FDA is aware of adverse event reports in connection with Trifexis and continues to closely monitor them. It is very important to realize that reports of adverse events do not necessarily mean that the product caused the event. Other factors, such as existing disease, exposure to chemicals or contaminants, foods, or other medications may have triggered or contributed to the cause of the event. However, when FDA is able to establish a safety concern with an approved animal drug, it may take actions such as requesting the manufacturer changes the label to reflect this safety issue and provides information to veterinarians and animal owners about how to use the product more safely. FDA is reviewing all available information on Trifexis in order to determine if actions such as label changes need to be taken.