ADVERSE EVENT REPORTING

Practitioners can further contribute to clinical research by reporting adverse events, which include any undesirable response to a therapeutic or preventive intervention such as a drug, vaccine, therapeutic procedure, dietary supplement, food, diagnostic test, or medical device. Adverse drug events include medication errors. The term adverse generally implies a serious nature to the event such that the quality or quantity of life is affected. However, less serious side effects also are undesirable. Therapeutic failure (e.g. to compounded products or vaccines) also might be considered an adverse event.

It is important to report adverse events because although they might be discovered during the approval process, they more commonly emerge with postmarket surveillance when thousands of patients are receiving the product. This surveillance vitally depends on reporting by practitioners or clients. The only mechanism by which these reports will find their way back to the profession is if they are reported to an agency that collects, analyzes, and re-reports the data. This will only happen with practitioner input.

FDA-and USDA-regulated products

For drugs (animal, human, or compounded) and foods, the appropriate agency for reporting adverse events is the FDA Center for Veterinary Medicine (CVM) ( http://www.fda.gov/cvm/adereporting.htm). For vaccines (and some other biologics), the United States Department of Agriculture ( http://www.aphis.usda.gov/) is the appropriate agency. By law, each manufacturer must report the adverse event information to its respective regulatory agency. The ASPCA also sponsors a poison control center. Although the center maintains extensive records regarding any type of adverse event, data collection is generally fee-based (with the intent of providing therapeutic advice), and the information is not accessible to the public.

Practitioners often express concern that clients will be less likely to use products if counseled regarding adverse events or that such counseling paves the way for future litigation should an adverse event occur. Yet data from human medicine indicate that patients are more likely to become angry with their caregivers if information is withheld. Informed clients tend to be happier clients. Although reporting adverse events is particularly critical immediately after a new drug, particularly a new drug class, is approved, practitioners should remain diligent and report all adverse events. It is only through continued data collection that more subtle adverse events might emerge, and only then might safety differences among drugs within the same class (e.g. NSAIDs) become evident.

Adverse vaccine events reported by practitioners or their clients are analyzed annually and then reported to the profession through veterinary journals. The path for reporting adverse drug events to the profession is less clear and would benefit from practitioner direction. Adverse drug events reported to the FDA-CVM have been posted annually and cumulatively on its Web site. However, because pharmaceutical companies do not provide information regarding the number of units of each drug sold, a popular drug might be interpreted as having a greater incidence of side effects, when, in fact, it is simply more commonly used.

Further, the cause and effect between the adverse event and the drug cannot always be confirmed through the reports, and reports are not always accompanied by risk factor information (e.g. overdose, underlying disease). Disconcertingly, the FDA-CVM has recently removed information regarding the incidence of adverse events to products from its Web site ( http://www.fda.gov/cvm/ade_cum.htm), markedly limiting the usefulness of the information to practitioners. Equally important to practitioners reporting adverse events is the availability of collated and analyzed data in a useful format. Thus, in addition to reporting adverse events, our responsibilities include insisting (perhaps by working with the AVMA) that the FDA-CVM and manufacturers provide and maintain a robust reporting system that returns relevant information to the profession in a timely, user-friendly fashion.

Medication errors

Medication errors, including administration of the wrong dose, interval, route, medication, or drug or to the wrong patient, are a problematic subset of adverse events. In human medicine, up to 30% or more of adverse events associated with serious injury are preventable in that they reflect medical errors on the part of caregivers.^1,2 As such, these adverse events were preventable. Our profession has no information regarding the incidence and impact of medication errors. Yet they occur.

As we improve our adverse event-reporting activities, we need to gain the self-confidence that will allow self-critique and, thus, facilitate medication error reporting. For example, because medication errors are more likely to occur (and more likely to be dangerous) in critical care patients, a Web site that allows anonymous entry of the adverse incident might be considered by veterinary emergency and critical care specialists. Such a Web site might begin the dialogue necessary for recognizing a potential problem.