What is step 1 of the prescribing cascade?

• A. Use a human medicine when animal-specific product is not available.
• B. The medication must be proven effective in at least three other species.
• C. The medication can be any licensed drug for any condition in any species.
• D. The medication prescribed for an animal should be licensed for treatment of that condition in that species.

Answer: (D)

The first step in the prescribing cascade is to use a medicine that is licensed for the animal’s species and for the specific condition being treated. This ensures the drug has been evaluated for safety and efficacy in that species, with clear dosing, administration, and labeling.

If there is no licensed option for that species and condition, you then consider other steps in the cascade, such as using a medicine licensed for another species or a human medicine with appropriate justification, or, if necessary, an unlicensed preparation.

So the principle is that the prescribed drug in this situation must be licensed for treatment of that condition in that species.