Toxicology

Toxicology Overview

Resources

  • Clinical Textbook for Veterinary Technicians

  • Poisonous Plants

  • Powerpoint on Bb Eve

  • Pages 824-840

History of Toxicology

Key Figure: Paracelsus (1493-1541)

  • Famous Quote: "All things are poison, and nothing is without poison; only the dose makes a thing not a poison."

  • Often paraphrased as: "The dose makes the poison."

Importance of History

  • Critical for assessing patient health during clinical visits or phone conversations.

  • Essential questions for history taking include:

    • Current clinical status of the animal.

    • Identification of the toxin and exposure route.

    • Amount of toxin the animal was exposed to.

    • Timing of the exposure.

    • Age and weight of the animal.

    • Sex of the animal; for females, inquiry about lactation or pregnancy.

    • Any previous health issues.

    • Medications the animal is currently taking.

    • Recent surgeries.

    • Owner’s actions taken for treatment.

    • Exposure of other animals.

Physical Examination

  • Initial assessment should focus on:

    • Consciousness and mental status.

    • Respiratory rate and heart rate.

    • Capillary refill time.

    • Mucous membrane color.

    • Body temperature.

  • Create a problem list based on findings.

Stabilization of Vital Functions

  • Address Airway, Breathing, Circulation (ABCs) before decontamination attempts.

  • Closely monitor cardiovascular system; IV catheter placement may be needed.

Decontamination Procedures

Ocular Exposure

  • Flush eyes with tepid water for a minimum of 20-30 minutes.

  • Examine eyes for corneal damage.

Dermal Exposure

  • Bathe animal using mild liquid dishwashing detergent.

  • Proper PPE must be worn.

  • Avoid sticky substances or mineral oil on birds.

  • Thoroughly dry the animal afterward.

Oral Ingestion

Dilution

  • Recommended with milk or water for corrosive or irritant ingestions.

Emesis

  • Induction can be performed in some toxin ingestion cases, considering:

    • Time since ingestion.

    • Contraindications include severe depression, comatose state, hydrocarbons, corrosive materials.

    • Hydrogen peroxide: 1 ml/lb, max 45 mls (not for cats).

    • Preferred emetic: Apomorphine hydrochloride for dogs; horses, rabbits, and rodents cannot vomit.

Activated Charcoal

  • Adsorbs toxins when given orally following ingestion.

  • Contraindicated after ingestion of caustic materials.

Cathartics

  • Used to enhance elimination of activated charcoal and adsorbed toxins.

  • Contraindications include diarrhea and dehydration.

Enemas

  • Useful in eliminating toxicants from the lower GI tract (plain or soapy water).

  • Not performed in birds.

Gastric Lavage

  • Requires general anesthesia; not for caustic/petroleum distillate ingestions.

  • Enterogastric lavage involves rectal lavage to clear large fecal matter.

Supportive Care

  • Regular monitoring of vital signs.

  • Blood work (CBC, chem panels, coagulation profiles).

  • Supportive care until recovery.

Household Hazards

Dangerous Food Items

  • Moldy Food: Tremorgenic mycotoxins may cause seizures.

  • Chocolate: Contains theobromine and caffeine; early treatment critical.

  • Macadamia Nuts: Neurological symptoms in dogs.

  • Yeast Dough: Life-threatening to dogs; administer cold water/ice cubes.

  • Grapes/Raisins: Can cause kidney failure in some dogs.

  • Onions: Hemolytic anemia; decontamination is necessary.

  • Xylitol: Severe hypoglycemia; treatment includes emesis and IV dextrose.

Household Cleaning Agents

  • Acids: Found in cleaners; can cause severe gastric issues.

  • Alkalis: Cause burns; effects may be delayed.

  • Bleaches and Detergents: Require specific treatment protocols.

Miscellaneous Household Hazards

  • Zinc: Found in hardware; removal via endoscopy is needed.

  • Lead: Affects multiple body systems; removal methods vary.

  • Nicotine: Found in tobacco; leads to respiratory paralysis.

Pesticides

  • Ant and Roach Baits: Can cause foreign body issues; dogs sensitive to bifenthrin.

  • Flea/Tick Products: Risk to felines.

  • Rodenticides: Several types require immediate stabilization and treatment.

Antifreeze Products

  • Ethylene Glycol: Highly dangerous; leads to renal failure.

  • Methanol: Sedation and ataxia upon larger exposure.

  • Propylene Glycol: Safer but can cause CNS issues in significant amounts.

Human Medications

Common Dangerous Drugs

  • Acetaminophen: Especially toxic to cats; causes liver damage.

  • NSAIDs: More toxic to cats; can cause severe issues with dosage not managed.

  • Aspirin: Must use cautiously in cats; certain dosage can be fatal.

Other Medications

  • Pseudoephedrine and Amphetamines: Risk of CNS issues and tachycardia.

  • 5-Fluorouracil: Causes severe neurological effects in dogs.

Drugs of Abuse

  • Marijuana and Cocaine: Can lead to severe toxicological signs.

  • Ethanol: Symptoms vary in severity; requires supportive care.