They're beef-flavored, chewable tablets you give to your dog or cat to kill fleas and prevent flea infestations for one month. Comfortis chewable tablets are recommended for monthly use in cats 14 weeks of age or older and 4.1 lbs of body weight or greater and in dogs 14 weeks of age or older and 5 lbs of body weight or greater.
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Comfortis for Dogs 60-120 lbs (Brown) - 1 Chew Tab - [Fleas]
Item# HA21251525S
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- Description
- Ingredients
- Directions
- FAQ
- Reviews
Notices
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Description
Comfortis is the first FDA-approved, prescription oral flea treatment that provides fast-acting, month-long protection for both dogs and cats. This convenient beef-flavored chewable tablet (made with pork protein and hydrolyzed soy) starts killing fleas in just 30 minutes and eliminates infestations before they can start. Comfortis requires a prescription from your veterinarian.
Key Benefits
- Fast-acting flea protection – Begins killing fleas within 30 minutes of administration
- Monthly dosing – One chew protects your pet for a full 30 days
- Breaks the flea life cycle – Kills fleas before they can lay eggs and reproduce
- Convenient chewable tablet – Beef-flavored and easy to administer with food
- Environmentally responsible – Contains spinosad, a naturally derived insecticide
Indications
Comfortis (spinosad) is indicated for the prevention and treatment of flea infestations (Ctenocephalides felis) for one month on:
- Cats and kittens 14 weeks of age or older and weighing 4.1 pounds or more
- Dogs and puppies 14 weeks of age or older and weighing 5.0 pounds or more
How to Use
Comfortis should be administered once monthly with food for maximum effectiveness. Follow your veterinarian’s instructions for proper dosage and usage schedule.
Ingredients
| Comfortis for Dogs: 5-10 lbs - Comfortis for Cats: 4.1-6 lbs | |
|---|---|
| Active Ingredient (per tablet) | Amount |
| Spinosad | 140 mg |
| Comfortis for Dogs 10.1-20 lbs - Comfortis for Cats: 6.1-12 lbs | |
| Active Ingredient (per tablet) | Amount |
| Spinosad | 270 mg |
| Comfortis for Dogs 20.1-40 lbs - Comfortis for Cats: 12.1-24 lbs | |
| Active Ingredient (per tablet) | Amount |
| Spinosad | 560 mg |
| Comfortis for Dogs 40.1-60 lbs | |
| Active Ingredient (per tablet) | Amount |
| Spinosad | 810 mg |
| Comfortis for Dogs 60.1-120 lb | |
| Active Ingredient (per tablet) | Amount |
| Spinosad | 1,620 mg |
Directions
Comfortis is a prescription-only, chewable flea tablet formulated with the active ingredient spinosad. It provides fast-acting, monthly protection for dogs and cats and should be administered with food for best results.
📄 View Comfortis Drug Facts Sheet (FDA PDF)
Dosage for Dogs
Minimum recommended dose: 13.5 mg/lb (30 mg/kg) of body weight, administered orally once per month.
Important: Do not use the dog dosage chart when dosing cats, as it may result in underdosing.
*Dogs over 120 lb should be administered the appropriate combination of tablet strengths. Comfortis is best administered with food. If vomiting occurs within 1 hour of dosing, repeat with a full dose.
Comfortis can be offered as a treat before feeding, mixed with food, or administered like a traditional tablet. If a dose is missed, resume monthly dosing with food as soon as possible.
Flea Prevention Strategy: Begin Comfortis at least one month before flea season starts and continue monthly through the end of flea season. In regions where fleas are present year-round, monthly treatment should be maintained continuously. All pets in the household should be treated with a vet-approved flea control product.
Dosage for Cats
Minimum recommended dose: 22.5 mg/lb (50 mg/kg) of body weight, administered orally once per month.
Important: Do not use the dog dosage chart for cats, as it may result in an overdose.
*Cats over 24 lb should be administered the appropriate combination of tablet strengths.
Comfortis should be given with food. It may be offered before or after feeding, mixed in food, or administered as a chewable tablet. If vomiting occurs within 1 hour of dosing, redose with a full dose. Resume regular monthly treatment if a dose is missed.
Treatment should begin before flea season and continue monthly through the end. In flea-prone areas, maintain year-round treatment. All pets in the home should receive approved flea control to prevent reinfestation.
Contraindications
No known contraindications are associated with Comfortis use.
Warnings
- Not for human use. Keep out of reach of children.
- Serious adverse reactions have been reported when Comfortis was used with extra-label doses of ivermectin.
Precautions
- For use in dogs and puppies 14 weeks and older (see veterinarian for animal safety guidance).
- Use caution in breeding females and dogs with pre-existing epilepsy.
- The safety of Comfortis has not been evaluated in breeding males, or in breeding, pregnant, or lactating cats.
- Concomitant extra-label use of ivermectin should be avoided unless directed by a veterinarian.
Storage Instructions
Store at controlled room temperature: 20–25°C (68–77°F), with excursions permitted between 15–30°C (59–86°F).
Effectiveness
In laboratory studies, Comfortis began killing fleas within 30 minutes and achieved 100% effectiveness within 4 hours. It kills fleas before they lay eggs, helping prevent infestations.
Field studies over 3 months demonstrated 98–99.8% flea reduction in infested households. Dogs with flea allergy dermatitis showed visible improvement in symptoms like itching, redness, and hair loss.
FAQ
Spinosad is the active ingredient in Comfortis. It belongs to a class of antiparasitics known as spinosyns, which are derived from a naturally-occurring soil microbe. It works by attacking the nervous system of insects, causing the rapid death of adult fleas.
Treatment can begin at any time of the year. Comfortis is most effective when given one month before fleas become active, with continued monthly dosing through the end of the flea season. In areas where fleas are common year-round, monthly treatment with Comfortis chewable tablets should continue through the entire year without interruption. To minimize the likelihood of flea re-infestation, simultaneously treat all animals in your household with an approved flea protection product. Consult your veterinarian for the flea treatment options most appropriate for your area. See also, what should I discuss with my veterinarian regarding Comfortis for my dog or cat?
Spinosad, the active ingredient in Comfortis, began killing fleas in 30 minutes and killed 100% of fleas on dogs and 98% of fleas on cats in just four hours in controlled laboratory studies. Comfortis chewable tablets kill fleas before they can lay eggs.
Comfortis has demonstrated full effectiveness for an entire month.
Comfortis has demonstrated to be safe in healthy dogs and cats when used according to label directions. Use only for cats and kittens 14 weeks of age or older and 4.1 lbs of body weight or greater, and for dogs and puppies 14 weeks of age and older and 5.0 lbs of body weight or greater. The safe use of Comfortis in breeding, pregnant or lactating cats and dogs has not been evaluated.
Comfortis contains beef flavoring made from a pork-based protein. If your pet has an allergy to pork, you may need to consider an alternative for flea treatment and prevention. Please discuss these options with your pet's veterinarian. The use of ivermectin at higher than FDA-approved doses at the same time as Comfortis can result in serious side effects.
Comfortis kills fleas before they can lay eggs when used monthly, according to the label directions. If you see fleas on your dog or cat within a month after your pet receives Comfortis, they are most likely new fleas. Because your pet has been treated with Comfortis, these new fleas will be killed before they can produce eggs that contaminate your home. Continued monthly use of Comfortis can prevent any new flea infestations.
Your pet can experience continued exposure to fleas living in the environment. It's important to treat all animals in the household with an approved flea product to help control the flea population. Learn more about controlling flea infestations in your home.
As with any medication, sometimes side effects occur. See the Comfortis label for complete safety information.
For cats: In some cases, cats vomited after receiving Comfortis. If vomiting occurs within one hour of administration, re-dose with another full dose. Additional adverse reactions observed in studies were lethargy, decreased appetite, weight loss, and diarrhea. Use with caution with concomitant extra-label use of ivermectin. See the Comfortis label for complete safety information.
For dogs: The most common adverse reaction reported is vomiting. Other adverse reactions reported in decreasing order of frequency are depression/lethargy, decreased appetite, incoordination, diarrhea, itching, trembling, excessive salivation and seizures. Following concomitant extra-label use of ivermectin with Comfortis, some dogs have experienced the following clinical signs: trembling/twitching, salivation/drooling, seizures, ataxia, mydriasis, blindness, and disorientation. See the Comfortis label for complete safety information.
Administer Comfortis with food for maximum effectiveness. Because Comfortis is a flavored tablet, it can be offered just prior to or just after feeding. You can also administer Comfortis as you would other tablet medications. Visit the Dosing & Administration page for more details, or download the Comfortis label. Each box includes reminder stickers for your calendar to help remind you to administer each dose. You can also sign up for monthly text or email reminders.
In field trials, dog and cat owners were instructed to give the Comfortis tablet with food. However, the quantity of food was not specified and Comfortis was still effective. An option is to give Comfortis immediately before a regularly scheduled meal. For free feeders (dogs or cats who nibble throughout the day), you might take food away at night, administer Comfortis first thing in the morning, then put the food back down.
Give your pet his or her regular dose immediately, then resume a regular monthly schedule. To help you remember to dose your pet, sign up for monthly email or text message reminders. For complete safety information, view the Comfortis label.
Contact your veterinarian if you believe your pet has ingested more than the recommended dose of Comfortis. Visit the Dosing & Administration page for more details, or see the Comfortis label for complete safety information.
No. You can continue normal activities and interactions with your pet.
Comfortis is not contraindicated for use with any veterinary drug/product when they are administered at labeled doses. However, while labeled heartworm preventatives are not an issue, you should not use Comfortis concurrently with extra-label doses of ivermectin in dogs and should use caution in cats. Make sure your veterinarian is aware of all products that you intend to administer to your pet. In well-controlled field studies, Comfortis chewable tablets were administered safely in conjunction with other frequently used labeled products, such as vaccines, anthelmintics, antiparasitics, antibiotics, steroids, tick control products, anesthetics, NSAIDs, antihistamines, alternative/herbal remedies, shampoos, prescription diets, and most generally prescribed medications.
Your veterinarian is your pet's healthcare expert and can make the best medication recommendations. This includes the prevention, control and/or treatment of parasites such as fleas, heartworms and intestinal parasites. These parasites can cause conditions including flea allergy dermatitis, anemia, and heart disease. Key points of your discussion might include:
- The best time to start flea treatment in your geographic region.
- What administration method will work best for your pet.
- What to do if you miss a dose of Comfortis.
- What other medications you give your pet.
- What to do about a severe flea infestation.
- What steps you can take to prevent a flea re-infestation in your home.
Reviews
Review Summary
4.6
34 Reviews
5
79% (27)
4
12% (4)
3
3% (1)
2
0% (0)
1
6% (2)
94% Recommend this product (32 of 34 responses)
By Priscilla
Oregon
Got what I needed at a great price.
April 7, 2025
Got what I needed at a great price.
By Marie
North Carolina
WORKS
June 23, 2024
When my vets stop carrying Comfortis. I tried different ones nothing beats Comfortis.
Pros
- It works
Cons
- I cannot think of one
By irina
miami, FL
it really works
April 14, 2024
hi i have used comfortis for my cats since years- it is the best ,fastest flea medication on the market. entirely pets has the best prices
By Robin
ROSELAND, LA
All I ever use
March 26, 2024
Have been using this med for years for my inside dogs and my farm dogs. Love it
By Jaynie
Brunswick, GA
Comfortis is the best for my pets!
November 16, 2023
Nothing else works like Comfortis. No side effects, but I always give it on a full stomach. The fleas are dying in 30 minutes. Being able to purchase it in smaller quantities than the full 6 pack is a tremendous help due to the expense of the 6 pack. Thank you, EntirelyPets Pharmacy!
Pros
- Extremely effective. Fleas start dying in 30 minutes. Since it's given orally, there is no wet spot on the fur.
Cons
- Price, but being able to purchase 3 instead of the full 6 pack is greatly appreciated.
By Vicky
Spartanburg
Piece of trash
October 12, 2023
It’s not working at all, don’t waste your money on it…
Pros
- Nothing
Cons
- Don
By Elizabeth G.
Atlanta, Georgia
Easy Peasy
September 20, 2023
It's easier to give my long-haired cat a tablet than it is to try and put liquid meds on his skin!
By Patricia K.
Harvey, LA
Great Company to work with
September 18, 2023
After my order was confirmed with my vet. they shipped my dogs prescription meds same day and provided a tracking number so I knew when they were going to arrive.
By Mobile
Orlando
Confortis for Dogs
November 22, 2021
Works great.
Pros
- No problem with fleas
By Kathy
North Carolina
Comfort for our 2 Cats
July 31, 2021
This medication makes a big difference to our 2 cats. We live in the country (in a renovated tobacco barn) so flea protection is important. Our girls are much happier and more relaxed because of it. It works quickly, too.
Pros
- Works quickly. Our 2 cats have no adverse reactions from it. Amount given is determined by weight of animal.
Cons
- None.
By Lynda
Princeton, TX
Comfortis
June 24, 2021
I was hoping it was a chewable instead of a hard pill
Cons
- Hard pill. Hard to give to a cat
By Sandy
Virginia
Does the job
August 21, 2020
Works great. No more fleas! I have been using for about four months, killed the fleas and have not seen any more.
By Barbara
Jacksonville Al
Very satisfied
May 1, 2020
Love the product and the timely delivery
By Valerie J.
Massachusetts
Awesome
April 30, 2020
Thank you for getting the order right! The gentleman I spoke with was awesome.
Pros
- Thank you for getting the order right! The gentleman I spoke with was awesome.
By Kristi
Florida
The only flea and tick prevention that works!
March 15, 2020
I have tried all the other prevention such as frontline, etc and they were a huge waste of money! comfortis is the only prevention that has worked for all of our cats and dogs.
Pros
- Comfortis is worth the money because it actually works.
By HBGary
Huntington Beach
Two dogs, no fleas
November 17, 2019
We have used Comfortis for many years since our vet recommended it during a time of major flea infestation in the area and our dog was suffering (as we were too), Our current two dogs have always used Comfortis after the good experience we had with our prior dogs.
Merchant Response:Flea-free is the way to be. Comfortis is pricy, but worth it in the long run. Take care Gary.
Pros
- Easy to administer product to the dogs.
Cons
- Pricey
By Irene
Los Angeles, ca
Customer service
March 22, 2019
This review is for entirely pets pharmacy: great customer service! Wouldn't use any other online pet pharmacy
By ronald c.
1425 second ave Chula Vista, CA 91911
comfortis
February 8, 2019
I received product in a timely manner; so I'm well pleased! Thank you
By karla` s.
Miami, Florida
Works great
October 19, 2018
Always kills fleas within 30 minutes. Service was great and delivery on time.
By Katrina
Oregon Coast
Good Value
October 17, 2018
Easiest way to buy and a great price.
By Lu H.
Fresno
Recent order
August 29, 2018
First time using - great service - contacted my vet for a prescription right away and product arrived very soon after - will use again.
By spex
fountain valley , Ca.
I got it !
May 18, 2018
it was a little faster receiving the comfortis, and sale price was a bonus. I was pleased all around. It is easier to administer to my pet.
Pros
- Easier to give to my pet.
By KJ
San Diego, California
Stomach Upset
March 17, 2018
I provided the ComFortis tablet immediately following our dog’s breakfast. He vomited everything up within the hour. Gastrointestinal issues are not typical with our dog.
Cons
- Stomach upset.
By Ella P.
San Diego, California
Comfortis for Dogs
January 18, 2018
Very pleased with the service received. There were no discrepancies with the product, or with the order. The customer service was excellent and quite comforting. I would suggest that Entirely Pets is used for all of your pet needs.
Merchant Response:Thank you for your kind words Ella! Glad we are able to help!
Pros
- Good prices, order in a timely manner!
Cons
- No complaints!
By Orange m.
Huntington Beach California
Great product
October 5, 2017
The time it took to get the actual product was too long but the product itself and the price was great.
Cons
- Took too long
By Shelley
St. Louis, MO
Comfortis for dogs
October 4, 2017
good value, best price I could find
By Barcomb L.
Houston, Tx
Great product
April 23, 2017
Product works great. No live fleas found on my dog No scratching.Happy dog, 🐕
By pepperoni
san diego, California
Really effective; if only it weren't chewable
April 17, 2016
Great product but both dogs detest the flavor. So I'm left with huge pills I can't even disguise in food and it's the only medication I have to shove down their throats. Comfortis: PLEASE make a small pill that isn't chewable.
Pros
- effective
Cons
- dogs hate the taste and it's so strong I can't even disguise it covering it with blue cheese!
By holly
Old Fort, NC
works great!
April 4, 2016
I have used this product on my cats. it works really really well and I like it much better than the topical. I hate that stuff. they sleep in my bed and the thought of that getting wiped everywhere freaks me out. the pills are easy, not messy, and really work!!! although I haven't ordered from entirely pets yet, I am planning on using them for my next order because their prices a MUCH less than at the vet!
Pros
- works great, no mess, better prices than the vet
Cons
- none
By Vicky
McKinlyville CA
Finally NO FLEAs!
March 5, 2016
yày...this product actually works! I've spent hundreds of dollars trying to get the fleas off our Germàn Shepherd. For yearrs he would màke himself, ànd me, crazy and hairless from scratching at them. After 2 months, his hair is growing back now and he looks really nice and shiny and happy!! SSo glad I switched from topicals!
