Antibiotics are medications that help fight bacterial infections in animals. These medications come in different forms - tablets, liquids, topical preparations (eye drops, skin ointments, etc) or injections - and work in various ways to either kill bacteria directly or stop them from multiplying.

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Your veterinarian will prescribe antibiotics when they believe your pet has a bacterial infection that won't clear up on its own. Common situations include skin infections, urinary tract infections, respiratory infections, or infected wounds. However, it's important to understand that antibiotics don't work against all types of infections. For example, viruses account for many common infections and antibiotics don’t help at all against viruses. Symptoms of viral and bacterial infections can be very similar and so it may be hard for your veterinarian to know just by looking at your pet whether antibiotics are required or not. They will use their clinical knowledge and experience when making decisions but may also need to take samples to send off for testing.

Different antibiotics are needed for different types of bacteria. For some conditions, your veterinarian will be confident in their diagnosis and know exactly which antibiotic is best to use. In other scenarios, your vet may need to run further tests to diagnose the exact problem(s) affecting your pet. For serious infections, your veterinarian will use their clinical judgement to immediately prescribe what they feel is the most appropriate antibiotic for the clinical scenario and body system affected. However, before, or during, treatment they make take samples to send off for testing – to check which bacteria are present and which is the best antibiotic to use (known as culture and sensitivity testing) and may then change the antibiotic depending on the results that come back. For less serious infections , your veterinarian may delay starting antibiotic treatment while they obtain the results of culture and sensitivity testing, so as to start off with the most appropriate antibiotic for your pet’s infection. Your vet will also take into account any other medical conditions your pet has and any other medication they may be on. As you can see – it’s not straight forward, every case is different, and your veterinarian has a lot of factors to consider.

When an animal is unwell, it’s natural to want to do all we can to help them and as quickly as possible but giving antibiotics when they are not needed can cause extra problems – both for the affected pet and for the animal and human population as a whole. Antibiotics don’t just kill “bad” bacteria. They can also harm the “good” bacteria that your pet’s body needs. Antibiotics can damage the natural bacteria in the gut – that are important for the pet’s digestion. Use of antibiotics often results in diarrhea or vomiting, that can last quite a while. Also, our use of antibiotics has resulted in bacteria developing resistance to them – more on this below…

When bacteria become resistant to an antibiotic, it means the antibiotic will no longer work against an infection caused by those bacteria. The more that antibiotics are used, the more likely is the development of resistance. As many antibiotics are used in animals and people, antibiotic resistance is a serious issue that has consequences for the health of animals and people. Veterinarians, doctors, pet owners, farmers and the general public all have a responsibility to use antibiotics responsibly, so as to safeguard their effectiveness for us and for future generations of animals and people. It is now recognized that the health of people is connected to the health of animals and the environment, a concept known as “One Health”. The goal of One Health is to encourage the collaborative efforts of multiple disciplines-working locally, nationally, and globally to achieve the best health for people, animals, and our environment. Veterinarians are key to bridging the gaps between these three components of One Health. Bacteria multiply quickly, and their genetic makeup changes with each generation. Every time bacteria are exposed to antibiotics, some may survive and pass on their resistant genes to other bacteria. The problem can be compounded because bacteria can become resistant to several different antibiotics . For example, “super bugs”, such as MRSA have come about because bacteria that used to be killed by antibiotics, are now resistant to antibiotics. This means that if an animal, or a human, contracts an infection such as MRSA, then doctors and veterinarians are very limited in what they can do to stop the infection and consequently lives are lost that previously could have been saved. To reduce the development of bacterial resistance, doctors and veterinarians are increasingly careful about when they prescribe antibiotics and aim to ensure that they choose the most appropriate type for the situation. This process, known as antibiotic stewardship, can lead to short delays in treatment, while veterinarians await lab results. There may be times where your veterinarian opts to wait and see if an infection can be cleared without antibiotics. Minor infections are often self-limiting (the body's immune system effectively clears them in good time) , but inevitably there will be times when antibiotics are required and the delay in treatment may be frustrating to you as the pet owner . Veterinarians never make these decisions lightly and it’s a big responsibility trying to balance optimal treatment with the patient in front of them vs. ensuring good antibiotic stewardship to protect the effectiveness of antibiotics for the wider population. Please bear this in mind when talking to your veterinarian and know that they are doing their best to navigate this complex situation whilst providing optimal care for your pet. As a pet owner, you can help by never giving your pet antibiotics without a prescription and always completing the full course as prescribed. If you have any unused antibiotics, return them to your veterinary practice or pharmacy for safe disposal. Disposing of antibiotics via wastewater (e.g. by flushing them down the toilet) can pollute the environment and help to spread antibiotic resistance.

As a responsible pet owner, there are several important steps you can take to help combat antibiotic resistance. Always give the complete course of antibiotics as prescribed by your veterinarian, even if your pet seems better. Stopping too early can allow some bacteria to survive and potentially become resistant to future antibiotic treatments. Always give the medication at the scheduled times and dosages, and follow any special instructions, such as giving it with food or on an empty stomach. Never use leftover antibiotics from previous prescriptions or share antibiotics between pets. It's also important to trust your veterinarian's judgment when they decide not to prescribe antibiotics. They are making this decision based on their medical expertise and commitment to responsible antibiotic use. If you have questions about your pet’s care then be sure to raise these with your veterinarian, who will be happy to help and support you.

Like all medications, antibiotics can have side effects. Common ones include mild digestive upset, such as vomiting or diarrhea. Some pets might show decreased appetite or become more tired than usual. While these side effects are usually mild, it's important to contact your veterinarian if they become severe or if your pet shows signs of an allergic reaction, such as difficulty breathing or severe skin reactions.

When antibiotics aren't necessary, your veterinarian may recommend other treatment approaches. These might include supportive care to help your pet's immune system fight off the infection, topical treatments for skin conditions, or specific medications targeted at the actual cause of the illness (such as anti-viral medications for viral infections). Sometimes, simply allowing time for your pet's immune system to work while keeping them comfortable is the best approach. There might be a need for treatment for any underlying conditions that have led to the infection, to help prevent recurrent infections.

Contact your veterinarian immediately if your pet shows any concerning symptoms while on antibiotics. These might include severe vomiting or diarrhea, loss of appetite lasting more than 24 hours, or any unusual behavioral changes. Also, if your pet's condition doesn't improve after a few days of antibiotic treatment, or if it worsens at any point, your veterinarian needs to know.

Your veterinarian might schedule a follow-up appointment, and sometimes repeat tests, to check your pet's progress during or after antibiotic treatment This helps ensure the infection is clearing up properly and allows them to address any concerns. They might also recommend probiotics to help maintain healthy gut bacteria during or after antibiotic treatment, as antibiotics can affect both harmful and beneficial bacteria in your pet's digestive system.