Abstract
Little has been published on benzonatate ingestion, with the few case reports suggesting significant risk of seizures after poisoning. A 7-year retrospective review of all single substance ingestion of benzonatate reported to the National Poison Center Database System (NPDS) from 2000 to 2006. In this review, there were 2,172 patients, of which 1,280 (58%) were female. Mean age was 20 years, with 676 (30%) <6 years. Serious outcomes occurred in 116 (moderate, n = 81, 4%; major, n = 31, 1%; and death, n = 4, 0.2%). Mean age of those with serious outcome was 21 years, with 41 (35%) in children less than 6 years old. Forty-nine percent (1,084) patients were treated in a healthcare facility (HCF) of which 148 (7%) were admitted for medical care. Clinically significant effects that were documented included tachycardia (n = 31, 1%), agitation (n = 30, 1%), seizure (n = 23, 1%), coma (n = 14, 0.6%), ventricular dysrhythmia (n = 9, 0.4%), cardiac arrest (n = 8, 0.3%), hypotension (n = 7, 0.3%), and asystole (n = 6, 0.2%). Of patients with seizures reported, eight patients (0.4%) had multiple/discrete seizures and two had status epilepticus documented. Dysrhythmias but not seizures occurred in all fatalities in this review. Significant CNS and cardiac effects occurred in a small subset of this study (<1%), while half the patients received direct medical care in an HCF. No correlation between age and severity of medical outcome was detected by statistical analysis. A prospective study to better evaluate potential HCF triage criteria such as dosage, age, or preexisting conditions may be warranted. The fatalities from this study were due to dysrhythmias rather than seizures as previously reported in previous case reports. There were no clinical correlations between severity of outcomes and dose ingested. A median dose of 200 mg or greater suggests a potential for producing serious outcomes in a benzonatate exposure.
Keywords: Benzonatate, Poisoning, Dysrhythmia, National database
Full Text
The Full Text of this article is available as a PDF (111.8 KB).
Declaration of Interest
The authors report no conflict of interest. The authors alone are responsible for the content and writing of the manuscript.
Footnotes
Part of this work was presented as a poster at the 2008 North American Congress of Clinical Toxicology, Toronto, Canada, on September 14, 2008.
References
- 1.Product Information. Tessalon (benzonatate). St. Louis, MO: Forest Pharmaceuticals, July 2007.
- 2.Estfan B, LeGrand S. Management of cough in advanced cancer. J Supp Oncol. 2004;2:523–527. [PubMed] [Google Scholar]
- 3.Homsi J, Walsh D, Nelson KA. Important drugs for cough in advanced cancer. Support Care Cancer. 2001;9:565–574. doi: 10.1007/s005200100252. [DOI] [PubMed] [Google Scholar]
- 4.Doona M, Walsh D. Benzonatate for opioid-resistant cough in advanced cancer. Palliat Med. 1998;12:55–58. doi: 10.1191/026921698672930910. [DOI] [PubMed] [Google Scholar]
- 5.Cohan JA, Manning TJ, Lukash L, et al. Two fatalities resulting from Tessalon™ (Benzonatate) Vet Hum Toxicol. 1986;28:543–544. [PubMed] [Google Scholar]
- 6.Crouch BI, Knick KA, Crouch DJ, et al. Benzonatate overdose associated with seizures and arrhythmias. J Toxicol Clin Toxicol. 1998;36:713–718. doi: 10.3109/15563659809162620. [DOI] [PubMed] [Google Scholar]
- 7.Sheen S, Osterhoudt K, Birenbaum D. Seizures in a toddler associated with benzonatate ingestion (abstract 31) J Toxicol Clin Toxicol. 1997;35:493. [Google Scholar]
- 8.Shropshire A, Clifton J, II, Aks S, et al. Death from intentional IV administration of benzonatate (abstract 169) J Toxicol Clin Toxicol. 1999;37:652. [Google Scholar]
- 9.Borys DJ, Morgan DL, Juan J, Vincent CB. Pediatric benzonatate exposures: a six-year retrospective review of 67 patients (abstract 297) J Toxicol Clin Toxicol. 2006;44:768–769. [Google Scholar]
- 10.Schwarz KA, Vohra R, Clark RF. Retrospective evaluation of outcomes of benzonatate exposures: a statewide poison control system based study (abstract 317) J Toxicol Clin Toxicol. 2006;44:777. [Google Scholar]
- 11.Bronstein AC, Spyker DA, Cantilena LR, et al. 2007 Annual Report of the American Association of Poison Control Centers’ National Poison Data System (NPDS): 25th Annual Report. Clin Toxicol. 2008;46:927–1057. doi: 10.1080/15563650802559632. [DOI] [PubMed] [Google Scholar]