Rodenticides And Other Large Animal Toxins

Strychnine/Brucine

  • Effects/MOA
    • Glycine receptor antagonist on spinal cord
    • PNS
  • Clinical Manifestations
    • Conscious seizures, until metabolic demands lead to AMS, multiorgan failure (renal, heart, brain, lung)
  • MGMT/Notes
    • Benzos, cooling, hydration, nondepolarizing NMB, urine alkalinization
    • AC binds 1:1 so 1g/kg x 1
    • Effective management within first 6 hours is essential
    • Rapid onset vs tetanus (which inhibits glycine release, not competitive antagonism)
    • Professor Touery survived strychnine by also ingesting AC
    • Mole/gopher poison
    • Adulterant in drugs (cocaine, heroin, meth, mdma)

Brodifacoum

  • Effects/MOA
    • Blood

Alpha-naphthylthiourea (ANTU)

  • Effects/MOA
    • “Organosulfur” Rat poison used in the 1940s in baltimore since rats don’t mind the taste
    • Shortness of breath, pulmonary toxicity, edema
  • Clinical Manifestations
    • LUNG
    • Pulmonary injury and pulmonary edema
  • Notes
    • Toxic products produced by lung NADPH dependent CYP enzymes

Barium carbonate

  • Effects/MOA
    • Depolarizing neuromuscular blockade
    • K shifted intracellularly producing profound weakness
  • Clinical Manifestations
    • FACIAL parasthesias are the first symptoms
      • Followed by descending paralysis and cardiac conduction
      • Potassium replacement aids in reversing paralysis
  • Notes
    • HD

Bromethalin

  • Effects/MOA
    • Uncouples oxidative phosphorylation AND interrupts nerve impulse conduction
    • CNS- seizures, ataxia confusion, tremors

Phosphides

  • Effects/MOA
    • Phosphine- cytochrome a or c oxidase inhibitor
    • Rotten fish ordor

N-3-pyridylmethyl-N-p- nitrophenylurea (PNU) aka Pyriminil

  • Effects/MOA
    • Structurally related to chemotherapeutics (alloxan, streptozocin) → destroying pancreatic beta cells
  • Clinical Manifestations
    • PANCREAS
    • Can have delayed onset of DAYS
    • New onset diabetes, DKA, hyperglycemia
    • Peanut odor

Tetramine

  • Effects/MOA
    • GABA antagonist
    • Refractory seizures

Sodium monofluoroacetate, Fluroacetamide

  • Effects/MOA
    • Metabolite, fluorocitrate, acts as a “suicide inhibitor” of ACONITASE producing a biochemical dead end.
    • Net increase in substrates proximal to aconitase in citric acid cycle and depletion of substrates distal to it.
    • ←—-xACONITASEx—->
  • MGMT
    • ETHANOL(?) target level of 100
  • Notes
    • Also causes alpha-ketoglutarate accumulation
    • Glutamate depletion and ammonia accumulation
    • Also impairs fatty acid oxidation leading to ketosis
    • HYPOCALCEMIA from excess citrate. Not due to fluoride, NO defluorination occurs
    • SMFA classified as a potential chemical weapon, like tetramine

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Rodenticides And Other Large Animal Toxins