It is a little known fact that the FDA Center for Veterinary Medicine (CVM) currently lacks the authority to require the drug sponsor to address issues through label changes, formulation adjustments, or other measures to enhance safety.

According to the FDA CVM: "...in the FY 25 Legislative agenda, FDA is proposing that the FD&C Act be amended to authorize CVM to require animal drug sponsors to make safety-related labeling changes based on new safety information that becomes available after approval of an animal drug; to require animal drug sponsors to develop and implement a Risk Evaluation and Mitigation Strategy (REMS), a drug safety program for drugs with serious safety concerns and for which interventions beyond FDA-approved labeling are necessary to ensure the safe use of the drug; and to require animal drug sponsors to conduct post-approval studies of animal drugs to assess a known or potential serious safety risk. Unlike for human drugs, FDA does not currently have these authorities for animal drugs. Additionally, these authorities would address the situation where multiple sponsors are marketing an animal drug or class of drugs with similar safety risks. In such cases, FDA has found the current process for negotiating changes in labeling or ensuring implementation of other voluntary, post-approval actions to mitigate risks to be lengthy and to create an uneven playing field as sponsors of similar drugs agree to different postapproval actions on different timelines, resulting in inconsistent practices and labeling information.
Please see: https://www.fda.gov/media/176924/download for additional information."

Still, it is imperative that caregivers (veterinary professionals and owners alike) report adverse events, both to the marketing authorization holder AND to the FDA CVM. Only then can safety signals be identified and potentially timely addressed.

If you are inclined to research reported adverse events with a particular veterinary product, please see the EMA's EudraVigilance database which actually summarizes adverse event reports from around the world: www.adrreports.eu.