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Avatar universal

Just Say NO To Convenia.. This is a dangerous drug...

Hello Everyone,

I was asked to post my information and video about Convenia here. This drug isn't safe due to how long it stays in the system alone. If your cat or dog has a bad reaction it will be very difficult to counteract that. I hope this will help someone avoid the death or harm of their beloved cat or dog. Please inform yourselves about Convenia if you're not familiar with and request that NO CONVENIA be put in the charts. Lets take this drug off the market for good..

My cat Angelina had a reaction to Convenia only 10 days before she passed away. I did a necropsy at Cornell Hospital Pathology Dept. They found that they think she had liver adenoma/ cholangiocarcinoma as well as acute myeloid leukemia. In spite of the fact that she had an end stage liver cancer, it seems, nothing to that effect showed up in her blood work until 4 days after the Convenia shot. At that point her AST was elevated but not tremendously and they thought she had an infection. 4 days after that she had become severely anemic, there was no sign of anemia in any of her blood work before this. She also had a 4 minute claw test, which means she took 4 minutes to stop bleeding.

The findings at Cornell said that they did not believe Convenia caused her anemia, not because it wasn't possible, but because Convenia hasn't been reported to cause anemia. This isn't true, read Dr. Pierson's website, read Pfizer's own foreign market results which state it has caused hemolytic anemia- I have also communicated with someone else whose cat developed hemolytic anemia and who passed away after 4 blood transfusions and I have read other accounts of anemic reactions. So this drug does cause anemia as well as many other severe effects.

When Angie received Convenia she had what seemed to be a cold which wasn't going away, she didn't seem gravely ill at that point. She had had some weight loss in July, but her blood work was normal. We did a thyroid panel in September which was fine. Then she had some hair loss for which I never found out the cause yet.

After Convenia, she developed a high fever, she became extremely doped, she was hiding in the closet and she stopped eating completely. Throughout this she kept seeming to revive as if her body was trying to fight off the reaction. She was given Orbax and her fever lowered and she ate three dishes of food, but then she regressed and started hiding again.. it was at this point I believe the anemia began... I had given her fluids at home and the next day when I brought her for an ultrasound of her abdomen, they thought from an xray that she had possible pancreatitis and had given her more meds for that, she had a large bruise at the site of the fluids.

That day her dvm told me she was severely anemic and she thought Angie was dying... the dvm was very upset- she was crying. I took Angie to a speciality hospital where she was given iv fluids, pain killers and tested. They told me that night they were considering Convenia as a cause of her anemia, I had just read all about it, not having been warned of any of the severe side effects, and I called them to tell them about that. I decided to take her home and try to treat both the cancer and the FeLV( see below) with steroids and other drugs, but I knew the next day she was in too much pain and I had to let her go.

Now that it has been determined that she had a non felv related cancer, as well as acute myeloid leukemia, which could or could not have been caused by FeLV, she had one inconclusive and one positive eliza test but no IFA test, which I was finally informed of the day she left the speciality hospital, I fear that both Pfizer and dvm societies will not believe that Convenia played a role in her death.

I still plan to file reports with Pfizer and with the FDA as well as warn everyone I can not to use Convenia. I will never use this drug again- I had already refused it once in July when Angie developed a cold after receiving two vaccinations. I had stopped vaccinating my cats due to health issues and I decided to do a rabies which I was still doing as well as a distemper. I think that was the trigger for her FeLV, assuming she really had this, because it stimulated her immune system too much. Angie was one of two kits of a feral queen  who was put to sleep in a shelter, I believe that she may have contracted felv from her mom and then fought it off, but the virus hid in her bone marrow to later resurface.

I had never heard of Convenia before that but I rejected it on the basis that it stays in the system too long. I will always regret giving her Convenia, but had I been warned about the severe side effects reported in foreign market studies I NEVER would have allowed it. I think it is crazy that DVM aren't required to warn us about all of this.   Please see my video Just Say NO to Convenia at youtube.

Please inform yourself because no one else is going to unless this drug is removed from the market, which is my goal. Don't risk the health and lives of your beloved fur babies. There are plenty of safe alternatives to Convenia. I would avoid Baytril also as I have read that it causes blindness and possibly other effects.

Please see my video "Just Say NO To Convenia"  linked below for further information on how to treat an adverse Convenia reaction- aggressive probiotic therapy has been used successfully.

Here is a list of adverse reactions reported in the foreign market study conducted by Pfizer: Please report all adverse events to Pfizer and to the FDA. 1-800-366-5288

FOREIGN MARKET EXPERIENCE: The following adverse events were reported voluntarily during post-approval use of the product in dogs and cats in foreign markets:
death, tremors/ataxia, seizures, anaphylaxis, acute pulmonary edema, facial edema, injection site reactions (alopecia, scabs, necrosis, and erythema), hemolytic anemia, salivation, pruritus, lethargy, vomiting, diarrhea, and inappetance.
For a copy of the Material Safety Data Sheet (MSDS) or to report a suspected adverse reaction call Pfizer Animal Health at 1-800-366-5288.

"High doses of Cefovecin sodium (Convenia) can cause nephrotoxicity, neurotoxicity, hepatitis, changes in the blood leukogram and thrombocytopenia." *This is from Pfizer or another drug promoter's own literature- unfortunately for some cats and dogs this happens with one NORMAL dose.

Occasionally, cephalosporins and NSAIDs have been associated with myelotoxicity, thereby creating a toxic neutropenia4. Other hematological reactions seen with cephalosporins include neutropenia, anemia, hypoprothrombinemia, thrombocytopenia, prolonged prothrombin time (PT) and partial thromboplastin time (PTT), platelet dysfunction and transient increases in serum aminotransferases.

150 Responses
874521 tn?1424120397
thanks for the post...will keep bumping it up to keep it current...I want everyone to read!!!
242912 tn?1402547092
Thank you so much!
Avatar universal
you're very welcome :)
This seriously makes me wonder what the correlation between this antibiodic and the natural histamine in both human and animal bodies is? As most of us have unfortunately experienced at one time or another, our pets and us have both had a massive allergic reaction to many medications, mostly antibiodics due to the way they are produced and what they are produced from. My first kitty had received a shot of a 'regular' antibiodic, this was years before Covenia came out, and within ten minutes he was foaming at the mouth, burning hot, could not stand up, was having convulsions, luckily I got him back to the vet and a Benadryl like push was immediately done. He recovered within minutes. This MAY not be the issue; I don't know, however it is worth thinking about. This is obviously a strong injection if it does indeed work for that long in the pets body. I have a cat, Peyton with mast cell tumor cancer, which is fed off the natural histamine in his body. Besides a year and a half of chemo, Benadryl is given as well-it does not affect pets as it does us, knocking us out asleep. Please always check w/your DVM for dosage for each pet, it goes by size/weight/etc. however I will never ever not have Benadryl (over the counter from your local drug store long tablets so they can be broken in half if need be) around the house for them, it could very well be what is needed to spare them the time to get them to the vet. God Bless the animals and those who love them.
874521 tn?1424120397
681148 tn?1437665191
If anyone ever suggests this drug to my current cat or any future cats, I will definitely tell them I don't want to use this drug.  It's kinder to put a cat to sleep in a hopeless case than to put a cat through all of that.
Avatar universal
My cat recently passed away just 10 days after receiving Convenia.
I read your article AFTER the vet administered this drug for rhinitis. I wish I read it sooner... I would have never allowed Convenia. The vet said they "have good luck with this drug", no counter indications, no side effects to worry about. My cat Cloud was 16 years old. He began coughing and sneezing in April, and when I saw blood droplets in the sneezing I tool him to the vet. He dad strong heart, the air was going to the lungs, his temperature was normal, but he lost weight. The vet suggested MRI thinking it is cancer. He recommended Convenia thinking there was an infection. I think, after many sleepless days and nights since then, that there was something in the cheep litter I buy usually from no-name supermarket No-Frills in Toronto. I noticed that all 3 of my cats were sneezing more frequently after the new box of litter. The other 2 cats got over it and I returned the product. Cloud was not so lucky. He probably did have an infection because he started to eat less and even passed on his favorite shrimp... After Convenia sneezing stopped in 48 hours, there was no running nose. My joy did not last. On the third day Cloud became lethargic, hardly ate. On the fourth day he did not eat or drink but secluded himself. I called the vet and laid on him everything I read about Convenia. He did not know that it stays in the system for 65 days, was unaware of Phizer's "foreign market experience" and stood by his diagnosis of co-morbidity. Cloud showed no signs of any disease, he was playful and active throughout his episode with coughing and sneezing. For sure he had an infection that interfered with his smell but it was not viral, my other cats are fine. Convenia killed Cloud. The name sais it all. It's the vet's delight. It is the source of self blame... Thank you for posting the truth about Convenia. I will now report adverse events to Pfizer and to the FDA

Remoreseful Alexander
874521 tn?1424120397
I am very sorry for your loss Alexander, thank you for sharing Clouds story with us....we all have to keep getting the word out there for everyone to be aware of.
We trust our Vet's and treatment of our babies thinking they are in the know, however like with any medication even the ones we humans are prescribed...we need to be vigilant and informed.

God bless little Cloud, may you RIP...knowing you were loved♥
Avatar universal
My cat, which I consider my child received one dose of Convenia yesterday afternon at 2pm. I had my husband go without me, since I was unable to. What a mistake that was. My husband never cared to ask what is the safest way of treating an abscess in the front leg. I would have asked the doctor to confirm what bacteria is he infected with, so the correct antibiotic, if needed, is given. So pissed!!! He was given the injection, then my husband was told to give Orbax; another type of antibiotic; I guess a double whammy. Why not just confirm infection with bloodwork and have the abscess lanced and drained? I would have paid the money. I will update you all. I will go to the media if my cat is affected in any way. And to know Convenia stays in the system for over 60 days????? My husband should have been warned.
874521 tn?1424120397
don't blame your husband dear, most Vets aren't aware or don't recognize there is an issue with convenia....takes tons of complaints before they wake up and listen.
I just hope your baby isn't one that reacts to this horrible medication, many are okay with it....so lets just keep our fingers crossed, keep a close watch on him especially for excessive lethargy, don't know if there is an antidote..but be sure and ask just in case...
good luck to your dear sweet baby...keep us posted....
Avatar universal
I can promise you this, opus88, if my cat comes out just fine, I still care about other cats out there. I will research and call multiple vets in my community. I will update everyone on how educated the vets are in South Florida. Right now, Blu is responding well. He is back to his usual self. He has not lost his appetite; he is going potty normally; no nausea. His abscess is 50% smaller now. I am still hoping the 64 days goes by fast since I heard Convenia stays in system that long. Thank you, opus88. P.S If one knows if a med stays in your system for over 30 days, then a doctor needs to make sure beforehand if cat will have a reaction. The pet owner should also be given other alternatives.
874521 tn?1424120397
good for you!!!!!!!!!!!!!!!
you are so very right, a pet owner should always be made aware of any negatives about any medication....always!!
so happy your boy is tolerating it well and is coming along so good.....great news:))
Avatar universal
My 12 year old female shepherd cross was given Convenia( one injection) for a small hot spot skin infection on her abdomen in Feb. 2013. I would have been satisfied with giving her oral Keflex for 7-10 days to treat this condition as she has been on this antibiotic before with no ill effects. However, the Vet treating my dog suggested "Convenia". One time injection and stays in the system for approximately 2 weeks according to the vet. Easy/ breezy according to the Vet. She had also had baseline blood work done and yearly vaccines completed with this visit as well.
Happily I went home with my dog thinking she is covered. Well, not more than 24 hours later, my dog was weak, stunned and could hardly walk. She did not appear to respond to the calling her name or to go outside. She fell off the second step of our deck and appeared very confused as to her environment. She also appeared very lethargic and no appetite.
Called our Vet(as I had trusted the care provided for many years) and said that I thought something was seriously wrong since the visit the day before. The Vet said that they were unsure what the sudden deterioration in condition could be from. Really???
Only thing new....Convenia. She almost died as her kidneys and liver values went through the roof. I was so upset that I had not asked more questions. Our dog had several hospital admissions, IV fluids and Cerenia to alleviate the nausea so she might start eating again. Then followed the associated weight loss. We were so frightened that we were going to lose her. and serious discusion that it might be best to euthanize her if she does not improve..once again..really????  I asked the Vet on numerous occasions during her related hospital stays that I thought that the  Convenia made her sick .  The research that I did about Convenia after my dog got sick in fact made me believe that the drug  made her ill. Many comments posted about the owners and their pets demonstrates that this Convenia  drug used is unsafe. Our Vet side stepped /avoided any discussion about the fact that the drug may in fact made our dog so sick she almost died. How does an animal have a chance when it stays in the system for up to 60 days and there is no way to reverse the effects of this drug. I am usually very stringent about my pets and any drugs/ treatments. This one time, I trusted my Vet to keep my dog safe and do no harm. The Vet's only response was "all drugs have potential side effects" and assured me it was safe and had good results when used in cats?????? I can thankfully say our dog survived this horrible ordeal and seems to be herself again.  To those who have lost your precious pets..my heartfelt thoughts are with you.
The lesson in all this... I will never blindly trust again. My dog almost died . Hope this helps someone out there.
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