Updated September 25, 2023
Convenia® is widely used by veterinarians in Australia and other countries as a long-acting antibiotic for cats. Many vets rely on it, often believing it’s what pet owners prefer. However, despite its convenience, there are significant considerations that every cat owner should be aware of before agreeing to this treatment.
Perhaps you’ve never questioned your vet’s decision to use Convenia. After reading this, hopefully, you will be more informed and empowered to discuss the best options for your feline companion. Understanding the implications of using Convenia is crucial for responsible pet ownership and ensuring the long-term health of your cat.
Understanding Convenia: A Long-Acting Antibiotic
Convenia, also known by its generic name cefovecin, is a broad-spectrum cephalosporin antibiotic administered via injection. Its key feature is its long duration of action. Once injected, it binds to proteins in the bloodstream, providing antibiotic effects for up to 14 days.
When Convenia was first introduced, it was hailed as a revolutionary solution, particularly for cats and dogs who were difficult to medicate orally. It seemed to address the common concern of missed medication doses by pet owners.
Indeed, Convenia is a potent and effective antibiotic. It generally boasts a good safety profile and is relatively cost-effective, especially for smaller animals like cats. These advantages have contributed to its widespread adoption in veterinary practices globally.
However, the very characteristic that makes Convenia appealing – its convenience – is also the source of its potential drawbacks.
The Convenience Paradox: Why Convenia Isn’t Always Ideal
While the ease of a single injection is attractive, there are compelling reasons why cefovecin might not be the optimal antibiotic choice in many situations. The convenience factor can sometimes overshadow more appropriate treatment strategies. Consider some of the common thought processes that might lead a vet to choose Convenia:
- “This cat will be challenging to pill.”
- “The owner may struggle to administer oral medication consistently.”
- “Convenia ensures treatment compliance and reduces the risk of failure.”
- “Owners prefer injections over oral medications.”
- “Practice policy dictates using Convenia for certain conditions.”
- “If I don’t offer Convenia, the client might seek treatment elsewhere.”
While some of these assumptions might hold true in certain cases, relying on convenience alone can lead to the overuse and misuse of Convenia. It’s sometimes used even when antibiotics are not truly necessary, such as for:
- Simple diarrhea
- Uncomplicated cystitis (lower urinary tract signs) in young cats
- Routine surgical or dental procedures
Furthermore, the practicalities of vial usage can also influence prescribing habits. Once a vial of Convenia is opened, it has a limited shelf life. The pressure to use the remaining medication to avoid wastage can sometimes lead to its use even when a different antibiotic might be more suitable.
So, what are the specific concerns that make Convenia a less-than-ideal choice in many scenarios? There are two primary areas of concern: side effects and wider effects on antibiotic resistance.
1. Convenia’s Side Effects: The Prolonged Rollercoaster
The initial enthusiasm for Convenia was tempered by emerging reports of adverse reactions. Cefovecin shares a structural similarity with penicillin, meaning allergic reactions are possible. With most antibiotics, if an allergy occurs, you simply discontinue the medication. However, Convenia presents a unique challenge. It’s known to maintain detectable levels in the bloodstream for up to 65 days.
This prolonged presence means that if an adverse reaction occurs, it’s like being stuck on a rollercoaster you can’t stop. The effects can linger for an extended period.
It’s crucial to emphasize that Convenia remains a valuable and even excellent option in specific situations:
- Resistant Infections: When bacterial infections are known to be resistant to first-line antibiotics.
- Severe, Life-Threatening Illness: In critical situations where immediate and prolonged antibiotic coverage is essential.
- Medication Intolerance: When a cat absolutely refuses oral medication and other administration methods are not feasible.
Even with the knowledge of potential drawbacks, the author, a veterinarian, chose Convenia for his own sick cat when oral medication proved too stressful for both cat and owner. However, with a deeper understanding of the broader implications, a different approach might have been considered.
2. Convenia’s Wider Effects: Fueling Antibiotic Resistance
The more concerning aspect of Convenia use lies in its contribution to the growing global problem of antimicrobial resistance. This is an issue that often goes unmentioned in consultations, highlighting a need for greater awareness and open discussion.
Cefovecin is classified as a “highest priority critically important antimicrobial” by health organizations. This designation means it should be reserved as a third-line antibiotic, only used after first and second-line options have failed or when guided by culture and sensitivity testing. Culture and sensitivity testing involves taking a sample from the infection site, growing the bacteria in a lab, and testing its susceptibility to various antibiotics. This targeted approach ensures the most effective antibiotic is used, minimizing the risk of resistance development.
However, a study in Australia revealed a concerningly low rate of culture and sensitivity testing in veterinary practice – only 0.3% of the time. Even when tests were performed, Convenia was often started before the results were available.
The author acknowledges being part of this pattern, citing the challenges of convincing owners to incur the additional cost of testing (often over $100) and the delay in receiving results. The immediate desire to treat the animal often takes precedence.
Why Antimicrobial Resistance Matters: A Shared Responsibility
Antimicrobial resistance is a global health crisis that affects everyone. While human medicine and agriculture are often targeted as major contributors, the rate of antibiotic resistance in companion animals like dogs and cats is comparable to that in humans and even higher than in farm animals.
The use of third-generation cephalosporins like cefovecin is directly linked to the development of multidrug-resistant organisms in humans. Convenia’s long-acting nature exacerbates this problem. The extended period (up to 65 days) during which sub-lethal doses of the antibiotic are present in the body creates an ideal environment for bacteria to develop resistance mechanisms. It’s essentially a “boot camp” for resistance.
The implications are not limited to public health. Using Convenia when a narrower-spectrum, first or second-line antibiotic could be effective can promote resistance in your cat’s own bacterial flora. This means that when stronger antibiotics are genuinely needed later, even for serious conditions affecting you if you were to contract bacteria from your pet, they may be less likely to work.
Taking Action: A Path to Responsible Antibiotic Use
Addressing this issue requires a collaborative effort from both cat owners and veterinarians. Here are actionable steps to promote more responsible antibiotic use:
For Cat Owners:
- Communicate with your vet: Proactively inform your veterinarian if you are comfortable and capable of administering oral medications. Veterinary consultations can be rushed, and vets might default to Convenia assuming oral medication is not an option.
- Challenge assumptions about oral medication: Even if you initially doubt your ability to pill your cat, it’s often more achievable than you think. Managing chronic conditions like hyperthyroidism and kidney disease in cats frequently involves regular oral medication, demonstrating that most owners can adapt when necessary.
- Explore pill-giving techniques: Consult resources and guides on how to effectively give pills to cats. Enlisting a second person for assistance, even a neighbor, can significantly improve success rates.
- Consider alternative medication forms: If pills are truly problematic, inquire about liquid formulations of antibiotics, which are often easier to administer. Injections given daily at home are also a viable option that many owners, even elderly ones, can master.
- Discuss the necessity of antibiotics: Don’t hesitate to ask your vet if antibiotics are truly necessary for your cat’s condition. Explore alternative treatments when appropriate.
For Veterinarians:
- Engage in open communication: Actively ask owners about their preferences and capabilities regarding medication administration. Support owners who are willing to try oral medications.
- Re-evaluate antibiotic necessity: Critically assess whether antibiotics are truly indicated for every condition. Address the tendency towards risk-averse prescribing practices.
- Prioritize first-line antibiotics: When antibiotics are necessary, consider whether a lower or medium-priority antibiotic could be effective before resorting to Convenia.
- Promote culture and sensitivity testing: Educate clients about the benefits of culture and sensitivity testing for targeted antibiotic therapy, especially for recurrent or severe infections.
The intention is not to criticize veterinarians or present oneself as exemplary. The author admits to previously overusing Convenia. Systemic change requires support and information dissemination from regulatory bodies to busy veterinary professionals.
Ultimately, responsible antibiotic stewardship is a shared responsibility. By increasing awareness and promoting informed decision-making, we can ensure that Convenia and other important antibiotics are used judiciously, preserving their effectiveness for when they are truly needed to protect the health of our cats and the wider community.
Sources
Hardefeldt, L., Hur, B., Verspoor, K., Baldwin, T., Bailey, K. E., Scarborough, R., … & Gilkerson, J. (2020). Use of cefovecin in dogs and cats attending first‐opinion veterinary practices in Australia. Veterinary Record, 187(11), e95-e95
Norris, J. M., Zhuo, A., Govendir, M., Rowbotham, S. J., Labbate, M., Degeling, C., … & Ward, M. P. (2019). Factors influencing the behaviour and perceptions of Australian veterinarians towards antibiotic use and antimicrobial resistance. PloS one, 14(10), e0223534
Singleton, D. A., Rayner, A., Brant, B., Smyth, S., Noble, P. J. M., Radford, A. D., & Pinchbeck, G. L. (2021). A randomised controlled trial to reduce highest priority critically important antimicrobial prescription in companion animals. Nature communications, 12(1), 1-14
The National Centre for Antimicrobial Stewardship
* Defensive medicine pressures: Veterinarians sometimes feel pressured to practice defensively. The example of a limping dog with suspected bone cancer highlights how owner expectations and potential complaints can influence treatment decisions, sometimes pushing vets towards antibiotic use even when less aggressive approaches might be considered. This fear of negative repercussions can limit the willingness to deviate from standard protocols, including antibiotic prescription.
Have something to add? Comments (if open) will appear within 24 hours. By Andrew Spanner BVSc(Hons) MVetStud, a vet in Adelaide, Australia. Meet his team here.
