Contact your veterinarian immediately. If the reaction is severe — difficulty breathing, seizures, collapse, or severe swelling — seek emergency veterinary care right away. After your pet is stabilized, report the adverse event to the FDA through safetyreporting.hhs.gov or by calling 1-888-FDA-VETS (1-888-332-8387). Reporting helps the FDA identify safety issues that can lead to label changes or product recalls.

Dogs account for the majority of adverse event reports, followed by cats. This reflects both the larger pet population and wider range of medications for these species. Flea and tick products, pain medications (NSAIDs), and heartworm preventives are among the product categories with the highest report counts across all species.

Not necessarily. A drug used by millions of pets will have more reports in absolute numbers than a niche product, even if the actual rate of adverse events is lower. The FDA uses these reports as one of many tools to evaluate drug safety, looking for patterns and statistical signals rather than raw counts alone. Always consult your veterinarian before changing any medication.