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Comfortis

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Product Info
How to Use
Ingredients
Customer Reviews
Q&A
Product Info
What is Comfortis?

Comfortis is the first FDA-approved, chewable beef-flavored tablet that kills fleas and prevents flea infestations on dogs and cats for a full month. Comfortis for Dogs & Cats requires a prescription from your veterinarian.

For:

Dogs & Cats (14 weeks of age or older)

Benefits:
  • Starts killing fleas within 30 minutes
  • Lasts a full month
  • Kills fleas before they can lay eggs
  • Comes in a convenient chewable, beef-flavored tablet
  • Spinosad, the active ingredient in Comfortis, is environmentally friendly
How it Works:

Spinosad kills fleas by causing excitation of the insect's nervous system, leading to paralysis and rapid death.

Cautions:

Side effects may occur, including vomiting. If your pet is experiencing loss of appetite, lethargy, or any other difference in behavior, contact your veterinarian. The FDA has received reports of adverse reactions in dogs receiving the drug Comfortis (spinosad) concurrently with high, extra-label doses of ivermectin. Dogs receiving extra-label doses of ivermectin to treat non-responsive demodectic mange and other conditions have developed signs of ivermectin toxicity. Ivermectin is an ingredient found in heartworm preventatives such as Heartgard Plus, Heartgard, Iverhart Plus and Ivomec. In cats, the most common adverse reaction recorded in clinical trials was vomiting. Other adverse reactions were: lethargy, decreased appetite, weight loss, and diarrhea. Use with caution with concomitant extra-label use of ivermectin.

Brand Name:

Comfortis (Lilly)

Generic Name:

Spinosad

What is Comfortis:

Comfortis is a chewable, synthetic beef flavored tablet (derived from pork protein and hydrolyzed soy) that is given to a dog or cat to kill fleas and prevent flea infestations for one month. Comfortis chewable tablets are for monthly use in dogs and puppies or cats and kittens 14 weeks of age and older.

What should I discuss with my veterinarian before giving Comfortis to my pet:

Tell your veterinarian if you are planning on breeding your pet. Tell your veterinarian if your dog or cat has a history of seizures (epilepsy).

What is the most important information I should know about Comfortis:

Comfortis is a prescription medication FDA approved for use in dogs and puppies and cats and kittens 14 weeks of age or older to kill fleas and prevent flea infestations for one month. Comfortis is available in a Yellow box for dogs 3.3 to 4.9 lbs and cats 2-4 lbs (90mg), Pink box for dogs 5 to 10 lbs and cats 4-6 lbs (140mg), Orange box for dogs 10.1 to 20 lbs and cats 6.1-12 lbs (270mg), Green box for dogs 20.1 to 40 lbs and cats 12.1-24 (560mg), Blue box for dogs 40.1 to 60 lbs (810mg), and Brown box for dogs 60.1 to 120 lbs (1620mg). Please note: Cats over 24 lbs should be administered the appropriate combination of tablets.

How should this medication be given:

Give Comfortis chewable tablets with food. Give Comfortis chewable tablets once a month. Comfortis chewable tablets may be chewed, offered in food, or administered like other tablet medications. If vomiting occurs within 1 hour of administration, redose the pet with another full dose. Store Comfortis at room temperature (68-77° F)

What should I avoid while giving Comfortis:

Your pet may maintain normal activities and interactions while being given Comfortis. The safe use of Comfortis in breeding, pregnant, or lactating cats and dogs has not been evaluated.

What are the possible side effects of Comfortis:

Side effects that may occur include vomiting. If vomiting occurs within one hour of administration, redose with another full dose. Other side effects may occur. Continue giving Comfortis chewable tablets and talk to your veterinarian if your pet experiences decreased appetite, lethargy or decreased activity, diarrhea, cough, increased thirst, vocalization, increased appetite, redness of the skin, hyperactivity and excessive salivation. Talk to your veterinarian about any side effect that seems unusual or especially bothersome to the pet.

What other drugs will affect Comfortis:

Talk to your veterinarian before giving any prescription or over the counter medications.

How to Use
Directions:
  • Comfortis is a prescription medication used in dogs to kill fleas and prevent flea infestations for 1 month.
  • Comfortis chewable tablets are beef flavored.
  • Comfortis can be given to dogs at least 14 weeks of age, weighing at least 3.3 lbs, and cats 14 weeks of age, weighing at least 2 lbs.
Tip:

If vomiting occurs within 1 hour of administration, redose the pet with another tablet.

Dosage:
Dogs/Puppies: (14 weeks of age or older)
Weight
Dosage
3.3-4.9 lbs (Yellow Box)
Give one 90mg chewable tablet by mouth once a month. Comfortis may be chewed, offered in food, or administered like other tablet medications
5-10 lbs (Pink Box)
Give one 140mg chewable tablet by mouth once a month. Comfortis may be chewed, offered in food, or administered like other tablet medications
10.1-20 lbs (Orange Box)
Give one 270mg chewable tablet by mouth once a month. Comfortis may be chewed, offered in food, or administered like other tablet medications
20.1-40 lbs (Green Box)
Give one 560mg chewable tablet by mouth once a month. Comfortis may be chewed, offered in food, or administered like other tablet medications
40.1-60 lbs (Blue Box)
Give one 810mg chewable tablet by mouth once a month. Comfortis may be chewed, offered in food, or administered like other tablet medications
60.1-120 lbs (Brown Box)
Give one 1620mg chewable tablet by mouth once a month. Comfortis may be chewed, offered in food, or administered like other tablet medications
Over 120 lbs
Give the appropriate combination of tablets
Cats/Kittens: (14 weeks of age or older)
Weight
Dosage
2-4 lbs (Yellow Box)
Give one 90mg chewable tablet by mouth once a month. Comfortis may be chewed, offered in food, or administered like other tablet medications
4-6 lbs (Pink Box)
Give one 140mg chewable tablet by mouth once a month. Comfortis may be chewed, offered in food, or administered like other tablet medications
6.1-12 lbs (Orange Box)
Give one 270mg chewable tablet by mouth once a month. Comfortis may be chewed, offered in food, or administered like other tablet medications
12.1-24* lbs (Green Box)
Give one 560mg chewable tablet by mouth once a month. Comfortis may be chewed, offered in food, or administered like other tablet medications
Horses:
Do not use!
Storage:

Store Comfortis at room temperature (68°-77° F).

Ingredients
Comfortis for Dogs: 3.3-4.9 lbs - Comfortis for Cats: 2-4 lbs (Yellow Box)
Active Ingredient
Amount
Spinosad
90 mg
Comfortis for Dogs: 5-10 lbs - Comfortis for Cats: 4-6 lbs (Pink Box)
Active Ingredient
Amount
Spinosad
140 mg
Comfortis for Dogs 10.1-20 lbs - Comfortis for Cats: 6.1-12 lbs (Orange Box)
Active Ingredient
Amount
Spinosad
270 mg
Comfortis for Dogs 20.1-40 lbs - Comfortis for Cats: 12.1-24 lbs (Green Box)
Active Ingredient
Amount
Spinosad
560 mg
Comfortis for Dogs 40.1-60 lbs (Blue Box)
Active Ingredient
Amount
Spinosad
810 mg
Comfortis for Dogs 60.1-120 lbs (Brown Box)
Active Ingredient
Amount
Spinosad
1,620 mg
Customer Reviews
Comfortis is rated 4.5 out of 5 by 1119.
Rated 3 out of 5 by from Kills fleas, huge disgusting pill! Comfortis works great on fleas, but it is so large I have to cut it in half. It smells so bad that my cat starts to avoid me, and now I have to try to get two pill pieces down her throat. I'm switching back to drops. I had hoped that this was a smaller pill or perhaps that it was flavored, but oh man is my cat disgusted with it. She spits it up and once it gets moist you can't easily get it down. I mixed a wet pill half into tuna but she wouldn't touch it.
Date published: 2017-02-11
Rated 5 out of 5 by from Immediate results! My Himalayan is very sensitive to flea bites and nothing else has worked. Within one hour of taking Comfortis the fleas were dropping off - dead! He's back to his same old self.
Date published: 2017-02-07
Rated 5 out of 5 by from Works great but has side effects Com fortis was suggested by our vet. It works very well, and works quickly. The only problem was a side effect-severe itching that lasted all night. But, I would use it again.
Date published: 2017-02-06
Rated 5 out of 5 by from Work GREAT If only I could find an easier way for her to take them. We have tried everything and resorted to staving her then crush and mixing it into tuna; she eats it but hates it. Wish there was a better way.
Date published: 2017-01-30
Rated 5 out of 5 by from Great product My American bulldog is a flea magnet & this is the only product I've found that works!
Date published: 2017-01-29
Rated 5 out of 5 by from Great flea medication I switch my Maltese to comfortis almost a year ago after she developed a side effect on other flea medication. Comfortis works immediately with no signs of discomfort to her. I never heard of comfortis until it was recommended to me by my dog breeder.
Date published: 2017-01-26
Rated 5 out of 5 by from Worked for all my cats For my cats, the fleas started to die and fall off within 30 minutes. They have been on comfortis for about a year, and I am happy with the results.
Date published: 2017-01-23
Rated 5 out of 5 by from No side effects I switched both our dogs to Comfortis after my pug developed a severe reaction (hot spot) to another topical flea medication. We've been using Comfortis monthly for nearly a year now and no side effects and no fleas!
Date published: 2017-01-16
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Q&A

my english mastiff is 200lbs would i have to give him to pills?

Asked by: maria
Yes, you would have to give your dog 2 of the 60-120 pound tablets, but double check with your veterinarian just in case he/she is concerned about other issues that may be affected by that much Comfortis.
Answered by: SuzyCVT
Date published: 2017-02-09

is comfortus for cats different than comfortis for dogs?

Asked by: deegee
No, it is the same product, but cats take a different strength per pound so use the appropriate size indicated for cats, not dogs.
Answered by: SuzyCVT
Date published: 2017-02-07

Can you cut a comfortis pill for 20-40 lb. in half so you can treat 2 smaller dogs?

Asked by: Maxie
It is never recommended to cut any chewable medication (or non-scored tablets) in half to give to 2 different pets as the active ingredient may not be evenly distributed throughout the tablet.
Answered by: SuzyCVT
Date published: 2017-01-27

How long does it takes the pill to work 

Asked by: Shay30
Comfortis starts killing fleas once it is absorbed into the system, usually within an hour after ingestion.
Answered by: SuzyCVT
Date published: 2017-01-27

What dose the pill look like??

Asked by: Brat Kat mo
It is a tan-colored, round chewable tablet.
Answered by: SuzyCVT
Date published: 2017-01-27

Can I buy a 3 month supply?

Asked by: Arvay1
PetMeds only sells Comfortis as a 6-pack or 12-pack. The manufacturer does not make a 3-pack. Your veterinarian may be able to sell you Comfortis in lesser quantities.
Answered by: SuzyCVT
Date published: 2017-01-07

Does comfortis kill chewing lice on dogs

Asked by: Bettyh
The product label does not state that Comfortis kills chewing lice.
Answered by: SuzyCVT
Date published: 2017-01-07

Does comfortis kill the chewing lice also?

Asked by: Bettyh
The product label does not state that Comfortis kills chewing lice.
Answered by: SuzyCVT
Date published: 2017-01-07
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