Pharmacy and Pharmacology
The Pharmacy and Pharmacology domain tests whether you can handle veterinary drugs safely and perform dose calculations without error. Expect questions on drug classes and mechanisms, routes, pharmacokinetics, controlled substances, compounding, labeling, storage, and withdrawal times. The exam often frames these as a prescription to fill or a dose to verify.
Core rules
- Confirm the five rights before dispensing: patient, drug, dose, route, and time; add documentation and client instruction.
- Convert weights first: 1 kg = 2.2 lb. Most veterinary doses are mg/kg, not mg/lb.
- Check the concentration on the label every time; a 50 mg/mL suspension and a 250 mg/5 mL suspension are not interchangeable.
- Know common interactions: NSAIDs with corticosteroids, macrolides with other QT-prolonging drugs, and tetracyclines with antacids.
- Store according to label; some drugs need refrigeration, protection from light, or reconstitution within a set expiry.
Worked example
A 12 kg dog is prescribed amoxicillin 11 mg/kg PO every 12 hours for 10 days. The suspension is 50 mg/mL. Dose: 12 × 11 = 132 mg. Volume: 132 ÷ 50 = 2.64 mL per dose. Twice daily gives 5.28 mL/day; for 10 days, 52.8 mL. Dispense at least 60 mL so the client can complete the course.
Traps
Using mg/lb by mistake, misplacing a decimal, dividing by the wrong concentration, assuming a tablet can be split accurately, and ignoring food effects or withdrawal periods. For food animals, the withdrawal time is a legal label instruction, not a suggestion.