Prozac for cats is a standard treatment for cats with anxiety disorders or specific inappropriate behaviors.
It can be very stressful to live with a cat that is anxious and aggressive. I know because I’ve lived with one!
My cat, Bella, suddenly become aggressive shortly after she turned two. She would act super cuddly and then try to claw your arm off.
She also began having “accidents” outside the litter box and just generally being a pain to live with.
After this went on for some time, I took her to the vet, who prescribed Prozac.
After a few months of messing with the dosage and waiting for the treatment to take effect, she was back to her usual, calm self!
So let’s take a look at what might be able to help.
Medication for Cats
If your cat is prescribed a new medication, it can be somewhat frightening and confusing.
We only want what is best for our feline friends, so it only makes sense to learn as much as we can about any medication they’re taking.
That’s why we’ve put together this article about Prozac for cats.
We’ll discuss side effects, effectiveness, and take a look at a few scientific studies to give you all the information you need about Prozac for cats.
What is Prozac for Cats?
Prozac for cats is commonly referred to as Fluoxetine, which is its scientific name.
It belongs to a group of drugs called selective serotonin reuptake inhibitors.
Serotonin is the “feel good” chemical; it makes you feel calm and affects your sleep cycle.
Prozac for cats increases the brain’s reaction to this chemical, causing your cat to feel calm.
Prozac is used for both cats and dogs and is prescribed to treat anything from aggression to inappropriate urination.
So, how useful is Prozac for cats in treating these behavioral problems?
Prozac for Cats Urinating
One of the most common uses of Prozac is to treat inappropriate urination in cats.
When a cat becomes anxious, it is not uncommon for them to urinate to “mark” their territory.
This is especially true if the cat is experiencing an environment change or if you have recently adopted a new pet.
One study found that Prozac was effective at stopping urine marking caused by stress.
The longer the treatment lasted, the more effective it was.
A break in the treatment caused the behavior to start up again, though subsequent treatment was still effective.
Prozac for Cats Aggression
Just like many humans, it is not uncommon for a cat to become aggressive when anxious or stressed.
After all, we all know what cats do when they’re backed into a corner.
Now, imagine what they would act like if they always felt like they were backed into a corner.
That’s feline aggression caused by stress.
In some cases, this stress can be reduced by training and by modifying your cat’s environment.
However, if the catalyst of the stress cannot be removed, like a new baby for example, or the changes do not fix the behavior, it might be time to introduce medication.
Prozac for cats is one such medication and might be suggested by your vet to stop the aggressive behavior.
Forms Available for Prozac for Cats
Prozac for cats comes in a number of forms.
There is liquid Prozac for cats, transdermal Prozac for cats, and oral Prozac for cats.
But, one study showed that a Prozac cream was less effectively absorbed by the cat’s system than oral Prozac.
Therefore, oral Prozac is the most common form. It is most effectively absorbed by your cat’s system, and it is the easiest to give.
Prozac Dosage for Cats
The dosage of Prozac for cats depends on what is being treated.
The dose of Prozac for cats is usually given every 24 hours.
You and your vet will probably have to adjust the dosage over a period of months, since every cat reacts to the medication differently.
Because of this, there is not a standard dosage for cats.
You should ask your vet if you forget which amount you are supposed to be giving to your feline.
How Long Does Prozac Take to Work in Cats
When you first begin giving your cat Prozac, it can take three to four weeks before you start to see any change.
Then, the change might be too extreme or too little. Odds are, you and your vet will have to adjust the dosage.
It is essential to stick with this medication even if it doesn’t appear to be working. Stopping suddenly can cause unpleasant side effects, such as worsening behavior.
Prozac for Cats Side Effects
Because Prozac affects the brain, a number of side effects can occur.
Serious side effects include seizures, tremors, shivering, muscle stiffness or twitching; a red, blistering, peeling skin rash; problems with balance or coordination; or agitation, confusion, sweating, or fast heartbeat.
Minor side effects include drowsiness, dizziness, weakness, runny nose, sore throat, nausea, diarrhea, changes in appetite, weight changes, and dry mouth.
One study found that Prozac for cats can also make it harder for cats to sleep deeply, so sleepiness is a widespread side effect.
Because of this, all medications that can cause drowsiness should be avoided while your cat is on Prozac.
Always report side effects to your veterinarian, as they might indicate a change of dosage is needed.
Prozac for Cats
Prozac for cats can be extremely useful in curbing stress-induced behaviors.
However, a vet prescription is required to give your cat this medication.
You should work closely with your vet when giving your cat Prozac to figure out the best dosage for her.
It is imperative to take your cat to the vet if they experience stress-induced behaviors.
These behaviors can be signs of an underlying problem or anxiety disorder. Medication can help.
References and Further Reading
Siegel, Jerome. “Serotonergic inhibition of amygdala-kindled seizures in cats.” Brain Research. 1979.
Hart, Benjamin. “Control of urine marking by use of long-term treatment with fluoxetine or clomipramine in cats.” Journal of the American Veterinary Medical Association. 2005.
Curtis, Terry. “Human-Directed Aggression in the Cat.” College of Veterinary Medicine. 2008.
Ciribassi, John. “Comparative bioavailability of fluoxetine after transdermal and oral administration to healthy cats.” American Journal of Veterinary Research. 2003.
Kaur, Gagendeep. “The use of fluoxetine by veterinarians in dogs and cats: a preliminary survey.” Veterinary Record Open. 2016.
Slater. “Inhibition of REM sleep by fluoxetine, a specific inhibitor of serotonin uptake.” Neuropharmacology. 1978.
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My cat is generally unmedicatible and considers the slighest thing to be punative and avoids me for days. I have a siamese who has bad anxiety of every type, and prozac clearly helps her except the only way I can give it to her is to rub the cream in her ear, which is enough of an ordeal. I do it once a week and I can see a big difference, but also she is so picky and will not eat unless it is junk, that I wonder if it is worth all this.
Try the oral tablet. Put a small piece of cheddar cheese about the the size of a small post it note (my cat prefers Sargento sharp cheddar sliced) and microwave it until its a melted slippery consistency (I do 7 seconds on high) and put the pill in it. Blow on it before giving it your cat because it will be hot. The key is to keep it a slippery consistently and it slides right down their mouth when they take it from you. Good luck
Try a higher dosage. Mine has to get double the typical dose. Also, a pill popper ordered from Amazon can be a lifesaver! It’s 2 sec of discomfort a day. I feed mine a lot of treats throughout the day (as well as immediately after he gets his pill) so he will be distracted and also so he will see my presence as something good —most of the time lol—in his life.
I had a cryptoid cat and live in a country with very limited vet services. We were not able to remove the undescended testicle until after he sexually matured. In fact I only did it because his spraying became so bad I was willing to risk it. After the surgery he started spraying again. He would spray anywhere and everywhere up to 8 times a day. I spent hundreds of dollars on products and was cleaning up after him 2 hours a day. I didn’t have the heart to put him outside or lock him in the garage but my life was becoming a nightmare. There was a neighbors cat outside that was irritating him but I couldn’t get rid of that one either. After 18 months of living with this constant urine smell, always closing rooms off and almost no relationship with my cat, I decided to start discussing putting him down. As a last ditch effort I put him on Prozac. It had n effect for six weeks and then a miracle happened. He started spraying less and then a few weeks later not at all. My kitty is back to being a little love bug. He still watches the neighbors cat but doesn’t mark. He had access to the whole house again. So far no side effects. I share this because it worked on a cat that had been spraying non stop for over a year. I didn’t think anything would work. If you have this problem you may want to try it. I can only get human Prozac capsules but I cut it down to 5mgs and mix it with paw gel. He eats it up everyday with no issue.
This gives me hope. I’m at week 5 and my cat is still spraying. I just don’t know what else to do if this doesn’t work. I’ve tried so many things. Maybe in another week I’ll see a difference. Fingers crossed
How is your kitty doing now? Did you have to raise the dose?
I read on another cat site that it may take a few months working with your vet to get the right dosage.
I just started my 9 yr old cat on Prozac – .4 ml of a 10mg/ml suspension. I opted for the liquid because I thought it would be easier to dose. It’s alright.
She started acting aggressive to our other cat when there hadn’t been a problem between them for the 2 yrs we’ve had the 2nd cat.
It became an anxious cycle culminating in 1st cat defecating all over the house, every day and peeing on my bed.
I took them both to the vet when 2nd cat was having tiny splats of pee in the litter box with blood in them.
Due to stress both had psychosomatic cystitis with 1st cat also having inflamed intestines.
For drugs, we came home with Buprenorphine, Dasuquin, fiber packets, Onsior & Metronidazole. Not all were given to both cats.
They also wanted my poor cats to eat Hills Diet c/d for urinary care. Well, I did my research a while back and have been feeding them premium brands manufactured by companies that believe cats are carnivores and don’t need to ingest pea products, tapioca starch, grains, rice, gums, legumes, etc.
Consequently,they refused to eat the Hills Diet mess which 2nd ingredient is corn, then corn gluten, wheat, brewer’s rice! That’ll sure make my cats feel better.
I’m glad to have a realistic idea of the time this might take. 1st cat is angry about having to have liquids squirted in her cheek.
Now I’m anxious about where she’ll poo next – on top of me sleeping on the couch?! She totally ruined our mattress.
CatMom, I would love to hear how your furball is fairing.
Hi there how os yout household doing. Mine is exactly the same. Pee on bed. We did however have a freak accident. 1ste cat fell from somewhere hit a hard surface with her jaw and broke off eye tooth. They operating the jaw and extraction on monday. We have spent money on every natural calming meds. Feliway, calm eeze l,homeopathic etcm the 1st cat is now on prozac. And shes still very much on edge. Its been a household out of hell. 2nd cat is very scared and timid. We were also asked to change to the hills food but we have 3rd 20 year old cat who also eat with them and shes on special joint/unirary food. Weve contacted an animal communicator.we dont even know if that will work.
Unfortunately, the Prozac stopped working after 3 months. The spraying started again. I put him on buspirone but that didn’t work either. I am supposed to move and I don’t see how I can take my fur baby to a new house and let him destroy that too. This is a very thought problem and he is going to be impossible to rehome. I am not sure what else to try.
I would like to hear how everyone else’s cat is doing or if anyone has any ideas.
Hi, my cat did not respond to 5 mg. He is now in 10 mg of Prozac, and the peeing and aggression have really almost ended (less than a month still). I strongly encourage you to increase the dosage. Every cat’s system is different. The only thing is that you’ll need to keep it up for several weeks before you necessarily begin to see the results. Good luck!
I had one beautiful cat that was spraying everywhere because of the feral cats outside. I took him to a vet who said nothing could be done. I even asked about prozac, but he said no. I put the cat I loved down because I couldn’t live like that. It was only years later that I found out that there was a solution.
I adapted a feral, but when I adopted the 2nd feral the first started spraying. I also took this cat to a vet and she prescribed 10 mg of prozac. It didn’t work so she raised the dose to 20 mg. That worked. The only worry I have is how to get it into him if I go on vacation. Any ideas? The cat won’t go close to anyone but me.
Try a higher dosage. Mine had to go up to 10 mg/day, but it is working — and 5 mg was not. Also, a pill popper ordered from Amazon can be a lifesaver! It’s 2 sec of discomfort a day. I feed mine a lot of treats throughout the day (as well as immediately after he gets his pill) so he will be distracted and also so he will see my presence as something good —most of the time lol—in his life.
Giving this a shot as well as I only have access to 40mg capsules I can break down. It’s cheap for humans but a bit costly for the cat variations. Thanks for your input.
Have your vet call 5 mg tabs (or 10) into Walmart. It will only cost you $4 for a months supply, and you won’t need to be bothered cutting them down to size. Good luck!
Just human Prozac? My kitty is on the cream one for the ears….. been on it for a month. Not sure it’s working?
Prozac has been a lifesaver for my six year old, neutered male cat.
Mani had a stressful start in life; in fact, when I met him, I was a vet tech and he had a fractured leg and had been surrendered by his owner. He was only eight months old.
Fast forward to after his orthopedic surgery, wearing a cast for six weeks (as well as an e-collar) and was now full time indoors, when his previous life was outdoors.
In very important ways, my new cat’s life had improved, but it was not without its stressors.
Anything negatively affecting mobility can be hard on a cat. Add to that a newly indoor lifestyle with three other cats and not even being able to jump up on a table, and maybe you can guess where this is heading.
A month after his cast came off, Mani developed a urinary blockage. It took a LOT of drugs to get him well. He did not need a urinary catheter. As soon as he was anesthetized, he passed a urinary plug.
No infection, but wow, the spasms. Thus began a series of intermiitent sick/well periods.
He never used my bed to pee on but sometimes he did use the sink. I wasn’t concerned about that, however; it was the pain and concerns over a future blockage.
Taking him to work (the clinic) made problems even worse. He would hold his urine all day, refusing to use the litter box there. I’d get him home and he would pee small amounts of blood.
By age four, he was having several bouts a year, and becoming more frequent.
Finally, my coworker (a vet) asked, “sowhen are you going to try Prozac?”
Mani wasn’t urinating inappropriately or marking. He was having spasms and inflammation.
I couldn’t really work it out in my mind how fluoxetine would help with Mani’s symptoms; nevertheless, there was nothing to lose.
This is where it gets amazing:
My cat did not need weeks to show improvement in his symptoms. He was able to to go off off three of his meds in a matter of a dew days.
That was almost 18 months ago, and Mani has not had another episode of pain, straining to pass urine, using the sink to relieve himself, or having blood in his urine.
I have been a veterinary technician for over 20 years and seeb a lot of things in my time. I never, however, would have believed a cat could have such a life-changing response to an antidepressant.
Fluoxetine has given this cat a life I wouldn’t have believed possible.
He gets 2 mg every other day in a treat. He is calm, playful, and loving, sleeping next to me every night.
I am not saying an SSRI will *fix* every cat, but for those who need the bump in their neurotransmitters, it can be helpful
In the case of Mani, I’d say fluoxetine has been a miracle drug.
I have a rescue cat- a THREE-time return from a no-kill shelter-because of his attacking humans. He was declawed when the shelter got him-who knows what his sad life had been. I have worked hard to earn his trust. He is not a cuddly cat, but always wants to be near me. But he has attacked my husband several times. When my husband is near, he meows angrily. After the last attack, my husband said we needed to try medication. Two weeks now of prozac-and now my cat avoids me, flinches or runs away when I pet him. No attacks-but my little guy is gone. Will he ever come back to normal, or is this what I will see for the next decade? ? Any advice on whether I will ever see him friendly again will be appreciated.
Evie, bless you for trying with this poor kitty. Who knows what he has been through? I hope the prozac has kicked in for you by now and you & your hubby have seen seen improvement with your kitty. If not, it is possible a different SSRI med would be more appropriate for your little guy.
Also, you MIGHT talk to your vet about adding a wee touch of Alprazolam (xanax) to kitty’s med regime if possible. (Mine takes hers easily in a Pill Pocket.) It causes a more immediate result and USUALLY, makes kitty a bit calmer and more friendly. Many times it is used in CAREFUL conjunction with prozac to give the prozac several weeks to start taking full effect.
Then the cat can be WEANED off the Alprazolam (pets should always be weaned off ANY of these drugs, never a hard stop) over the course of a couple weeks. Just a thought, perhaps to discuss with your vet. I hope things improve, not many people would take on a kitty with emotional issues. I have, and it’s a real commitment. Best wishes to you & yours.
do the side effects of this medication decrease at all? My cat has been on it for a week and recently started meowing for no reason. Any thoughts?
Thanks for this. I have 2 cats. The younger one, Emmy (3) has always had a ton more energy but 2 months ago started attacking Sally (5) after 2 years of peaceful coexistence. Sally started pooping outside the box due to the stress and I’ve had to isolated Emmy at night because of the stalking and attacking. They are both now on Prozac and I’m praying for a miracle. Emmy can be sweet and affectionate and I don’t want to rehome her. Thanks for the article. I’m so stressed out that I’m not sleeping because of the chaos but I’m committed to trying to make this work.