|Trade names||Tessalon, Tessalon Perles|
|Elimination half-life||3-8 hours|
|Chemical and physical data|
|Molar mass||603.742 g/mol|
|3D model (JSmol)|
|(what is this?)|
Benzonatate—marketed under the trade names Tessalon, Tessalon Perles, and Zonatuss—is a non-narcotic oral cough suppressant, or antitussive, with effects that last from six to eight hours. Since it is not an opioid, benzonatate has no abuse liability, in contrast to some other cough medications such as codeine. Benzonatate was approved by the U.S. Food and Drug Administration (FDA) in 1958.
Pharmacologic mechanisms of action
An antitussive, benzonatate is employed to reduce coughing in various respiratory conditions such as bronchitis, emphysema, influenza, and pneumonia.
Dosage and administration
Benzonatate is sold as yellow or blue 100 mg and 200 mg softgel capsules. Initial dose is one 100 mg perle (gelcap) by mouth, 3 times a day. Dosage may be increased as necessary, up to a maximum of 600 mg per day.
Due to its potency and potential toxicity, the capsules must be swallowed intact in order to allow slower release of the medication.
Para-aminobenzoic acid (PABA) is a metabolite of the ester class of local anesthetics, which includes benzonatate, as well as procaine and tetracaine. Severe allergic reactions have been reported in patients who are allergic to PABA. Severe sensitivity reactions to benzonatate have resulted in respiratory side effects such as bronchospasm, laryngospasm, and cardiac arrest.
Excessive absorption of benzonatate (a local anesthetic) in the oral mucosa will result in the rapid development of numbness of the mouth and throat. In extreme cases, the mouth and pharynx may become so numb that pulmonary aspiration may occur.
Excessive absorption of benzonatate will occur if the gelcaps are chewed or allowed to dissolve in the mouth. This may lead to an overdose of the drug. Overdose of benzonatate may manifest as central nervous system side effects, such as mental confusion and hallucination, restlessness and tremors, followed in extreme cases by convulsions and death.
- MedicineNet.com: Benzonatate
- Medicalook.com: Benzonatate
- Medline Plus: Benzonatate
- Crouch, B. I.; Knick, K. A.; Crouch, D. J.; Matsumura, K. S.; Rollins, D. E. (1998). "Benzonatate overdose associated with seizures and arrhythmias". Journal of Toxicology. Clinical Toxicology. 36 (7): 713–718. doi:10.3109/15563659809162620. PMID 9865240.
- Cohan, J. A.; Manning, T. J.; Lukash, L.; Long, C.; Ziminski, K. R.; Conradi, S. E. (1986). "Two fatalities resulting from Tessalon (benzonatate)". Veterinary and human toxicology. 28 (6): 543–544. PMID 3788039.