Confused By Side Effects From Prozac

KatherineE

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On December 6th, we started our 8 year old female on Prozac to deal with some aggression toward a new kitten we adopted. She was prescribed 4mg daily by liquid. She weighed about 9.9 lbs when we started. She tolerated the drug okay. We noticed lethargy and some appetite loss. Nothing too dramatic. She was also more withdrawn and irritable. We were hopeful that these side effects would lessen over time.

On January 3rd, we went back to the vet for a recheck. The vet was pleased by the progress we were making with her aggression. He wanted to maintain the same dose despite a bit of weight loss. She now weighs 9.65 lbs.

Since we’ve returned from the vet, her appetite has decreased even more and she’s seemed even more out of it. At first, I thought it was just a post-vet reaction. She was particularly grumpy that day and the next. But the problems persist.

I would have expected some of these side effects to have lessened at the one month mark of treatment. I’d decreased her dose from 4 to 3.5/3 mg the last couple of days. She ate some wet and some dry food yesterday. But it took a lot of coaxing. Today, I’ve only been able to get s bit of wet in her. She refused to eat her regular wet food, but ate some Weruva that another of our cats (who passed in September) preferred. She’s shown no interest in her dry food or in her treats. It’s like she hit a wall of some kind.

Obviously I need to check back in with the vet, but I’m tempted to reduce her dose even more (to 2.5 mg) to see if that helps. Is that too drastic of a reduction? Should I just take a complete break for a couple of days and then start back up at a lower dose? I hate to give up entirely because it really has helped with her aggression and has given us some breathing room for behavioral modification with the new kitten.

Thanks for her help!
 

Kflowers

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You shouldn't just stop the Prozac, you'll need to ease her off of it. Some cats don't suffer from withdrawal, but some do. Here's a couple of article found on a quick google. VCA is a large chain of Vets. The second article is from them. Please read it.

Withdrawal From Prozac in a Cat

and this one about Prozac for cats in general in case you want to talk to your vet about it.

Fluoxetine
 

JamesCalifornia

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~ I have a few cats on Zoloft . Same family of medication but fewer side-effects. In humans Prozac often will cause appetite loss and insomnia .
If it were my cat I would skip the Prozac for a few days and start back on 1mg. Be observant and see how kitty responds.
From what I am hearing I don't like Prozac for cats. I would ask the veterinarian about Zoloft.
Good luck to you & kitty ... :hellocomputer:
 
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KatherineE

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Thanks for your replies. I did get her to eat some kibble. Not enough to relieve my concerns though. I’m going to further reduce her dose and, short of that improving her appetite and mood, return to the vet for a more complete work up to make sure nothing else is going on.
 
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KatherineE

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Just an update. We did not give our cat her Prozac dose today. At least not yet. She did eat a little overnight and has eaten sporadically today. It’s taken less coaxing. She did not urinate at all yesterday. She pooped and peed mid morning and has had at least one long drink of water. She is not a big drinker unfortunately. Her mood is somewhat more normal. She’s preferring foods right now that her novel to her, which underscores my feeling that the Prozac has made her very nauseous. She may have associated Herve normal food with feeling sick.

I do have a call into the vet, but at this point I’m inclined to give her a few days off the Prozac and then—if the vet agrees—to start back up at a lower dose (say 2mg versus 4). Otherwise, we’ll need to discuss other options to control her aggression.
 

war&wisdom

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Just an update. We did not give our cat her Prozac dose today. At least not yet. She did eat a little overnight and has eaten sporadically today. It’s taken less coaxing. She did not urinate at all yesterday. She pooped and peed mid morning and has had at least one long drink of water. She is not a big drinker unfortunately. Her mood is somewhat more normal. She’s preferring foods right now that her novel to her, which underscores my feeling that the Prozac has made her very nauseous. She may have associated Herve normal food with feeling sick.

I do have a call into the vet, but at this point I’m inclined to give her a few days off the Prozac and then—if the vet agrees—to start back up at a lower dose (say 2mg versus 4). Otherwise, we’ll need to discuss other options to control her aggression.
Don't just take her off Prozac cold turkey, even for a couple days. She could suffer withdrawal. That happens to humans too, by the way -- when I forget to take a dose of my SSRI, I do not enjoy the physical withdrawal symptoms one bit.
 
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KatherineE

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Thanks for your input. I’ve read elsewhere that for animals who have not been on it long term (8 weeks or longer) you need not worry about withdrawal, but I’m not sure what to believe. The vet wasn’t even confident that her condition was related to the Prozac (but I feel confident that it was). I’ll keep a close on her.
 

JamesCalifornia

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I’ve read elsewhere that for animals who have not been on it long term (8 weeks or longer) you need not worry about withdrawal, but I’m not sure what to believe.
~ Prozac has a very long half-life - unlike other SSRIs it stays in the system much longer when dose is stopped. Keeping kitty off for a few days and seeing her appetite return is wonderful to hear.
I don't think studies in animals using SSRIs have been done - it's mostly trial and error. If you like your veterinarian great. If it were me I would get a second opinion.
Best wishes ...
 

war&wisdom

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~ Prozac has a very long half-life - unlike other SSRIs it stays in the system much longer when dose is stopped. Keeping kitty off for a few days and seeing her appetite return is wonderful to hear.
I don't think studies in animals using SSRIs have been done - it's mostly trial and error. If you like your veterinarian great. If it were me I would get a second opinion.
Best wishes ...
I was on Prozac myself, and I could get eletric shocks and palpitations if I didn't take my meds for a day or two. Please be careful.
 

Catstina

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~ I have a few cats on Zoloft . Same family of medication but fewer side-effects. In humans Prozac often will cause appetite loss and insomnia .
If it were my cat I would skip the Prozac for a few days and start back on 1mg. Be observant and see how kitty responds.
From what I am hearing I don't like Prozac for cats. I would ask the veterinarian about Zoloft.
Good luck to you & kitty ... :hellocomputer:
~ I have a few cats on Zoloft . Same family of medication but fewer side-effects. In humans Prozac often will cause appetite loss and insomnia .
If it were my cat I would skip the Prozac for a few days and start back on 1mg. Be observant and see how kitty responds.
From what I am hearing I don't like Prozac for cats. I would ask the veterinarian about Zoloft.
Good luck to you & kitty ... :hellocomputer:
Hi there!

After reading you remark about your cats being on Zoloft, (a medication I take) and my vet putting my little William on Prozac (a medication I tried and didn’t like) I’m wondering why my vet put him on Prozac instead of Zoloft in the first place if, as you say, and I have, as a human of course, personally experienced. Anyway, I plan to call tomorrow and ask her if she’ll switch William to Zoloft. My main concern now is that since starting him on it his appetite has decreased significantly and at just under 9 lbs, he’s not a big guy to begin with. Just found it uplifting to see that you have had success with putting more than one cat on Zoloft. What were their issues? Williams is marking and peeing outside the littler boxes.
 

JamesCalifornia

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Hi there!

After reading you remark about your cats being on Zoloft, (a medication I take) and my vet putting my little William on Prozac (a medication I tried and didn’t like) I’m wondering why my vet put him on Prozac instead of Zoloft in the first place if, as you say, and I have, as a human of course, personally experienced. Anyway, I plan to call tomorrow and ask her if she’ll switch William to Zoloft. My main concern now is that since starting him on it his appetite has decreased significantly and at just under 9 lbs, he’s not a big guy to begin with. Just found it uplifting to see that you have had success with putting more than one cat on Zoloft. What were their issues? Williams is marking and peeing outside the littler boxes.
~ I would chop a tablet of Zoloft into appropriate dose for kitty and give it by mouth in a small gelatin capsule. Try every other day. Watch for improvement .
Good luck ...😽💕
 
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