Tessalon Pearls Active Ingredient
The active ingredient in Tessalon pearls is benzonatate, a non-narcotic oral antitussive agent with the chemical name 2,5,8,11,14,17,20,23,26-nonaoxaoctacosan-28-yl p(butylamino) benzoate, with each capsule containing 200 mg of benzonatate USP. 1
Chemical Structure and Formulation
- Benzonatate is structurally related to local anesthetics such as tetracaine and procaine, functioning as a polyethoxy ester of 4-(butylamino) benzoic acid 2, 3
- The molecular weight is 603.7, and the compound exists as a mixture of polyethoxy esters with varying degrees of hydrophobicity 1, 3
- Each soft gelatin capsule contains inactive ingredients including D&C Yellow No. 10, gelatin, glycerin, and purified water 1
Mechanism of Action
- Benzonatate works as a peripherally acting antitussive by anesthetizing stretch receptors in the lungs, thereby reducing the cough reflex 4
- The drug inhibits voltage-gated sodium channels (including Nav1.7) in vagal sensory nerve fibers that mediate cough, similar to local anesthetic effects 3
- Detectable sodium channel inhibition occurs at concentrations as low as 0.3 μM, which has been documented in human therapeutic use 3
Clinical Dosing
- The recommended dosage for cough suppression is 100-200 mg three to four times daily according to American College of Chest Physicians guidelines 4
- Treatment should be limited to short-term symptomatic relief, typically 7-10 days for acute cough 4
Critical Safety Considerations
- Benzonatate overdose can cause rapid onset of life-threatening toxicity including seizures, cardiac arrest, dysrhythmias, and death within 15 minutes of ingestion 5, 6
- Fatal outcomes have been documented in children as young as 2 years old from accidental ingestion, with 20 of 31 reported overdose cases resulting in death 5, 7
- The medication is safe in patients with porphyria, with no evidence suggesting it triggers acute porphyria attacks 4