Rodenticide Toxicity Clinical Presentation

Updated: Mar 16, 2023
  • Author: Derrick Lung, MD, MPH, FACEP, FACMT; Chief Editor: Asim Tarabar, MD  more...
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Many of the patients presenting with rodenticide ingestions are children who ingest such substances unintentionally and, thus, usually ingest small quantities. The literature relating to such ingestions is prone to the bias that ingestion may not have actually occurred or that it has occurred at such a low dose as to be inconsequential. Thus, determining the treatment of a child on the basis of published literature is potentially dangerous.

Adults who ingest such substances are most likely attempting suicide; however, homicidal poisoning may occur with these agents because of their ready availability. Surreptitious poisoning may occur from exposure to adulterated or contaminated drugs of abuse. The presence of anticoagulation may represent Munchausen syndrome.

Common presenting symptoms after exposure to long-acting anticoagulants include the following:

  • Flank pain with or without frank hematuria
  • Excess bleeding or bruising after relatively minor or no apparent trauma
  • Hemoptysis
  • Epistaxis
  • Menorrhagia

An organophosphate rodenticide known as TresPasitos, made with the chemical aldicarb and sold illegally in the United States, has been used primarily by Hispanic individuals. [14] People who ingest this toxin may present with symptoms of acetylcholinesterase inhibition.

Additional presentations of rodenticide exposure include the following:

  • Barium - May cause headache, weakness, nausea, abdominal pain, or shortness of breath
  • Bromethalin - Symptoms may include nausea, vomiting diarrhea, headache, agitation, drowsiness, dyspnea, choking, fever, loss of appetite and ocular irritation [5]
  • PNU - May cause complaints of nausea, vomiting, abdominal pain, or dizziness
  • Thallium - Exposed individuals may report acute GI distress and subsequent anorexia, myalgias, painful neuropathy, and hair loss
  • Strychnine - May cause anxiety, muscle twitching, or uncontrolled facial grimacing
  • Zinc phosphide - Inhalation leads to marked shortness of breath as pulmonary edema develops
  • Arsenic - High doses cause nausea, vomiting, bloody diarrhea, and garlic taste in the mouth

Verifying the specific rodenticide is important. In the United States, the rodenticide is most likely an anticoagulant. Quite a few of the other rodenticides have been used over the years but are currently not popular.


Physical Examination

Anticoagulant rodenticides rarely produce symptoms at all; when they do, however, symptoms are usually delayed. Evidence of frank bleeding, bruising, or other coagulopathy may be present if a significant exposure has occurred. The presence of petechiae under a blood pressure cuff may alert the nursing staff or ED physician to such coagulopathy.

Characteristic odors are associated with certain rodenticides.

  • PNU - Odor of peanuts
  • Zinc phosphide - Smells of rotting fish
  • Organophosphates, such as Tres Pasitos - Smell like garlic