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    Death after Convenia shot
    An_251399 posted:
    We lost our 10 yr. old cat yesterday within 15 minutes after an injection of Convenia. We had taken him to the vet (second time in the past month) because he had not been eating much and was losing weight. The vet originally thought it was because we got a new cat a month ago and that he was stressed. A few days ago he quit using the litterbox and after a call to the vet they thought he might have a UTI. We took him in and he received 2 shots yesterday, one was a combination of vitamin B/penicillin/and a steroid of some kind to stimulate his appetite. The other was Convenia to cure the suspected UTI. We brought our cat home and he ate a fair amount, went to the litter box but just lay down in it. We got him out and he started acting really strange, he was howling and falling when he walked. He started having what may have been a seizure and his breathing became raspy. He died within minutes. This was all within 15 minutes of returning from the vet. The vet requested to do an autopsy to determine the cause of death. The report came back that all of his organs were healthy with no sign of any cancer, etc. We are just devastated as this is the second cat in 3 months that we have lost suddenly. (the other one was his litter mate who died suddenly of an apparent stroke) I have been doing some reading on Convenia and have learned that this is not the safest drug to use. The vet believes he died of something genetic or a toxin in his system but it is too much of a coincidence that this happened right after getting the shot. Has anyone else had a similar experience?
    Drew Weigner, DVM, ABVP responded:
    I'm so sorry for the loss of your cat. It does seem coincidental that he died so soon after his injections. There are three possibilities: that he was more ill than realized and died from his illness, that he reacted to the Convenia injection, or that he died from something in the other injection. While it's possible for any animal to have a reaction to any medication, Convenia does not seem to cause more reactions than others, and we have been using it without problems for years. Your veterinarian may have more insights into his cause of death.

    Drew Weigner, DVM, ABVP
    The Cat Doctor
    Board Certified in Feline Practice
    An_251399 replied to Drew Weigner, DVM, ABVP's response:
    Dr, Weigner: Thank you so much for your reply. We are still in shock over the sudden loss of our cat. We truly appreciate your advice and are waiting for a return call from our vet to discuss this further. We have ruled out everything but the injections he received as the cause of death. He was not 100% healthy when we took him in, but he was not dying either, and the autopsy proved that. This makes it all the harder to deal with the loss of our kitty. Thank you for your expert advice.
    Lola_Mtl9 responded:
    I'm sorry about the way that you lost your 10 yr. old cat.
    My 15 yr. cat, "Chester" died on Wednesday within 4 hours of receiving a Convenia injection.

    He had a bad rash on his ears for a few days but was otherwise, alert, active, with a good appetite.
    My vet prescribed Prednisolone for 15 days, and Theraderm cream for 10 days and gave him the Convenia shot.

    I brought him home and would have started the other meds that night but within half an hour he was salivating, wasn't moving, and wouldn't eat his supper (Never happens).

    Two hours later he seemed worse. Very groggy. i tested his ability to stand and he just fell over into an unnatural lying posture. I picked him up to comfort him and he cried/moaned as though he was in pain.

    After contacting the clinic i was told to bring him back and the attending Vet recommended euthanizing him because he was clearly suffering. Groggy, in pain, his temperature kept dropping. His fur felt so cold, i kept trying to warm him.
    i agreed. ... i knew he was dying and had to stop his suffering.

    There is NO question in my mind that the Convenia injection killed my cat. His physical response to it was as though he had been given Poison.

    I have since learned more about the danger of this drug.
    There is a lot online and you may find these pages helpful:

    Convenia: Worth the Risk? - Lisa A. Pierson, DVM

    My Chester ~ RIP sweet boy

    Falconk replied to Lola_Mtl9's response:
    Oh my gosh! I am so very sorry about the loss of Chester. What you are describing in his last moments are very similar to what happened with our cat only we didn't even make it back to the vet. He died at home within 15 minutes of getting the shot. The vet we saw that day was not our normal vet but when I talked to him 3 months after this happened he told me just what I knew he would. That he has given this shot thousands of times in his career and has never, ever had a problem. He said it was just out of the ordinary circumstances and bad luck that we lost our kitty. I just can't believe that after hearing from you and reading time after time the dangers of this drug. Again, my sincere sympathy to you in the loss of your friend. This is a wonderful photo of him and I know he was a sweet kitty. Take care.
    miggy7 replied to Drew Weigner, DVM, ABVP's response:
    Sorry Dr. Too many real world problems with this drug including my Westie who had a shot today because of a teeth cleaning and now is very withdrawn and moaning. My research has taken me to many websites with real world problems with this drug including death. I am devastated and very worried.

    Maybe a simple internet search would do you well. Start with the Facebook page and this link:

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