Side Effects of Pet Vaccines: What’s Normal & When to Call the Vet

Vaccinations play a vital role in protecting your pet from serious illnesses and helping them live longer, healthier lives. While most pets handle vaccines without issue, it’s natural for pet owners to wonder about potential side effects. Knowing what’s normal and what requires a call to the vet can give you peace of mind and ensure your pet’s well-being.

Common, Mild Vaccine Side Effects

It’s normal for pets to experience mild, short-lived reactions after receiving vaccines. These side effects typically appear within a few hours and resolve within one to two days. Common examples include:

• Soreness or swelling at the injection site: Your pet may be a little tender or hesitant to be touched in the area where the vaccine was given.

• Mild fatigue or lethargy: Pets may seem sleepier than usual for a day as their immune system responds to the vaccine.

• Slight decrease in appetite: Skipping a meal or eating less than usual for a short time is not uncommon.

• Low-grade fever: A mild fever may occur as your pet’s body builds immunity.

These mild reactions usually don’t require medical intervention. Allow your pet to rest and provide fresh water and comfort.

Less Common but Concerning Side Effects

While rare, some pets can experience stronger reactions. Contact your veterinarian if you notice any of the following:

• Persistent vomiting or diarrhea: Ongoing digestive issues after a vaccination are not typical.

• Facial swelling or hives: This may indicate an allergic reaction.

• Difficulty breathing or persistent coughing: Breathing changes should always be taken seriously.

• Severe lethargy lasting more than 48 hours: If your pet remains unusually weak or unresponsive, seek veterinary care.

• Large, painful swelling at the injection site: Some localized swelling is normal, but if it worsens or doesn’t improve, have it checked.

When to Call the Vet Immediately

Any signs of anaphylaxis (a severe allergic reaction) require immediate veterinary attention. These include:

• Collapse or fainting

• Pale gums

• Severe difficulty breathing

• Seizures

Though extremely rare, these reactions can happen within minutes to hours after a vaccine. Acting quickly could save your pet’s life.

Why Vaccines Are Still Essential

It’s important to remember that the risk of serious vaccine side effects is very low compared to the risk of your pet contracting dangerous, sometimes fatal, diseases. Vaccines are carefully tested for safety, and veterinarians follow strict guidelines to minimize risks.

Talk to Our Veterinary Team About Vaccines

Pet vaccines are a critical part of preventive care, keeping your furry companions safe from serious diseases. While most side effects are mild and temporary, knowing what to look for helps you act quickly if something more serious develops.

At Brekke Veterinary Clinic, your pet’s health and safety are our top priorities. If your pet is due for vaccines or if you have concerns about side effects, our team is here to help. Visit our office located on W Happy Canyon Rd. in Castle Rock, Colorado, or call (303) 474-4260 to book an appointment today.