ABVT cheat sheet

Species-specific xenobiotic metabolism: cats lack glucuronidation capacity, so acetaminophen and permethrin exposures cause Heinz body anemia and tremors respectively.

Chocolate toxicosis: theobromine is the principal toxin; milk chocolate contains roughly 44 mg/g theobromine, unsweetened baking chocolate roughly 390-450 mg/g.

Grape/raisin ingestion in dogs causes acute renal failure of uncertain mechanism; no established toxic dose means any exposure warrants decontamination.

Ivermectin sensitivity: ABCB1 (MDR1) gene mutation in collies and related breeds causes neurotoxicity at doses tolerated by other dogs.

Vitamin D rodenticide (cholecalciferol) causes hypercalcemia and hyperphosphatemia; treat with bisphosphonates, calcitonin, or mifepristone and fluid diuresis.

Anticoagulant rodenticide toxicity is confirmed by prolonged prothrombin time (PT); treat with vitamin K1, not vitamin K3.

Onion and garlic cause oxidative hemolysis in dogs and cats; cats are more susceptible due to hemoglobin oxidation sensitivity.

Zinc phosphide rodenticide releases phosphine gas, which is also a hazard to the treating veterinarian; avoid inducing emesis.

LD50 is the dose causing death in 50% of exposed animals; lower LD50 means higher acute toxicity.

Therapeutic index = LD50/ED50; a narrow index means small dose changes produce toxicity.

Henderson-Hasselbalch: weak acids are un-ionized and better absorbed in acidic gastric pH; weak bases are absorbed in more alkaline environments.

Biotransformation phases: phase I (oxidation, reduction, hydrolysis via CYP450) often produces reactive intermediates; phase II (glucuronidation, sulfation, acetylation) increases water solubility for excretion.

Decontamination windows: emesis is generally useful only within 1-2 hours of ingestion; activated charcoal adsorbs many organic compounds but is contraindicated for hydrocarbons and caustics.

Volume of distribution (Vd) predicts dialyzability: low Vd compounds are more amenable to hemodialysis or hemoperfusion.

Toxicity is dose-dependent, and toxic effects may be local, systemic, or both; systemic effects require absorption into circulation.

Cholinergic toxidrome (SLUDGE: salivation, lacrimation, urination, defecation, GI distress, emesis) indicates organophosphate or carbamate exposure.