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Dispensing Errors in Veterinary Medicine


Therapeutic substitutions

  • Although switching from tablets to capsules or from brand to generic is perfectly acceptable (in some cases) in veterinary medicine, there are a few things to consider:
    • Ensure that the substitution does not have an unintended impact on adherence and the human-animal bond. (ex., bigger size, inappropriate ingredient, bitter taste, etc)
    • Ensure the prescribing veterinarian understands the allowance for substitution
  • Be aware of veterinary-only drugs of common drug classes in human medicine
    • NSAIDS and fluroquinolones are commonly prescribed in both human and veterinary medicine but the drugs selected are completely different depending on the species.
    • Example: carprofen should not be substituted for ibuprofen for a canine patient


Prescription Errors

  • Veterinary Terminology
    • SID = once daily
    • FS = female spayed
    • MC = Male castrated 
    • Bolus = very large dose
  • Allometric dosing – weight based dosing (for the most part)




 Levothyroxine (most common medication error)
  • Dosed every 12 hours in veterinary medicine instead of every 24 hours
  • Usually dosed in mg instead of mcg (canines have a much larger dose than humans)
  • Still see grain and gram errors
  • “This dose is too high” 
 Trimethoprim/Sulfamethoxazole (Bactrim)
  • Referred to as “TMS”
  • In veterinary medicine dose is based on combination strength
 Amoxicillin/Clavulanate (Clavamox)
  • Dose is based on combination strength
  • Clavamox: 4:1 ratio
  • Augmentin shares a variety of ratios
  • May be written as just “Hydrocodone”
  • Combination products with APAP may be dispensed instead which could cause toxicity issues
 Insulin and Insulin Syringes
  • Inappropriate substitutions
  • Serious and potentially life-threatening errors can occur if the wrong syringes are sold or dispensed with insulin (U-40 vs. U-100)


Common “look alike-sound alike” drugs in veterinary medicine

  • Enalapril and Anipryl (Selegiline)
  • Convenia (Cefovecin) and Cerenia (Maropitant)
  • Zeniquin (Marbofloxacin) and Sinequan (Doxepin)