Veterinary Pharmacology and Toxicology
Principles first
Pharmacology questions test pharmacokinetics (absorption, distribution, metabolism, excretion - ADME) and pharmacodynamics (what the drug does at the target). Know how route affects onset and bioavailability, how hepatic metabolism and renal clearance shape half-life, and how protein binding affects free drug concentration.
Drug classes to know
- Antimicrobials: beta-lactams, tetracyclines, aminoglycosides, macrolides, sulphonamides - mechanism, spectrum, and key cautions.
- NSAIDs: COX inhibition; species differences in toxicity.
- Anaesthetics/sedatives: dose–response, monitoring.
- Antiparasitics: mode of action and resistance.
- Corticosteroids: anti-inflammatory vs immunosuppressive doses.
Toxicology essentials
Know common toxicants and their antidotes or management: organophosphates (atropine), anticoagulant rodenticides (vitamin K1), lead, chocolate/theobromine in dogs, and plant toxins. Understand dose–response, threshold, and species susceptibility.
Traps
- Withdrawal periods differ by species, product, and route - never generalise.
- Species-specific toxicity: e.g., cats lack glucuronidation capacity, making some drugs (e.g., paracetamol/acetaminophen) dangerous.
- Confusing bacteriostatic with bactericidal.
- Assuming a drug safe in one species is safe in another.
Worked rule of thumb
For any drug question, ask: Which species? Which route? Which dose? Is there a withdrawal period for food animals? If the stem omits species, the answer may hinge on a species-specific caution.
Study approach
Build a drug table: class, mechanism, key adverse effects, contraindications, and food-animal withdrawal.