Anesthesia Allergies in Cats

Anesthesia allergic reactions occur almost immediately following the cat’s exposure to anesthesia, which means your cat will already be in the presence of a doctor when symptoms begin to show. Although hearing your cat suffered a complication during a medical procedure is unsettling, as long as the vet was monitoring your cat and treated the reaction quickly, your cat should fully recover.

If your cat is going to the vet for a procedure that requires the use of anesthesia, it’s normal to feel nervous. There are many risks associated with anesthesia, especially if your cat has certain health conditions or allergies. Unfortunately, you can’t tell if your cat has an anesthesia allergy until he has already had a reaction. Cats can be allergic to local or general anesthetics, and symptoms may vary depending on the severity of the allergy. Some cats will only experience a bit of swelling and irritation where the anesthesia was injected or applied topically, while others will begin to go into anaphylactic shock or cardiac arrest.

If your cat is ever given local or general anesthetics during a medical procedure, the vet and his team of assistants will be closely monitoring him to look for signs of an allergic reaction, along with other complications. Some of the symptoms they are looking for can include:

• A drop in blood pressure
• Signs of cardiac arrest
• Swelling or irritation at the injection site
• Anaphylactic shock

Some cats will have an allergic reaction to anesthesia, while others will not. Unfortunately, there are no known causes of allergies. Allergy tests can be conducted to determine if your cat reacts to any common allergens, however, anesthesia is not one of the allergens included in testing. Cat owners do not become aware of their cat’s anesthesia allergy until the cat has already had a reaction. 

If your cat has a surgery scheduled in the near future, you will most likely have to bring him in for pre-op testing to ensure he is healthy enough to undergo surgery. You may be wondering why an allergic reaction can still occur during the procedure if your cat has been thoroughly pre-tested. This is because there’s no way for a vet to test for an anesthesia allergy. 

Prior to a surgery, you should let your vet know whether your cat has any known allergies and if he has ever had any bad reactions to medications in the past. If your cat has been given anesthesia before and had a negative reaction to it, your vet needs to know this before the procedure is performed.

Once a local or general anesthesia has been administered to your cat, the vet should immediately be able to diagnose an allergic reaction based on the observable symptoms. Make sure you ask your vet for the exact name of the anesthesia that was used so you know to avoid this type moving forward.

Luckily, anesthesia allergic reactions occur immediately, so your cat will already be in the presence of a veterinarian when the symptoms begin. The treatment will depend on the severity of the reaction. If it’s just mild skin irritation, the vet may not administer any medication unless the condition worsens. Moderate allergic reactions can be treated with antihistamines, which can be given orally or intravenously. If the cat is under sedation from generation anesthesia, the antihistamine will be given through an IV, however, if the cat is awake and reacted to local anesthesia, the medication may be given orally.

Serious reactions will need other forms of treatment. The vet may administer epinephrine through an auto-injector device such as an Epi-Pen. Epinephrine will immediately enter the cat’s system and begin to alleviate the symptoms associated with an allergic reaction. If your cat’s airways begin to swell because of the allergic reaction, he may be unable to breathe. The vet will need to closely monitor his airways during an allergic reaction, and if swelling is spotted, emergency surgery may be needed to open the airways.

As long as the vet is closely monitoring your cat while under anesthesia, your cat should fully recover from any allergic reaction that occurs. You should be able to take your cat home after his condition has stabilized. Make sure you follow all of the vet’s instructions closely and administer any corticosteroids or antihistamines as instructed. If your cat’s condition worsens, take him to a veterinarian as soon as possible.

Find out what type of anesthesia caused the reaction and ask your vet to write a note on your cat’s record so this allergy is documented. This will help you ensure your cat is not ever given this type of anesthesia again in the future.