Amoxicillin For Cats: Dosages, Side Effects, and More

For many longtime cat guardians, amoxicillin for cats may not be a mystery. It is an antibiotic in the penicillin family that is used to prevent bacteria from growing. According to Tufts University and Medical News Today, it treats everything from bronchitis to Lyme disease to urinary tract infections in humans. Amoxicillin for cats is often used in kittens with skin infections, urinary tract infections, and ear infections.

When I met my vet Dr. Kelly Tierney (2014 class) of Shinnecock Animal Hospital asked what she thought about the drug, she paused. “I learned the drugs from my mentor that became my favorite drugs. He always used an antibiotic combined with clavulanic acid for diseases such as urinary tract infections and gastrointestinal infections. So I’d say newer vets are probably using Clavamox (an antibiotic containing clavulanic acid) instead of amoxicillin, but it’s really your vet’s call. “Depending on your veterinarian’s preferences, your cat may be on it right now. Here is the bullet on amoxicillin for cats.

A gray cat ready to take a pill from a human. Photography by radleyhebdon / istock.

When is amoxicillin necessary for cats?

At one point, amoxicillin was the updated version of penicillin (patented by Bristol-Myers, 1975). It was considered better as it would be active longer, according to PetMD. It is used to treat cats with bacterial infections such as wounds (such as animal bites), bladder infections, abscessed teeth, eye or ear infections, skin infections, and respiratory infections. It can be used for GI infections, but is not effective against parasites (such as tapeworms). Antibiotics are also usually recommended after surgery, but the Cummings Veterinary Medical Center at Tufts University states that they are prescribed on a case-by-case basis.

If your cat has been in a fight, has a scratch, has itchy ears or runny eyes, or scratches like crazy, a trip to the vet will determine the best treatment. Some conditions, like urinary tract infections, are elusive. If your cat is acting strangely, especially by urinating outside of its litter box, take it to the vet with a urine sample. He’s probably taking amoxicillin.

Amoxicillin dosage for cats

  1. Follow the schedule. One of the most important things about amoxicillin for cats is to make sure that you are giving the medication at the scheduled time and for the entire prescribed duration – even if your cat’s symptoms are gone. If you stop taking the drug before the prescribed end date, you will leave your cat vulnerable to an even worse disease that may not be treatable. The World Health Organization notes that antibiotic resistance is one of the greatest threats to global health!
  1. Never prescribe yourself. Let’s say your cat seems to have an infection similar to last year and you have amoxicillin from one of your diseases around the house. Amoxicillin for cats is not the same as amoxicillin for humans. Vetinfo reports that it could be toxic to your cat. Acknowledge the origin of any disease before treating it. It could be a viral infection. In this case, amoxicillin is useless.
  1. Get a second opinion. If you feel that your cat is taking a lot of antibiotics and not really getting better, contact another veterinarian. Along with a possible misdiagnosis, amoxicillin for cats and other antibiotics have side effects. Being on them for an extended period of time with no improvement could be a red flag that something is wrong.

Possible side effects of amoxicillin in cats

Antibiotics, including amoxicillin, can cause a number of side effects in cats. Because every cat is an individual, every cat reacts differently to amoxicillin. PetCareRX names the following side effects as the most common side effects of antibiotics: rashes, fever, kidney or liver damage, diarrhea, and vomiting.

Also, antibiotics can be especially difficult in the digestive system. Therefore, confirm whether your cat should take amoxicillin with or without food.

Additionally, Vetinfo advises that your cat could have dangerous complications if amoxicillin is taken while other antibiotics are in their system. And some cats are allergic to it. Monitor your cat closely while you are on medication and make your veterinarian aware of any unusual things – health or behavior.

What about treating your cat with alternative medicine?

Take your cat to the veterinarian right away if it appears sick or injured. According to Dr. However, Shawn Messonnier, author of the Natural Health Bible for Dogs and Cats and Diet Supplements for the Veterinary Office, there are holistic approaches that can primarily keep your cat healthy.

While we don’t advocate using natural alternatives to traditional medication, learning more about supporting your cat’s immune system can help you develop a healthy strategy for life. Amoxicillin for cats has many benefits, some side effects, and should always be taken as directed by a professional veterinarian. Close communication with your veterinarian is the best way to ensure that your cat’s amoxicillin treatment is doing the trick to ensure its health and wellbeing.

Thumbnail: Photography by Elenica / Shutterstock.

This piece was originally released in 2017.

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