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How to Give a Cat Comfortis Flea Pills

Laura is an avid pet lover. She is an advocate for pet adoption and senior pets. She has multiple cats and a sweet old lady poodle mix.

A cat with fleas feels uncomfortable.  If you live in a warmer climate or if your cat goes in and out, you may have to work extra hard to fight them.

A cat with fleas feels uncomfortable. If you live in a warmer climate or if your cat goes in and out, you may have to work extra hard to fight them.

Comfortis for Cats

I have been fighting a flea problem with my indoor cats for several weeks.

All but one of my indoor cats seem to be responding to topicals such as Advantage or Frontline. However, they would still have a few fleas on them in the evening when I would comb them.

But that one cat was still having a flea party despite me trying two kinds of topicals and flea combing him every day.

I went in to talk to my vet's office and they recommended Comfortis (which I already give to my dog).

Here is my review of Comfortis and how to give your cat that large pill with relative ease.

The results of Comfortis make it worth the trouble.

Where to Get Comfortis for Cats

Comfortis is a 30-day pill that gets rid of fleas by killing the adults and breaking the flea cycle. It was approved in August 2012 for use in cats but word has been slow to get out.

You can only get Comfortis from an approved vet office, although some may offer an online prescription.

If your pet is up-to-date on his or her shots, you should have no problem getting the pill.

How Does It Work?

Comfortis is made from a chemical called spinosad, which actually originates in soil. Spinosad attacks the nervous system of the flea and then kills it. When a flea bites your cat, it gets a dose of the spinosad.

One of the ways it helps control fleas is by stopping the reproductive cycle. Adult fleas can't live long enough to reproduce.

Correct Dose For Cats

Some packaging only includes a dog's weight. Just find the pill size and correspond it with your cat's weight.

Cat WeightTablet Size

2 to 4 pounds

90 mg

4.1 to 6 pounds

140 mg

6.1 to 12 pounds

270 mg

12.1 to 24 pounds

560 mg

Over 24 pounds

Combine above pills to reach proper dosage to weight ratio.

Sometimes you need something extra to break the flea cycle.  Comfortis for cats might be the answer.

Sometimes you need something extra to break the flea cycle. Comfortis for cats might be the answer.

Ways to Give Your Cat Comfortis

Many cat owners are hesitant to give their cat Comfortis because of the size of the pill and because it is imperative that the pill is given with food.

I've found a simple solution to take care of both aspects.

How to Give a Cat ComfortisTroubleshooting

1. Get a few tablespoons of canned food and place in a bowl.

Make sure it is an easy-to-digest food.

2. Break the Comfortis into 2 or 4 pieces.

The pills are large if your cat is over 12 pounds. They might be able to swallow the smaller one if they are under 12 pounds.

3. Place the cat in your lap, on its back with the spine pressed against your stomach.

You can wrap the cat in a towel with only his or her head sticking out if they tend to fight being handled.

4. Give the cat some food by letting him or her lick it off your finger.

If the cat doesn't want to take it, simply put the food on your finger and wipe it on the roof of their mouth. He or she will be forced to eat it.

5. Give the cat a piece of the pill by either hiding it in their food or gently prying open their mouth and dropping it towards the back of their throat.

To open a stubborn cat's mouth, take your thumb and first finger and place one on either side of the mouth, at the jaw. Press gently to cause the jaw to unhinge then drop the pill as far back in the throat as possible.

6. Give all the pieces of the pill and then follow with the rest of the food.

Make sure to not overfeed the cat. The goal is to line the stomach and keep the cat from throwing up the pill. Guidelines recommend watching your cat for an hour to make sure he or she does not vomit. If they do puke after the hour, it is okay because the pill will already be absorbed. If they vomit before the hour is up, you may want to redose or try a different flea control.

Comfortis for Cats Can Be Used With Other Topicals

When you get Comfortis for your cat, it is important to talk to your vet about the possibility of using it with other medications your pet might be on. Since Comfortis just kills the adult fleas, I also wanted to be able to use a topical such as Frontline or Advantage in order to help inhibit the other life stages of the flea such as the egg and larva.

My vet said that it is safe to give a topical and Comfortis together because they work differently.

Since I am fighting fleas because of being in a southern state and because of the lack of a freezing winter, I have opted to continue topical use along with the Comfortis. Topicals were mostly working but needed that extra push. This pill was what I needed to achieve a flea-free pet once again.

You can buy Comfortis as a single dose, making it an economical choice if you are trying it out.

You can buy Comfortis as a single dose, making it an economical choice if you are trying it out.

Final Thoughts on Comfortis for Cats and Its Effectiveness

  • One of my cats was not responding well to topicals.
  • The vet said that some cats' skin and coat chemistry don't spread the flea medication as well.
  • I was afraid that Comfortis would make my cat sick when I gave it to him but it didn't.
  • Following the steps listed allowed me to ensure my cat took the pill with food, and none of the cats that I gave it to had an adverse reaction including a 14-year-old long-haired tabby.

If you seem to have super fleas or have tried topicals and they have failed, you might consider trying Comfortis, at least for a few months, in order to break the flea cycle.

A Vet Recommends Comfortis

References and Further Reading

This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.

Questions & Answers

Question: My cat does not eat chewables. Can I give the pill as a whole for them to swallow in a pill injecter. I see the effect of the treatment will be the same, even if the tablet is not chewed?

Answer: I have a fifteen-pound cat, and the Comfortis she takes is quite large. I break it into four pieces, wrap it in a bit of bread (a dough ball) and have her swallow it. Just make sure the piece is small enough for the cat to swallow.

Question: My cat has a flea allergy and Comfortis works, but she starts to scratch after just 25 days. Can I give another Comfortis flea pill before the full 30 days have passed?

Answer: No, you should not give Comfortis sooner. Sometimes Comfortis can be used in addition to other flea medications such as topical or a flea collar. I'd give your vet a call and see if there is an additional way to help get through flea season. (Example, see if the vet thinks it would be okay to apply a topical flea med on, say Day 15, every month, to help make the flea protection last until the cat's next Comfortis.)

Question: I currently have two cats. One is very large and the other is very small. As we all know Comfortis can be expensive. I’m trying to cut cost and would hate to purchase the small and large cat dosage. Is there ways to cut the pill to allow for a smaller dosage?

Answer: This could only be recommended by your vet office. Usually they understand that we all need to save money. I would talk to them and find out if there is a way to divide one pill for two cats. I would not recommend trying it on your own as one cat may get too much and one may not get enough.

Question: I gave my cats Comfortis three weeks ago. I’m going back to the store for flea collars. Can I put them on now, or should I wait until four weeks is up?

Answer: Generally, a topical flea medication is okay in addition to Comfortis. If you're unsure, give your vet a call and ask them if they are okay with you going ahead and using the flea collar.

© 2013 L C David


Melanie on February 15, 2020:

This website was very helpful; more so than the Comfortis website. I simply dropped the pill into my cat's food when he was super hungry first thing in the morning. He ate it no problem. I was surprised because it smells bad. He vomited about three hours later but otherwise did fine. I prefer this to the topical kind because he is a very flexible cat and always licked it off (he must be part owl). Also, we have a dog who licks him and kids who pet him.

Terry Skinner on October 01, 2018:

Can’t buy most reviews for comfortis. I smelled it as soon as I removed it from the package. Strong, strong mildew smell, first off. Second, the pill is so large, I had to grind it into a powder. Even when mixed into the strongest smelling food we could find, I could clearly smell the pill...and so could the cats. Refused to eat any of the food. Waste of 40 dollars

Larry L. Miller on May 19, 2018:

This cat with fleas is feral. Comes twice a day for food. I can't get it to a vet. It has scratched me good trying to hurry me up with its food. It has other problems but if I could just relieve its scratching it would be a giant leap forward.

Gina on March 09, 2018:

My fur babies trust their mama. It's not my favorite thing to do but found the best way to get my cats to take the pill. First, I give my cats a quarter can of food. I have a table just for them to keep food and water. The solid surface is a great platform to keep them steady. Gently hold the scuff of their neck and hold the pill between your index finger and thumb, running your finger along the side of their mouth to open (they do try clench their mouth shut) then quickly put the pill as far back into their mouth then gently rub the outside of their throat. It helps them to swallow. I give them a treat right after.

L C David (author) from Florida on February 18, 2018:

It would be wonderful if this was smaller and easier to dose.

Julie on February 13, 2018:

Our 2 cats ate the first dose, and have detected it the next 3 times, broken in pieces in their fav wet food then crushed and mixed in w/ sardine sauce. I'm not sure how much they're getting but they can smell the medicine, and will refuse after a few bites. Sardines are smelly! but they can smell the med.

This med needs to be made smaller and odor controlled. No good if need to restrain to give it.

L C David (author) from Florida on November 25, 2017:

It may be the fleas increasing movement as they are being affected by the medication. It should subside in a few hours.

Jane on November 20, 2017:

Is it normal for my cat to be scratching like mad after having the Comfortis tablet? It’s been over 4 hours and she seems to be terribly uncomfortable and can’t stop scratching.

Allan on November 18, 2017:

Some pills shouldn't be crushed because they need to slow release, otherwise your time and money is wasted.

L C David (author) from Florida on November 11, 2017:

I would think that this would be fine.

Shana on November 07, 2017:

Do u know if the tablet can be crushed? My cat had some difficulty chewing it an abandoned it after trying unsuccessfully a few times to bite into it. Can I crush it an add it to some tuna or something so he has an easier time taking it?

L C David (author) from Florida on September 22, 2017:

According to the Comfortis insert, the safety of its use in pregnant dogs and cats has not been evaluated. So it may be risky. I would give your vet a call and ask them for their recommendation.

Catherine on September 20, 2017:

Can I give comfortis to my pregnant cat?

O Swartz on May 01, 2017:

A very easy way for me to give my cat pills that doesn't involve stressing or restraining her is this: I crush the pill, mix it into a heaping spoonful of canned cat food and within 3 minutes the plate is licked clean so I know she has ingested it all. Her normal diet is dry cat food, (along with bits of whatever we're having for dinner ;-) so canned is a real treat for her.

D Scott on March 01, 2017:

Beef flavor, our cat's favorite. Just put it on plate with his dental treats and he ate it all.

Tobeylynn on February 23, 2017:

Omg. I wish Elanco would make the pills easier to give pets. I fight tooth and nail to get my dog to take her Trifexis and I just got Confortis for my indoor/outdoor kitty. He refused to eat it. I broke into several pieces and wrapped in lunchmeat. NOT easy, not gonna enjoy this every month.

L C David (author) from Florida on January 12, 2017:

Interesting idea. Thanks for the tip!

kg6ebj on January 05, 2017:

Use duck flavored soft dog training treats. I have found that mashing the pills (in my case 560MG) with 3-4 of the duck treats causes them to just scarf them down. Its a flavor that is intense, that is feral and that they don't get very often/at all any where else I got a bag for training/treats for my mom's ankle bitter but my 3 cats got to me first. They mobbed me the minute I tore the seal open begging for the new treats.

this is my first dosing with Comfortis and it hearties me to see that others are doing things similar to what I plan to do, half a pill in the evening, half a pill in the morning to give them the whole dose.

L C David (author) from Florida on December 27, 2016:

I agree. I hope that they are working on this!

MardiG on December 23, 2016:

It would seem the manufacturer should be able to make a smaller pill and one that is odorless. My cat can smell it a mile away and no amount of food masks it.

Beth on November 30, 2016:

That is a good idea!i also give my cat 1/4 of a 10 mg Pepcid an hr before her comfortis to help settle her stomach.

L C David (author) from Florida on October 23, 2016:

Comfortis is really amazing. But yes, sometimes tricking the cat is the best option. Some cats like the pill pockets (and see those as treats) so that might be another option.

Joan on October 07, 2016:

I delayed giving my cat Comfortis because of the size of the pill. She is about 5kg (11lb). A friend recommended squashing a quarter tablet into a small lump of cheddar cheese, and as she LOVES cheese, I tried that. It worked for two quarter tablets, then she spat it out. I had some left over chicken, which she also loves, so I gave her a couple of pieces, then squashed the other two pieces of Comfortis into some chicken, which I fed her by hand. She ate it with no trouble, and I gave her some food afterwards. She has had no side effects, and was already scratching a lot less the next morning.

L C David (author) from Florida on August 29, 2016:


I would assume that would work. Have you talked to your vet about her refusal to eat it? Is there something that she loves to eat?

kathy on August 29, 2016:

I have to grind the pill into powder and add it to her food. She will refuse to eat it - I leave it for several days sometimes. When I add the old mixture to new food - she is so hungry she will eat the whole mixture. My questions: will comfort still work as prescribed?

L C David (author) from Florida on August 13, 2016:

This is great advice!

L C David (author) from Florida on August 13, 2016:

You should follow the dosage-per-weight recommendation. It would depend on the size of the cat.

Lisa Loudermilk on July 15, 2016:

If you only give your cat half of the pill will it still help with the flees?

katie on July 02, 2016:

I've been using Comfortis for about a year after a bad flea infestation and the topicals just weren't working. We haven't had any more fleas! The first time, the cat took it like a treat. We didn't have to trick him or anything. The second and third time, it took a pill pocket to disguise the pill. The fourth time, he absolutely refused, so I took him to the vet. Now, I take him to the vet every month to get his pill. They don't charge to administer it!

It's tough because he has to take it with food, so as soon as we get back from the vet, I feed him. I try to get morning appointments and don't feed him until after so that he's hungry. One time, he threw up about an hour after getting the pill. To keep him from throwing up for the first hour, I spend an hour petting him and playing with him so he's distracted if he starts getting nauseous. The manufacturer's directions say that he needs a re-dose if he throws up within an hour, so I figure it's safe after an hour. So far, following the cat around for an hour has worked to keep him from throwing up!

romaneo789 on June 08, 2016:

I don't know if I tricked my cat by giving her a bunch of crunchy treats before and after, not to mention she eats mostly dry food, but I just offered her the pill and she ate it like it was a treat... They are labeled chew-able right? Has anyone else tried this?

L C David (author) from Florida on May 12, 2016:

You are likely infested somewhere in the bedding or living area where the cat lives. If it is outside, you may want to call a pest control company to come treat the yard. If inside you can do the same. Also, wash all bedding and vacuum daily. Keep using flea medication. Flea eggs can last many months so it may take some time to finally get the last of the live flea eggs hatched and killed. Hang in there!

rusty on May 08, 2016:

Cant get rid of fleas.....comfortis twice. Nothing works?

gators2film on December 07, 2015:

My 12 lb Cat has flea allergy,I've tried everything from shots and Advantix. Changed Vets,and He put him on Comfortis about a year ago and my boy has had NO problems since. Its hard to give it to him,so I just take him to my Vet monthly and they give it to him and only charge for the pill. Great Vet and great product

jed on October 15, 2015:

I give my cat comfortis once a month as she murders everyday and tends to scat her ears all the time. I have found the long meat treat sticks fabulous, all you need to do is give her a piece to get her juices going and then break the tablet into 4 pieces and put in a piece of the treat meat stick. This is quite flexible so you can squish it around the pill and she eats every bit, every time. Try it , it definately works.

Liz Elias from Oakley, CA on May 29, 2015:

I have been accidentally bitten by trying to drop in a pill after prying open a cats mouth, as they fight it. They are not trying to bite you on purpose; they are just making chomping motions trying to spit out the pill.

You can get a "piller" or "pill gun" from the vet that will put the pill far enough back in the mouth while keeping your fingers out of range.

Voted up.

L C David (author) from Florida on May 29, 2015:

Yes. The fleas get active as they are dying.

YSal on May 29, 2015:

My cat started scratching like crazy as soon as the fleas were dying. Is that normal?

L C David (author) from Florida on September 11, 2014:

I think it should be fine. I would sometimes break it up and put it in pill pockets so it should digest. Hope it works!

JAX in PA on September 11, 2014:

He didn't give me a problem at all while swallowing it it just effective??? Please let me know

JAX on September 11, 2014:

Can you just put in in their mouth without him chewing it??

L C David (author) from Florida on July 29, 2013:

Another way to get the pill down is to give them part of it, give them some food, give them a bit more and so on. Especially if they are a larger cat and need a bigger pill. I just gave my biggest cat his monthly Comfortis. Now he's pouting behind my desk. :-/

L C David (author) from Florida on July 27, 2013:

I really like this idea. The only concern I would have is if they still get full strength protection. I'll ask my vet next time I talk to her.

glh on July 22, 2013:

I have a 12 pound cat. The first time I gave him the Comfortis pill, he threw it up within about an hour. I waited two months and tried again. This time I split the pill into 4 pieces. I gave him 1/4 of the pill on 4 successive days. It seem to work. No more getting sick and fleas don't seem to be a problem. Live in FL which has had mild winters lately so fleas have been really bad the past two years.

dj6ta on June 10, 2013:

You are very welcome. I can imagine this would work for many other pills as well. I would caution though, some pills may have a coating on the outside that isn't all that water-soluable.

L C David (author) from Florida on June 09, 2013:

Thank you so much for sharing this. I'm keeping your ideas for use with my own cats. That would work great for a variety of pills!

DJ6ta on June 09, 2013:

I gave them their food earlier and I gave them food immediately afterwards so they can get that terrible taste our of their mouths. Yep, 30 pound cat, he is a big boy but is also the biggest cuddle bug I have ever seen, lol. Comfortis is really good stuff, I tried every topical treatment I could think of and nothing ever worked good enough to keep the tape worms away. I used Comfortis for my pitbulls way before it was OK for cat use, but even then I could see that this was going to be the best flea solution.

L C David (author) from Florida on June 08, 2013:

That's another fantastic way to do this. Do you give them food first? I found that my cats had to have some food first or they would puke it back up.

Wow. A 30 pound cat is quite a big one!

Comfortis really is good stuff! We had really bad fleas and they are all gone!

DJ6ta on June 08, 2013:

I have been doing the Comfortis pill thing with my cats for about a year now and it is murder to my arms every time. However, I just found the best way to do this. I start by trimming the claws, then, after that trauma has had about 10 minutes to wear off, I begin to crush the pill into powder form. The dust is very water-soluble so it mixes well if added into a medication syringe. I then add some juice from some canned cat food with the water and crushed pill inside the syringe. I bundle the cat in a blanket up to the neck and give the medication a few squirts at a time until it’s all gone. Despite the prep time, this process is a lot faster and it is less violent to the cats and to me. I then let them share the canned food I opened up earlier and they are set for another month. I hope this helps anyone who has a 30-pound cat like me and has to give them one of those horse pill sized Comforis doses.