VA Class:RE302
ATC Class:R05DB01
Benzonatate is a local anesthetic antitussive agent.
Benzonatate is used for symptomatic relief of cough.100, 101, 106, 108 Benzonatate may be effective in suppressing cough in acute respiratory conditions such as pneumonia, bronchitis, pertussis, and the common cold; and in chronic diseases such as pulmonary emphysema, bronchial asthma, tuberculosis, and pulmonary tumor. Benzonatate has been shown to be more effective than codeine in reducing the frequency of experimentally induced cough,101 and may be effective in providing symptomatic relief in patients with opiate-resistant cough.108 Because of the drug's rapid, pronounced local anesthetic effect,100, 101, 102, 104, 107 benzonatate has been applied locally in the oral cavity in adults by releasing the drug from the liquid-filled capsules (e.g., by chewing or dissolving two 100-mg liquid-filled capsules in the mouth) to provide sufficient oropharyngeal anesthesia for conscious intubation†.107 This method of administration† must not be employed when the drug is used as an antitussive because of the risk of potentially life-threatening complications resulting from local effects of the drug on the oropharyngeal tract.100, 101, 102, 104 (See Cautions: Precautions and Contraindications and also see Dosage and Administration: Administration.)
Benzonatate is administered orally.100 Benzonatate liquid-filled capsules should be swallowed whole without chewing or dissolving in the mouth, since temporary local anesthesia of the oral mucosa, choking, or severe hypersensitivity reactions could occur; oropharyngeal anesthesia develops rapidly with such improper administration.100, 101, 102 However, such local administration has been employed to facilitate conscious intubation†.103, 107 (See Uses.)
The usual dosage of benzonatate for adults and children older than 10 years of age is 100 or 200 mg 3 times daily.100, 101, 106 If necessary, doses up to 600 mg daily may be given in divided doses.100, 101, 106 Children 10 years of age or younger have been given 8 mg/kg daily in 3-6 divided doses†, 106 although safety and efficacy have not been established in this age group.100 (See Cautions: Pediatric Precautions.)
Benzonatate generally is well tolerated when the liquid-filled capsules are swallowed intact.100, 101, 106 Adverse effects of benzonatate may include sedation, headache, mild dizziness, bizarre behavior (e.g., mental confusion, visual hallucinations), nasal congestion, nausea, GI upset, constipation, sensation of burning in the eyes, a vague “chilly” sensation, pruritus and skin eruptions, numbness in the chest, and hypersensitivity (e.g., bronchospasm, laryngospasm, cardiovascular collapse, possibly related to local anesthesia from chewing or sucking the liquid-filled capsules).100, 103, 106
Deliberate or accidental overdosage of benzonatate can result in CNS stimulation which may lead to restlessness, tremors, and seizures; profound CNS depression and death can follow.100, 103, 104, 105 (See Cautions: Pediatric Precautions.) Dizziness,104 disorientation,103 drunken feeling,104 unresponsiveness,104 pulmonary congestion,104 ventricular tachycardia,103 cardiac arrest,103 and nausea104 also have been reported with overdosage.
Acute benzonatate overdosage should be managed by evacuating the GI contents and administration of activated charcoal.100, 103 Protection against aspiration of gastric contents and orally administered substances should be ensured even in conscious patients because cough and gag reflexes may be substantially depressed.100 Seizures can be managed with a short-acting barbiturate, and intensive measures should be undertaken to maintain respiration and cardiovascular and renal function.100, 103, 104, 105 CNS stimulants should not be used.100
Precautions and Contraindications
Severe hypersensitivity reactions, including bronchospasm, laryngospasm, and cardiovascular collapse, have been reported with benzonatate.100, 101, 102 Such reactions may have resulted from local anesthesia secondary to sucking or chewing the liquid-filled capsules rather than swallowing them whole.100, 101 Severe reactions have required medical intervention with vasopressor therapy and supportive measures.100
Bizarre behavior, including mental confusion and visual hallucinations, has been reported rarely in patients receiving benzonatate concomitantly with certain other drugs.100
The possibility that adverse CNS effects associated with other p -aminobenzoic acid-derivative local anesthetics (e.g., procaine, tetracaine) could occur with benzonatate should be considered.100
Benzonatate is contraindicated in patients with known hypersensitivity to the drug or related compounds.100
Safe use of benzonatate during pregnancy or lactation has not been established.100
The safety and effectiveness of benzonatate in children under 10 years of age have not been established.111
The US FDA has warned the public that accidental ingestion of benzonatate (e.g., Tessalon) by children under the age of 10 years can result in death from overdose.111 Overdose with benzonatate in children less than 2 years of age has been reported following accidental ingestion of as few as 1 or 2 capsules.111 Benzonatate may be attractive to children because of the drug's appearance (it is a round-shaped liquid-filled gelatin capsule).111
Individuals who experience overdose of benzonatate may exhibit restlessness, tremors, convulsions, coma, and cardiac arrest.111 Signs and symptoms of overdose can occur rapidly after ingestion (within 15-20 minutes).111 (See Cautions: Adverse Effects.) Deaths in children have been reported within hours of the accidental ingestion.111
Patients who are taking benzonatate should keep the medication in a child-resistant container and store it out of reach of children.111 If a child accidentally ingests benzonatate, caregivers should immediately seek medical attention.111
Benzonatate apparently inhibits cough production by anesthetizing stretch receptors of vagal afferent fibers in the bronchi, alveoli, and pleura that mediate the cough reflex; the drug also suppresses transmission of the cough reflex at the level of the medulla where the afferent impulse is transmitted to the motor nerves. The relationship between local anesthetic action and peripheral action on sensory nerve endings is not clear. Benzonatate does not depress respiration at recommended dosages.100, 104, 106 In patients with bronchial asthma, the drug has been reported to increase the rate and depth of respiration, minute volume, and vital capacity.
Benzonatate usually acts within 15-20 minutes after oral administration.100, 103, 104, 106 The duration of action following a single oral dose is approximately 3-8 hours.100, 101, 103, 104, 106 Oropharyngeal anesthesia develops rapidly when the drug is applied locally (e.g., by chewing or dissolving the liquid-filled capsules in the mouth),100, 101, 102, 104, 107 with complete anesthesia occurring within about 1 minute.107
Benzonatate is an antitussive agent. The drug is chemically related to tetracaine and exhibits a local anesthetic action on mucosa following topical application. Benzonatate occurs as a clear, pale yellow, viscous liquid having a faint, characteristic odor. The drug is miscible in water in all proportions and is freely soluble in alcohol. The commercially available liquid-filled, soft-gelatin capsules contain benzoate in a vehicle of glycerin.100
Commercially available benzonatate liquid-filled capsules should be stored in tight, light-resistant containers at a controlled room temperature of 15-30°C.100
Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.
Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.
Routes | Dosage Forms | Strengths | Brand Names | Manufacturer |
|---|---|---|---|---|
Oral | Capsules, liquid-filled | 100 mg* | Tessalon® Perles | |
200 mg | Tessalon® Capsules | Forest |
* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name
100. Forest Pharmaceuticals. Tessalon® (benzonatate) prescribing information (dated 1999 Aug). In: Physicians' desk reference. 55th ed. Montvale, NJ: Medical Economics Company Inc; 2001:1270.
101. Food and Drug Administration. Cold, cough, allergy, bronchodilator, and antiasthmatic drug products for over-the-counter human use; tentative final monograph for OTC antitussive drug products. Proposed rule. [21 CFR Part 341] Fed Regist . 1983; 48:48576-95. (lDIS 176844)
102. Food and Drug Administration. Cold, cough, allergy, bronchodilator, and antiasthmatic drug products for over-the-counter human use; tentative final monograph for OTC antitussive drug products. Final rule. [21 CFR Part 310,341,369] Fed Regist . 1987; 52:30042-7. (lDIS 232963)
103. Crouch BI, Knick KA, Crouch DJ et al. Benzonatate overdose associated with seizures and arrhythmias. J Toxicol Clin Toxicol . 1998; 36:713-8. [PubMed 9865240]
104. Cohan JA, Conradi SE. Two fatalities resulting from Tessalon® (benzonatate). Vet Human Toxicol . 1986; 28:543-4.
105. Sheen S, Osterhoudt K, Birenbaum D. Seizures in a toddler associated with benzonatate ingestion. J Toxicol Clin Toxicol . 1997; 35:493.
106. Anon. Benzonatate. In: Osol A, Pratt R, eds. The United States dispensatory. Philadelphia: JB Lippincott Company; 1973:187-8.
107. Mongan PD, Culling RD. Rapid oral anesthesia for awake intubation. J Clin Anesth . 1992; 4:101-5. [PubMed 1562332]
108. Doona M, Walsh D. Benzonatate for opioid-resistant cough in advanced cancer. Palliat Med . 1998; 12:55-8. [PubMed 9616460]
109. Srinivasan A, Budnitz D, Shehab N et al. Infant deaths associated with cough and cold medications—two states, 2005. MMWR Morb Mortal Wkly Rep . 2007; 56:1-4. [PubMed 17218934]
110. Food and Drug Administration. Cough and cold medications in children less than two years of age. Rockville, MD; 2007 Jan 12. From FDA website. [Web]
111. Food and Drug Administration. FDA Alert: Tessalon (benzonatate): Drug Safety Communication - Potential for Accidental Ingestion by Children. Silver Spring, MD; 2010 Dec 14. From the FDA website. [Web]