Benadryl and Cats Side Effects: One Ragdoll Cat Owner’s Nightmare

Ragdoll cat reacts to benadryl injectionOne Ragdoll Cat Owner’s Nightmare with a Benadryl Injection

Ragdoll cat George‘s parents thought that an injection of Benadryl would help alleviate any type of reaction to the rabies vaccine.  What happened next was a nightmare.

George’s mom, Joy, submitted the following story:

For: “George” Ragdoll DOB: 11/11/12

During George’s’ annual exam this year, our Vet stated that he was in “perfect health” It was time for George to receive his annual rabies vaccine. We are always leery of George getting a vaccine due to past issues of being very sensitive to any type of medication. Because of past issues, the Vet gave George an injection of Benadryl in his left hip, to alleviate any type of reaction that he may have to the Rabies vaccine.

Benadryl and Cats Side EffectsSeveral days past since the visit we noticed that George was not moving his bowels in a normal fashion. He had symptoms of constipation that included straining in the litter box, crying in the litter box and one episode of emesis. I called the Vet and was told to give George 1/8 to ¼ tsp. of Miralax twice a day. I was also told that I should continue with a daily dose of CATLAX. We assumed that the Benadryl had caused the constipation. Shortly after that, George did have a bowel movement, which eventually resolved, but another issue arose.

Later on that day on (a week after the Benadryl injection), I noticed that George was licking his left hip area more than normal when cleaning himself. Upon investigation, I discovered a hard circular area on his left hip that had a strong odor as well as some drainage. I had not noticed this earlier in the day during his daily brushing.

Suspecting an infection, a trip to the emergency Vet was necessary. The ER VET informed us that George had an abscess (6cm X 8cm) on his left hip that needed surgical attention. George had surgery to excise and debride the abscess resulting in 6 –7 sutures and a drain. George was treated with antibiotics, anti-inflammatory medication, pain medication, warm compresses and an E-Collar for 10 days. I am sure that everyone that has ever had to use an E-collar can appreciate the secondary problems that arise!

Obviously our regular Vet felt awful about this whole situation and offered to help. She did reach out to the manufacturer of the Benadryl and reported the adverse reaction. Unfortunately, it did not end here…George had diarrhea (probably from a late reaction to all the stress and antibiotics), and had to be seen again about a month after the surgery. He was treated with medication and more TLC, of course! George is doing much better, but we still keep a close eye on him and monitor for any changes.

Benadryl and Cats Side Effects 2
George today

I requested that this be posted so that other animal owners are aware of what MAY happen…. Again I am not insinuating that anyone avoids injections. Because we may never know what George reacted to, whether it was the Benadryl, the syringe, or the inactive ingredients, our Vet recommended that George avoid any type of injection in the future. This was very difficult, stressful, and costly for our entire family, and I would never want anyone to have to experience this if it could have been avoided! There are many pets that can tolerate Benadryl and other medications with no ill effects.

Respectfully submitted.

I would like to add – I have given Trigg and Murphy oral doses of Benadryl to reduce swelling in their paws after being stung by bees.  It reduced the swelling and their pain levels with no side effects.  So I would feel OK giving them oral Benadryl without hesitation again.

Have you had experience with Benadryl and side effects with your cats?

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Hi, I’m Jenny Dean, creator of Floppycats! Ever since my Aunt got the first Ragdoll cat in our family, I have loved the breed. Inspired by my childhood Ragdoll cat, Rags, I created Floppycats to connect, share and inspire other Ragdoll cat lovers around the world,

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  1. Teresa Reid says:

    Oh my gosh! What a horrible experience for all of you. Am so sorry you all have gone through all this. Poor George! Hope and pray that he continues to get better every day and will never have anything happen like this again. One of my kitties is very sensitive to injections of any kind and so she gets a benadryl before her annual shots, but they always give it orally in pill form.

    Think I dread taking them for their annual shots more than they do receiving them mainly because of fearing something adverse is going to happen like this. Also my fear of the rabies injections is because they are linked to sarcomas.

    Did they give the benedryl and rabies injections in two separate locations?

    Also am wondering after hearing that it caused such a massive abscess, if their standard practice is to use multi-dose vials instead of a single dose vial. Have always been really leary of these for humans as well as animals because after the outer cap is snapped off, the vial with it’s rubber diaphragm is left out in the open. Before the needle aspiration, the rubber is supposed to be wiped off with a bacteriostatic swab such as alcohol (practice varies from place to place). This reduces the possibility of contaminating the medication inside the bottle.

    Thank you so very much for taking the time and effort to let everyone know about George’s experience. So sorry and hoping that he makes a full recovery very soon with no residual problems. If you get a chance in the future, would love to hear how he is doing. Wishing George all the best.♥♥♥

    1. scottauto59 says:

      THANK YOU TO ALL OF YOU WHO COMMENTED AND SHARE THEIR LOVE AND CONCERN. SO APPRECIATED!! To clarify: YES a single dose vial was used and they follow universal precautions at my Vet. No worries there! George was given the Rabies in one hip and the Benadryl in the other hip. And for George, his days of getting ANY type of injection is over..this is JUST for him due to the severe reaction!! George is doing well now (Thanks again for your concern) IN fact, you will be seeing him soon (7/18/16) as RAGDOLL OF THE WEEK!!! THANKS AGAIN EVERYONE!!!

  2. I am very sorry to hear about what happened to poor George, but very relieved that he’s all right now! Thank you for sharing his story so others will be aware of such side effects. We have and have had many beloved kitties. Only one, Inspector Clouseau aka “Clue,” received a shot of some kind when he was stung on the tongue by a bee. It could’ve been Benadryl, but this happened about 20 years ago and I can’t be sure. Clue was fine afterward.

  3. I had a cat that had issues with his injections too. After that they gave him a pre-shot and about 10 minutes later, he’d get his booster shots of whatever he needed at the time. Thankfully, he never had a problem after that. They did not use Benadryl, but I don’t remember the name. I’ve long since thrown out his paperwork. I’m so sorry George (and family) had to go through this.

  4. Oh, no! Poor George and his family! What a horrible experience! I am so glad that he is okay today and doing well. What a nightmare (a very expensive nightmare, too!) this must have been for everyone!!! Thank you for sharing this very important story with us, Joy & Jenny!

    Personally, I have never had to use Benadryl on our Miss Pink Sugarbelle (she’s an indoor only kitty so her risk for allergens is minimal) and she’s never had a reaction to any vaccination. Whew!

    Thanks again for such great information that may help someone else in the future avoid this type of complication! <3

    Big hugs!

    Patti & Miss Pink Sugarbelle 🙂 <3

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