Veterinary Toxicology Quiz

Fluoride Toxicity

• Fluoride is a mineral found in mineral beds, soil, and water.
• Livestock are commonly affected by fluoride overexposure.
• Overdosing on fluoride can cause two major problems:
  • Bone growth issues: spongy bone (leading to lameness, joint spurs).
  • Dental enamel issues: softened enamel in young animals.
• Diagnosis involves mineral/soil/water analysis or bone biopsy (coccygeal vertebra). Urine analysis from 1-3 weeks after exposure can also be used.
• Treatment may involve transferring to a veterinary hospital, adding aluminum or calcium carbonate to the diet, or a combination of these approaches.

Anticholinesterases

• Organophosphates (e.g., Sarin):
  • Stable in the body, requiring treatment to remove.
• Carbamates:
  • Unstable, easily metabolized, but fast-acting and lethal.
  • Used for pesticide control in some animals like cattle.
  • Illegal aldicarb is also present in some areas and can be almost instantly fatal to dogs.
• Anticholinesterase toxicity causes parasympathetic overdrive and neuromuscular issues.
• Signs include SLUD (salivation, lacrimation, urination, defecation) and muscular contractions progressing to paralysis.
• Some organophosphates can cause a delayed neuropathy.
• Clinical signs are cumulative, meaning the signs worsen over time.

Treatment for Anticholinesterases

• Quick treatment is crucial. High doses of activated charcoal.
• Administer atropine to aid in recovery.
• Use 2-PAM to promote the release of organophosphates from AChE.
• Be aware of anti-AChE toxins in milk.

Parasympathetic Overdrive

• Rapid progression of SLUD signs, dyspnea (with lung edema), and respiratory rales.
• Potential muscle tremors, seizures, and paralysis.
• Acute death due to loss of respiratory muscle function.
• Ruminants (slow digestion) will have a longer duration of illness.
• Dogs can develop acute necrotic hemorrhagic pancreatitis.

Pyrethrins and Pyrethroids

• Pyrethrins are naturally extracted from chrysanthemum plants.
• Pyrethroids are synthetic man-made chemicals.
• Cats are especially sensitive to pyrethrins and pyrethroids toxicity.
• The compounds are lipid-soluble and stored in body fat. This may cause delayed effects.
• Clinical signs include salivation (difficulty swallowing), hyperesthesia, twitching, ataxia, and abnormal behavior.
• Skin irritation is also a possible sign.

Treatment for Pyrethrins and Pyrethroids

• No specific antidote.
• Decontamination: clean the skin with mild dish soap and use activated charcoal.
• Manage seizures with appropriate medications (e.g., methocarbamol).
• Potential need for dextrose supplementation.

Anticoagulants (Rat Bait)

• First-generation anticoagulants (e.g., warfarin) are less potent and their effects last a few days.
• Second-generation anticoagulants (e.g., bromadialone, brodifacoum) are more common and potent; their effects last for 12-30 days.
• The mechanism of anticoagulants involves interfering with vitamin K-dependent enzymes involved in blood clotting.
• Affected animals commonly display varied bleeding tendencies, including anemia, melena, bloody vomit, diarrhea, epistaxis, hematomas, and bleeding into joints/feet that can cause lameness.
• Diagnostics typically involve measuring prothrombin time (PT) and partial thromboplastin time (PTT).

Treatment for Anticoagulants

• Decontamination, depending on timing (activated charcoal).
• Administration of vitamin K1 (2-5 mg/kg IM/SC/PO once daily).
• Treatment length will vary based on the generation of the anticoagulant. The duration is often one week for first generation and up to six weeks (or longer) for second generation. Follow-up coagulation checks are necessary to monitor effects.
• Blood transfusions may also be necessary to treat the anemia.
• Fresh frozen plasma should be the preferred solution to avoid risk of spreading non-anemic blood issues and to provide clotting factors.

Cholecalciferol (Vitamin D3) Toxicity

• Vitamin D3 overdose results in hypercalcemia and hyperphosphatemia.
• Clinical signs include depression, weakness, ataxia, vomiting, hematemesis, constipation, melena, polyuria/polydipsia (PU/PD), dehydration, bradycardia, and cardiac arrhythmias.
• Tissue mineralization is dependent on the area of tissue involvement and severity of the signs.
• Labs will show depressed parathyroid levels with hypercalcemia and calciuria.

Treatment for Vitamin D3 Toxicity

• Decontaminate the patient by inducing emesis and administering activated charcoal.
• Restrict the dietary calcium and phosphorus in the diet.
• Monitor blood calcium every 24 hours for 6 days.
• Use Prednisolone to limit the activation of vitamin D3, Furosemide for diuresis, and intravenous fluids.
• Pamidronate disodium (1.3-2mg/kg IV in 0.9%NaCl over 2-4 hours) can also be used.
• Repeat treatments after appropriate durations depending on the response of the treatment and the severity of the toxicity.

Strychnine Toxicity

• Strychnine is a highly potent poison frequently found in coyote bait, and it's relatively common in dogs.
• The toxin blocks glycine's effect on inhibitory GABA receptors and suppresses chloride conductance, escalating reflexes, muscle spasms, and convulsions.
• Initial symptoms include apprehension, anxiety, and salivation. This progresses to severe extensor rigidity and tonic convulsions.

Treatment for Strychnine Toxicity

• Decontamination through emesis, gastric lavage, activated charcoal, and cathartics.
• Controlling muscle spasms through medications such as diazepam or other barbiturates or methocarbamol.
• Supportive therapy with IV fluids, treat hyperthermia, and acidosis.
• Diagnosis commonly involves evaluating stomach contents for legal cases.

Zinc Phosphide Toxicity

• Zinc phosphide is a rodenticide used against moles, gophers, and rats.
• Exposure results in zinc phosphide reacting with stomach acid to release phosphine gas.
• Affected tissues include the heart, brain, liver, kidneys, and lungs.
• Clinical signs often include rapid onset of vomiting with blood, severe gastrointestinal upset and hemorrhage, followed by tremors, fasciculations, respiratory distress, convulsions, and shock. Death occurs within hours.
• Affected animals may also exhale phosphine gas ("garlicky" odor). Handlers are at risk of exposure and should consider good ventilation.

Treatment for Zinc Phosphide Toxicity

• Decontamination: induce vomiting (if applicable), use activated charcoal.
• Administer direct-acting antacids to limit phosphine release.
• Consider gastric lavage.
• Provide muscle contraction control.

Bromethalin Toxicity

• Bromethalin is a rodenticide that is used in baits.
• The toxin blocks mitochondrial energy production and causes cerebral edema, potentially leading to neurological signs.
• Clinical signs include muscle tremors, hyperthermia, hyperesthesia, excitability, and seizures.
• At lower doses, signs can take 2-7 days to appear and include CNS depression with possible ataxia, paresis, or hindlimb paralysis or coma.

Treatment for Bromethalin Toxicity

• Decontamination: induce vomiting and use activated charcoal.
• Manage CNS edema and seizures with mannitol, corticosteroids, and furosemide.
• Use diazepam and barbiturates if necessary, particularly during a high dose syndrome.
• The prognosis is often more severe if the animal is comatose or paralyzed versus a mild case, with surviving animals sometimes able to recover after having subtle neurological signs persist for a time, depending on the degree of toxicity.

Metaldehyde Toxicity

• Metaldehyde is a molluscicide used in baits for slugs and snails.
• Often combined with methiocarb.
• Dogs find the baits more attractive than cats.
• Clinical signs may include initial depression, salivation, vomiting, diarrhea, followed by hyperesthesia, muscle tremors, hyperthermia, ataxia, convulsions, death from respiratory paralysis (usually after deepening depression and narcosis). Liver failure is possible in surviving animals.

Treatment for Metaldehyde Toxicity

• Decontamination, induce vomiting, and use activated charcoal.
• Control CNS edema and seizures with mannitol, corticosteroids, and furosemide.
• Use diazepam or barbiturates if needed, and monitor for hyperthermia.
• Provide supportive care.

Sodium Monofluoroacetate (Compound 1080) Toxicity

• Compound 1080 is a potent rodenticide used in predator control, primarily for poison collars on sheep and goats.
• The compound inhibits the enzyme aconitase, blocking the Krebs cycle (oxidative energy production).
• Clinical signs vary, but typically include severe effects on the central nervous system (CNS) and heart.
• Animals affected tend to show more rapid effects on the heart.

Treatment Strategies for Compound 1080

• Decontamination (using activated charcoal) is dependent on timing.
• Provide supportive care, monitoring, and supportive treatments.

Chlorinated Hydrocarbons (DDT) Toxicity

• Chlorinated hydrocarbons (like DDT) are insecticides with high lipid solubility in the environment.
• Egg shell breaking (especially in wild birds).
• The effects on animals usually involve lower action potential thresholds.
• This causes changes in the CNS and can cause excitatory signs similar to strychnine.

Treatment for Chlorinated Hydrocarbons Toxicity

• Wash the animal in order to help with decontamination
• Use activated charcoal and be sure to adjust the dose.
• Provide seizure control with diazepam or barbiturates.
• Treat for hyperthermia and any possible acidosis, and provide supportive care.

DEET Toxicity

• Excessive exposure to high concentrations of DEET can cause progressive peripheral and central nervous dysfunction, affecting the nervous system progressively (excitable).
• Ant and Roach baits: not usually a concern due to low doses.
• Birth Control pills (especially iron-containing placebo pills) and Silica Gel Desiccants may cause mild gastrointestinal upset from ingestion.
• Glow Toys, soap, and mild detergents are mostly not a cause for alarm, but can cause mild gastrointestinal effects if ingested.

Cyanoacrylate (Super Glue) Toxicity

• Super glue polymerizes instantly on skin and mucous membranes.
• It becomes inert.
• The glue and its activation process creates heat and irritant vapors.
• Individuals may develop sensitivities to the materials.
• Treatment involves washing affected areas (eyelids separate in 1-4 days). For skin contact, use mineral oil/vegetable oil. For mouth contact, let it wear off on its own.

Topical Medications

• Zinc oxide ointment: Minor concern; vomiting if the patient has a reaction.
• Steroid ointments: Minor concern.
• Antibiotic ointments: Minor concern.
• Dilute tea tree oil (Melaleuca): Moderate concern.
• Pyrethrin/permethrin: Moderate concern (may have nerve-twitching signs on animals).
• Concentrated tea tree oil (Melaleuca): Moderate concern.

Tea Tree Oil Toxicity

• Tea tree oil is a complex mixture of bioactive phytochemicals.
• Signs appear 2-8 hours after exposure including CNS signs (e.g., weakness, depression, ataxia, tremors), hypothermia, and liver failure in rare instances.
• Treatment for mild cases involves washing the skin with soap and/or using activated charcoal (even if exposure is dermal).
• Intravenous lipids are sometimes necessary for severe cases of lipid-soluble toxicity.

Citrus Oil (D-Limonene) Toxicity

• Clinical effects may include: eye/skin irritation, salivation, muscle weakness, tremors, shivering, ataxia, and hypothermia if in a cool environment.
• There is no specific mechanism known.
• Treatment is similar to tea tree oil: wash repeatedly using warm water and soap and monitor body temperature, maintain a warm environment, and provide IV fluids as needed.

5-Fluorouracil (5-FU) Toxicity

• 5-FU inhibits DNA/RNA synthesis and is rapidly absorbed from the gastrointestinal tract (GIT).
• Cats are extremely sensitive, and signs can appear in 1-5 hours.
• Common symptoms include vomiting, GIT membrane sloughing, multiple organ failure, seizures, pancytopenia, and death often within 7 hours or less.

Treatment for 5-FU Toxicity

• Antidote uridine triacetate (Orphan Drug, available on a per patient basis.)
• Intravenous (IV) fluids.
• Gastrointestinal protectants.
• Anticonvulsants (barbiturates, propofol, gas anesthesia).
• Antibiotics if the patient survives and becomes leukopenic. Prognosis is poor, particularly for cats.

Medicated Patches (High Concentration)

• High concentration medicated patches pose a risk due to concentrated dosage.

Cigarettes Toxicity

• Ingestion of tobacco (cigarettes) involves nicotinic effects and LD50 = 9.2 mg/kg, needing to consider the size of the affected animal.
• Early signs can include vomiting, salivation, diarrhea, and CNS excitement (tachypnea, tachycardia).
• Neurological collapse and cyanosis, or weakness with tremors in addition to respiratory paralysis, can also appear.

Polyurethane Glue (Gorilla Glue) Toxicity

• Ingested polyurethane glue can cause stomach blockage.
• The volume increases dramatically, and it forms a solid mass in the stomach, preventing it from passing.
• Activated charcoal and emesis are not effective treatments.
• Surgical intervention is required.

Acetaminophen Toxicity

• Overdose of acetaminophen (usually found in Tylenol products) is associated with Liver failure in animals.
• Cats are more sensitive than dogs.
• Treatment involves using activated charcoal if the absorption of the compound hasn't been too rapid.
• If the absorption is too rapid, it won't be effective. This may mean providing supportive respiratory care, as well as general support (O2, IV fluids, blood transfusion, anti-emetics).
• Include liver support, such as SAMe, or silymarin for a period of 2-4 weeks and sometimes even N-acetylcysteine (NAC) for 48 hours. Use methylene blue if MetHb is severe.

Vitamin A Toxicity

• High doses of Vitamin A, often stemming from raw fish liver ingestion, will cause gastrointestinal irritation and issues, particularly in cats.
• Signs include anorexia, lethargy, weight loss, neck/limb pain issues, or skin/reproductive problems, especially in animals fed high raw liver diets.

Vitamin D3 Supplemental Toxicity

• Some Vitamin D3 supplements will cause issues if ingested in high concentrations
• Toxicity can often cause several issues including anorexia, lethargy, as well as PU/PD, hypercalcemia, and hyperphosphatemia.
• Treatment involves decontamination measures (activated charcoal), aggressive supportive care (IV fluids, diuresis with furosemide, monitor Ca and P frequently), possible use of Prednisolone and/or Pamidronate for more severe cases.

Household Batteries (Ingestion)

• Emesis is often not useful and can make matters worse, if the battery is intact and small. Leave intact objects in the GI system if they are small enough and don't pierce the lining during swallowing.

Ethylene Glycol (EG) Toxicity

• Ethylene glycol (antifreeze) is a common toxin.
• The sweet taste of EG attracts animals.
• The primary phase is CNS depression, followed by acidosis (metabolization creates glycolic/glyoxylic/oxalic acids).
• This can eventually lead to renal failure.

Treatment for Ethylene Glycol Toxicity

• Decontamination using activated charcoal is typically limited by how rapidly the ingestion happened initially when the compound was absorbed.
• Use IV fluids, and correct acidosis using sodium bicarbonate.
• Alcohol dehydrogenase inhibitors (4-methyl-pyrazole or fomepizole) may be used to treat this toxicosis. These should be used in conjunction with the ethanol dosages based on severity.

Antifreeze Toxicity (Others)

• Methanol and windshield wiper fluid, containing more than water and is often used to mix with antifreeze solutions, lead to CNS toxicities.
• Differences in methanol metabolism will potentially limit or avoid neuro issues, but other animals are often more dramatically affected.

Chocolate (Cacao) Toxicity

• Ingestion of cocoa, including theobromine, caffeine, and theophylline, can cause mild/severe toxicity.
• Symptoms often include agitation, vomiting, diarrhea, increased heart rate and blood pressure, tremors, seizures, and possibly even cardiovascular issues.
• Treatment is supportive, targeting decontamination (charcoal), and correcting any cardiac arrhythmias or imbalances.

Corrosives (Caustic Acids & Bases)

• Corrosives, especially acids and bases, can cause immediate intense pain and irritation.
• Acids will often cause coagulative necrosis, while bases lead to liquefactive necrosis. The espohagus is typically highly sensitive but also the stomach linings depending on the amount of exposure.
• Do NOT induce vomiting as it can severely increase the degree of tissue and intestinal damage.
• Emesis should be avoided in these cases. Supporting fluids and protecting the affected areas are crucial.

Laundry Pods Toxicity

• Laundry detergent pods can cause esophageal, gastrointestinal, and skin ulcerations, and may cause respiratory issues (acidosis, depression) due to chemicals like propylene glycol.
• Cationic detergents (using quaternary ammonium cations) are caustic in high concentrations, and ingestion leads to neuromuscluar blockage, leading to oxidative cytotic issues potentially.

THC Toxicity

• THC indirectly affects the heart and the brain's thermal regulation, often causing issues such as bradycardia or tachycardia, hyperthermia, or hypothermia, as well as other GI effects.
• Diagnosis is often based on the history of exposure and clinical signs, but there are no standardized diagnostic measures at the present time in most cases.
• Sometimes, GC/MS or LC/MS can be helpful, but this is often unfeasible or too late at point of animal intoxication.

Tilmicosin Toxicity

• Tilmicosin, though used for sedative purposes in cattle, can have several toxic properties at high doses in any animal, including the depletion of intracellular calcium.
• This can lead to negative inotropic effects, increasing heart rate and negatively affecting the contractility of the heart.
• This medication can be exacerbated by epinephrine and is dose/route dependent.

Chloramphenicol Toxicity

• Chloramphenicol is a potent medication that can lead to a reversible bone marrow suppression when used in high doses in animals or humans, and causes a dose-related (amount and duration of use) suppression in the bone marrow in the precursor cells.
• Humans and animals can suffer from aplastic anemia as a result, but the condition can often be reversed when the treatment is stopped, and in other scenarios, there are often modified versions that do not produce such severe side effects.

Drug Potential Harm to Pregnant Animals

• Some medications such as corticosteroids and prostaglandins can be harmful to pregnant animals, sometimes causing abortion, or potentially impacting the fetus or maternal respiratory function if administered inappropriately.

Potent Sedatives/Anesthetics

• Etorphine is an extremely potent opioid, is 1000-3000x more potent than morphine, often to immobilize/sedate wildlife, or reduce pain/discomfort in severe cases.
• Use of this medication when alone or lacking proper support is dangerous and should be avoided. It can quickly cause death in cases of exposure in humans or animals.
• The reversing agent naloxone (Narcan) is a crucial emergency tool in such scenarios. Rapid response is vital.

Xylazine Toxicity

• Xylazine is a sedative often given to cattle and horses.
• A toxic level can lead to hypotension, sinus bradycardia, CNS depression, apnea, and potentially convulsions, particularly if ingested via mucous membranes or IV.

Detomidine Toxicity

• Detomidine is a sedative used in cattle and equine sedations.
• Signs of toxicity include hypotension, sinus bradycardia, CNS depression, apnea, and convulsions.
• Similar to xylazine, potential risks of exposure can cause issues with intravenous (IV) use, or mucous membrane exposure.

Additional Toxins:

• Citrus Oil (D-Limonene): Eye/skin irritation, salivation, muscle weakness, tremors, and hypothermia in cool environments.
• Laundry detergents: High concentrations (cationic detergents) can cause potentially severe systemic effects (neuromuscular/oxidative toxicity).
• This is not an exhaustive list. Other potentially toxic substances, including those of plant and animal origin are omitted in order to be concise.

Test your knowledge on veterinary toxicology and the treatment options for various poisons affecting animals. This quiz covers key topics like Cholecalciferol toxicity, Strychnine poisoning, and common signs of toxicity in pets. Enhance your understanding of clinical signs and management strategies in veterinary emergencies.