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Toxicity, Shellfish: Treatment & Medication

Author: Thomas Arnold, MD, Medical Director, Louisiana Poison Control Center, Associate Professor and Chairman, Department of Emergency Medicine, Section of Clinical Toxicology, Louisiana State University Health Sciences Center
Contributor Information and Disclosures

Updated: Oct 29, 2009

Treatment

Prehospital Care

Support and maintenance of the airway are of crucial importance in PSP.

Emergency Department Care

  • Therapy for all shellfish poisonings is supportive and symptom-driven.
  • Gastrointestinal decontamination with activated charcoal is recommended for patients who present within 4 hours of ingestion. Nasogastric or orogastric lavage may be performed if the patient presents within 1 hour of ingestion, but this is often unnecessary.
  • If gastric lavage is performed, the use of isotonic sodium bicarbonate solution as a lavage irrigant has been suggested because many of the shellfish toxins have reduced potency in an alkaline environment.
  • Okadaic acid undergoes enterohepatic recycling that could be interrupted by delayed or repeat charcoal administration.
  • The greatest danger is respiratory paralysis. Close monitoring for at least 24 hours and aggressive airway management at any sign of respiratory compromise should prevent severe morbidity and mortality.
  • Neostigmine and edrophonium have been used to improve muscle weakness following tetrodotoxin intoxication, which is similar to saxitoxin intoxication. Nonetheless, no clinical trials have evaluated the use of these drugs for saxitoxin exposures.

Medication

Care is primarily symptomatic and supportive.

GI decontaminant

GI decontaminants are empirically used to minimize systemic absorption of the toxin. They may only be beneficial if administered within 1-2 h of ingestion.


Activated charcoal (Liqui-Char)

Emergency treatment in poisoning. Network of pores present in activated charcoal adsorbs 100-1000 mg of drug per gram of charcoal. Does not dissolve in water. For maximum effect, administer within 30 min of ingesting poison.
Cathartic not to be used in children <2 y.

Adult

1 g/kg (50-100 g) PO, with or without cathartic (eg, sorbitol)

Pediatric

1 g/kg (15-30 g) PO
<2 years: Cathartic not recommended

May inactivate ipecac syrup if used concomitantly; effectiveness of other medications decreases with coadministration; do not mix with sherbet, milk, or ice cream (decreases adsorptive properties)

Documented hypersensitivity; poisoning or overdose of mineral acids and alkalies; unprotected airway with absent gag reflex

Pregnancy

C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus

Precautions

Not very effective in poisonings of ethanol, methanol, and iron salts; induce emesis before administration; after emesis with ipecac syrup, patient may not tolerate activated charcoal for 1-2 h; can administer in early stages of gastric lavage; without sorbitol, gastric lavage returns are black; protect airway; monitor for bowel sounds before readministration to minimize risk of charcoal ileus

More on Toxicity, Shellfish

Overview: Toxicity, Shellfish
Differential Diagnoses & Workup: Toxicity, Shellfish
Treatment & Medication: Toxicity, Shellfish
Follow-up: Toxicity, Shellfish
References
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References

  1. Burgess V, Shaw G. Pectenotoxins--an issue for public health: a review of their comparative toxicology and metabolism. Environ Int. Oct 2001;27(4):275-83. [Medline].

  2. Lefebvre KA, Robertson A. Domoic acid and human exposure risks: A review. Toxicon. Jun 6 2009;[Medline].

  3. Centers for Disease Control and Prevention. Update: Neurologic illness associated with eating Florida pufferfish, 2002. MMWR Morb Mortal Wkly Rep. May 17 2002;51(19):414-6. [Medline].

  4. Bronstein AC, Spyker DA, Cantilena LR Jr, Green JL, Rumack BH, Heard SE. 2007 Annual Report of the American Association of Poison Control Centers' National Poison Data System (NPDS): 25th Annual Report. Clin Toxicol (Phila). Dec 2008;46(10):927-1057. [Medline]. [Full Text].

  5. Johnson RC, Zhou Y, Statler K, Thomas J, Cox F, Hall S, et al. Quantification of saxitoxin and neosaxitoxin in human urine utilizing isotope dilution tandem mass spectrometry. J Anal Toxicol. Jan-Feb 2009;33(1):8-14. [Medline].

  6. Nicholson BC, Shaw GR, Morrall J, Senogles PJ, Woods TA, Papageorgiou J, et al. Chlorination for degrading saxitoxins (paralytic shellfish poisons) in water. Environ Technol. Nov 2003;24(11):1341-8. [Medline].

  7. Ahmed FE. Seafood safety. Committee on Evaluation of the Safety of Fishery Products. Food & Nutrition Board, Institute of Medicine. National Academy Press; 1991.

  8. Chandrasekaran A, Ponnambalam G, Kaur C. Domoic acid-induced neurotoxicity in the hippocampus of adult rats. Neurotox Res. 2004;6(2):105-17. [Medline].

  9. Economou V, Papadopoulou C, Brett M, Kansouzidou A, Charalabopoulos K, Filioussis G, et al. Diarrheic shellfish poisoning due to toxic mussel consumption: the first recorded outbreak in Greece. Food Addit Contam. Mar 2007;24(3):297-305. [Medline].

  10. Gessner BD, Middaugh JP, Doucette GJ. Paralytic shellfish poisoning in Kodiak, Alaska. West J Med. Nov 1997;167(5):351-3. [Medline].

  11. Jeffery B, Barlow T, Moizer K, Paul S, Boyle C. Amnesic shellfish poison. Food Chem Toxicol. Apr 2004;42(4):545-57. [Medline].

  12. Kawatsu K, Hamano Y, Noguchi T. Production and characterization of a monoclonal antibody against domoic acid and its application to enzyme immunoassay. Toxicon. Nov 1999;37(11):1579-89. [Medline].

  13. Poli MA, Musser SM, Dickey RW, Eilers PP, Hall S. Neurotoxic shellfish poisoning and brevetoxin metabolites: a case study from Florida. Toxicon. Jul 2000;38(7):981-93. [Medline].

  14. Stommel EW, Watters MR. Marine Neurotoxins: Ingestible Toxins. Curr Treat Options Neurol. Mar 2004;6(2):105-114. [Medline].

  15. Usleber E, Dietrich R, Burk C, Schneider E, Martlbauer E. Immunoassay methods for paralytic shellfish poisoning toxins. J AOAC Int. Sep-Oct 2001;84(5):1649-56. [Medline].

  16. Vale P, Sampayo MA. Comparison between HPLC and a commercial immunoassay kit for detection of okadaic acid and esters in Portuguese bivalves. Toxicon. Nov 1999;37(11):1565-77. [Medline].

  17. Van Dolah FM. Marine algal toxins: origins, health effects, and their increased occurrence. Environ Health Perspect. Mar 2000;108 Suppl 1:133-41. [Medline].

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Further Reading

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Keywords

paralytic shellfish poisoning, PSP, neurologic shellfish poisoning, NSP, diarrheal shellfish poisoning, DSP, amnestic shellfish poisoning, ASP, brevetoxin, brevotoxin, shellfish toxicity, shellfish poisoning, shellfish exposure, shellfish ingestion, hepatitis A, Norwalk virus, Vibrio parahaemolyticus, Vibrio vulnificus, toxic shellfish, saxitoxin, okadaic acid, domoic acid

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Contributor Information and Disclosures

Author

Thomas Arnold, MD, Medical Director, Louisiana Poison Control Center, Associate Professor and Chairman, Department of Emergency Medicine, Section of Clinical Toxicology, Louisiana State University Health Sciences Center
Thomas Arnold, MD is a member of the following medical societies: American Academy of Emergency Medicine, American College of Emergency Physicians, American College of Medical Toxicology, Louisiana State Medical Society, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Medical Editor

Robert L Norris, MD, Associate Professor, Department of Surgery; Chief, Division of Emergency Medicine, Stanford University Medical Center
Robert L Norris, MD is a member of the following medical societies: American College of Emergency Physicians, American Medical Association, California Medical Association, International Society of Toxinology, Society for Academic Emergency Medicine, and Wilderness Medical Society
Disclosure: Nothing to disclose.

Pharmacy Editor

John T VanDeVoort, PharmD, Regional Director of Pharmacy, Sacred Heart & St. Joseph's Hospitals
John T VanDeVoort, PharmD is a member of the following medical societies: American Society of Health-System Pharmacists
Disclosure: Nothing to disclose.

Managing Editor

Michael J Burns, MD, Instructor, Department of Emergency Medicine, Harvard University Medical School, Beth Israel Deaconess Medical Center
Michael J Burns, MD is a member of the following medical societies: American Academy of Clinical Toxicology, American College of Emergency Physicians, American College of Medical Toxicology, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

CME Editor

John D Halamka, MD, MS, Associate Professor of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center; Chief Information Officer, CareGroup Healthcare System and Harvard Medical School; Attending Physician, Division of Emergency Medicine, Beth Israel Deaconess Medical Center
John D Halamka, MD, MS is a member of the following medical societies: American College of Emergency Physicians, American Medical Informatics Association, Phi Beta Kappa, and Society for Academic Emergency Medicine
Disclosure: Nothing to disclose.

Chief Editor

Asim Tarabar, MD, Assistant Professor, Director, Medical Toxicology, Department of Emergency Medicine, Yale University School of Medicine; Consulting Staff, Department of Emergency Medicine, Yale-New Haven Hospital
Disclosure: Nothing to disclose.

 
 
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