. It depresses the cough reflex at the level of medulla at the point where afferent impulse is transmitted to the motor nerves.

Therapeutic Uses:
1. Cough:
It is used for the symptomatic treatment of cough. It can be effective in reducing cough in conditions like pneumonia, common cold, bronchial asthma and tuberculosis.

2. As local anesthetic:
It is used in liquid filled capsules (Which are chewed), as local anesthetic of oropharyngeal cavity for attentive intubation.

Administration and dosage:
It is given orally. And its dose for adults and children older than 10 years of age is 100 to 200 mg 3 times daily.

Pharmacokinetics:
1. Its onset of action is 15-25 minutes.
2. Its duration of action is 2.5-8 hours.
3. Anesthesia of oropharyngeal cavity occurs within 1 minute.

Adevrse Effects:
Sedation, Headache, Nausea, Pruritis and skin eruptions, Hypersensitivity and nasal congestion.