As pet owners, we always want to ensure the health and wellbeing of our feline friends. One of the most common vaccinations given to cats is the FVRCP vaccine, also known as the distemper shot. This vaccine helps protect cats against several serious illnesses, including feline viral rhinotracheitis, calicivirus, and panleukopenia. However, a question that many pet owners ask is, does the distemper shot calm cats down? In this comprehensive guide, we will explore the facts and myths surrounding this topic.

What is Distemper?

Distemper is a highly contagious and serious disease that affects the respiratory, gastrointestinal, and nervous systems of cats. It can be spread through the air, through direct contact with infected bodily fluids, or through contaminated objects. Symptoms of distemper in cats include fever, coughing, sneezing, vomiting, diarrhea, and seizures. Without proper treatment, distemper can be fatal.

Does Distemper Shot Calm Cats Down
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How Does Distemper Affect Cats?

Distemper, also known as feline panleukopenia, is a very contagious viral infection among kitties. This disease is kind of like an extreme flu, causing vomiting, high fever, loss of appetite, diarrhea, and one extremely tired kitty. Adult cats may be able to survive, but sadly distemper often takes a fatal toll on young kittens.

The Distemper Shot

The distemper shot, also known as the feline distemper vaccine, is a vaccine that is given to cats to protect against distemper. The vaccine contains a weakened or inactivated form of the virus, which triggers the immune system to produce antibodies that will protect the cat if it comes into contact with the real virus. The distemper shot is typically given as part of a series of two or three vaccines, spaced several weeks apart, with annual boosters recommended to maintain immunity.

Distemper Shot Schedule

Feline distemper is often offered in an upper respiratory combination vaccine, so cats only have to get stuck one time. As a kitten, they should get the first inoculation at 8 to 9 weeks of age, according to the Arizona Humane Society. They’ll get another dose around 11 to 12 weeks old and then a final distemper or combo shot at 14 to 15 weeks of age. After that, they’ll need an annual distemper or combo booster, depending on which one the vet offers. If you’re unsure of your kitty’s past and have no vaccination records, your veterinarian might give them two doses of the distemper or combination vaccine, each one at three weeks apart. From there, they’ll be good to go for this particular vaccination until it comes time for their annual booster.

Does the Distemper Shot Calm Cats Down?

There is limited evidence to support the idea that the distemper shot has a calming effect on cats. Some pet owners and veterinarians have reported that cats seem more relaxed and calm after receiving the vaccine, while others have not observed any noticeable changes. However, it’s important to note that the effects of the distemper shot on a cat’s behavior can be influenced by a number of factors, such as the cat’s age, personality, and overall health.

Possible Explanations for a Calming Effect

There are several possible explanations for why some cats may seem calmer after receiving the distemper shot. One possibility is that the shot may have a sedative effect on some cats, due to the stress and discomfort of the vaccination process. Another possibility is that the shot may have a placebo effect, with the cat’s behavior improving simply because the owner believes that it should.

Is the Calming Effect of the FVRCP Vaccine Safe for Cats?

The calming effect of the FVRCP vaccine is generally considered safe for cats, as the amount of acepromazine in the vaccine is small and well-tolerated by most cats. However, as with any medication, there is always a risk of side effects, and some cats may experience adverse reactions to the acepromazine in the vaccine. If you notice any unusual symptoms in your cat after receiving the FVRCP vaccine, such as vomiting, diarrhea, or lethargy, it is important to contact your veterinarian for advice.

Vaccine Side Effects

Side effects of the distemper booster are similar to most other vaccinations. Cats might be a little sore at the injection site, so be careful handling them. They may not feel like eating dinner the day of their vet appointment, but leave it out for them in case their appetite comes back. A mild fever and lack of activity are common for a day or two, although if they still haven’t returned to their normal self after several days, it’s time to call your veterinarian.

Serious Problems

Once in a great while, cats have allergic reactions to their vaccines. If their body doesn’t tolerate it, you’ll know within several minutes or up to an hour after the shot. They’ll start scratching, pawing at their face, foaming at the mouth, have difficulty breathing, and may faint. Sarcomas are also possible, although equally as rare. These tumors form at the injection site and develop several weeks or months after receiving the vaccination. It’s normal for the jabbed area to feel a little swollen for a few days, however, if it continues to get hard and doesn’t go away, let your veterinarian know as soon as possible.

Can the Distemper Shot Cause Any Side Effects in Cats?

Like any medical procedure, the distemper shot can cause side effects in some cats. The most common side effects include mild pain or swelling at the injection site, low-grade fever, and decreased appetite. These side effects are usually short-lived and can be managed with supportive care from a veterinarian.

Does Distemper Shot Calm Cats Down
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What Are the Benefits of Getting Your Cat Vaccinated Against Distemper?

Getting your cat vaccinated against distemper provides numerous health benefits. It not only protects your cat from contracting the virus but also helps prevent the spread of the disease to other cats. In addition, vaccinated cats are less likely to require veterinary care for distemper-related health issues, saving pet owners money in the long run.

Is the distemper shot necessary for cats?

Yes, the distemper shot is necessary for cats to protect them against feline distemper, a highly contagious virus.

Can the distemper shot cause side effects in cats?

Yes, the distemper shot can cause side effects in some cats, including mild pain or swelling at the injection site, low-grade fever, and decreased appetite. However, these side effects are usually short-lived and can be managed with supportive care from a veterinarian.


The FVRCP vaccine is an important tool for protecting cats against serious illnesses, including feline viral rhinotracheitis, calicivirus, and panleukopenia. While some pet owners believe that the vaccine has a calming effect on their cats, the scientific evidence on this topic is mixed. If your cat experiences anxiety or fear during veterinary visits, the FVRCP vaccine may help calm them down, but it is important to keep in mind that the effect is generally mild and temporary. If you have any concerns about the FVRCP vaccine and its effects on your cat, be sure to discuss them with your veterinarian.