Why report side effects and lack of efficacy?

Reporting of side effects and lack of efficacy is the only way to monitor veterinary medicines after authorisation!

When a veterinary medicinal product is authorised, the approval is usually based on clinical trials performed in the target animal species. Despite the requirements for documentation prior to approval, it is not always possible to discover all potential side effects of a medicine prior to authorisation. This is partly because animals participating in clinical trials are specifically selected for e.g. age, concurrent diseases or lack thereof, and clinical trials are usually carried out over a relatively short period of time. Other times it is not possible to ensure representation of all breeds or weight categories within a species. Furthermore, participants in clinical trials are followed carefully throughout the trial to monitor their reaction and wellbeing, and to ensure that the medicine is given correctly. Once a medicine is marketed and used in the real world by veterinarians, farmers and animal owners, the situation is often different, and the medicine is now used in a much larger number of animals than what is possible to include in a clinical trial. All of this means, that new side effects may be seen after authorisation.

In other situations, a medicinal product which was previously effective is no longer as effective. Particularly for antibiotics and antiparasitics this may be a sign of antimicrobial resistance.

In both cases, new precautions may be necessary to minimise the risks and optimise efficacy.

Furthermore, in both situations your report is a very important contribution to ensure the continued safety and efficacy of veterinary medicines – also after the medicine has been authorised and marketed. Reporting of side effects and lack of efficacy is the only way for authorities to receive direct information from the end-users of the veterinary medicinal products.

Additionally, veterinarians have an obligation to report side effects under the Danish national legislation. See more in the menu “Veterinarians’ reporting obligations”