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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 4.5302 out of 5 by 1,109.
Rated 5 out of 5 by from Works great!! It works fast!! No more fleas!!!! I gave it to my dog and cat they ate both flea free, no more scratching. The flavor must be great, because my very very picky cat even ate the tablet???!!!!! I couldn't be more happy with the results. Will definitely reorder when needed!! Thank you!!!
Date published: 2016-12-03
Rated 5 out of 5 by from Works great. Not chewable Works great at protection but my dogs refuse to eat it. I have to shove it into the throat like other medication. For all practical purposes, this is not a chewable item.
Date published: 2016-12-02
Rated 5 out of 5 by from Comfortis is the best thing out there in my opinio I had to cancel my last order though because, after doing this for a while, my vet, out of the blue, tried to make it where I had to take my dog in for an examination. Which is odd because that is usually only done on new clients. Duke has been to my vet many times. When I first adopted him he had heartworms. Anyways. Comfortis is great. Now I have to find a new vet. Going back to Advantage for my dog now. I won't be forced to buy something in any vet office just because that is what they choose to sell. 1800petmeds is great and will always go through them when I need to.
Date published: 2016-11-29
Rated 5 out of 5 by from Best Option That Isn't Topical! I was trying to find alternatives for the topical treatment, as my cat has feline hyperesthesia, and anything touching him gives him panic attacks. I put this pill right in his wet food and he gobbled it all up and didn't even notice! Within 30 minutes I found several fleas dead already. I think this is an excellent alternative to topical treatment, and MUCH easier! No mess, no stink, and you can pet your animal on their back whenever. I love this product. Highly recommended.
Date published: 2016-11-27
Rated 5 out of 5 by from Only Flea Killer That Works! I bought this for my 11 lb. Yorkie who goes everywhere with us including our island camp where the fleas are relentless. She had to have a bath every time we came home just to get the fleas off her. Her groomer told me about Comfortis, so I called my vet and bought Comfortis. The fleas actually fell off dead in about an hour. I was worried how it would affect my little pooch, so I watched her closely and she had no adverse reaction. I am sold! I ordered Comfortis from 1800-PetMeds.com and saved some bucks too, so it was a double whammy happy day!
Date published: 2016-11-14
Rated 2 out of 5 by from Makes my lab sick I was excited to try this, even though it is costly. My 6 year old lab throws up within a couple hours of taking it. After 3 months (doses), can't continue with Comfortis.
Date published: 2016-11-12
Rated 3 out of 5 by from It sorta works I bought this because I have 2 dogs, and took in recently 2 stray kittens. Sadly the kittens had fleas, and nothing worked to help them, so it spread to my dogs. The vet recommended comfortis to help my poor dogs and kitties. It did work to an extent within an hour living and dead fleas were jumping off my babies. Which made a big difference, but a few days later a flea was spotted on my dog, so while it killed most it hasn't ended my poor babies problem.
Date published: 2016-10-24
Rated 5 out of 5 by from I'm glad I switched flea products Comfortis quickly resolved our flea issues and no side effects as experienced with another product
Date published: 2016-10-18
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Q&A

Comfortis will continue to work for 30 days against any new fleas or ticks that may jump on dogs?

Asked by: Alhy
Yes, Comfortis is a chewable beef-flavored tablet that kills fleas and prevents flea infestations on dogs and cats for a full month.
Answered by: Lisa M
Date published: 2016-12-01

Can I break up this comfortis pill and mix it in the wet food?

Asked by: Cats meow
Although not recommended, some veterinarians instruct owners to break the Comfortis tablet. Consult your veterinarian for his/her professional opinion.
Answered by: Lisa M
Date published: 2016-11-25

Do i give it on the same day every month or 30 days from the last tablet? 

Asked by: DaNita
Same date each month, which will be 30 days from your last dose.
Answered by: S Duesler PharmD MBA
Date published: 2016-11-17

My dogs hate this product.They will not take this alone; when I tried to hide in food, they eat the food, and leave tthe pill. They are not both fussy eaters. One is a Basset; And she'll eat anything. Any suggestions?

Asked by: TKTWD
You may try hiding the pill in pill pocket treats which can be found on our website.
Answered by: S Duesler PharmD MBA
Date published: 2016-11-17

Can I pay for an order with Care Credit ?

Asked by: Melissia
Please contact our sales department.
Answered by: S Duesler PharmD MBA
Date published: 2016-11-17

I recently ordered Comfortis for my cat. However, the package that I got only listed dogs information on it. It is 270mg and has listed kg instead of pounds 4.5-9 kg is this safe for my cat to take. Are there certain ingredients I needs to look for?

Asked by: jknox
Comfortis 270 mg is appropriate for cats weighing 6 to 12 pounds.
Answered by: Lisa M
Date published: 2016-11-17

Does comfort is kill ear mites in cats

Asked by: lozzer
Spinosad, the active ingredient in Comfortis, kills fleas by causing excitation of the insect's nervous system, leading to paralysis and rapid death.
Answered by: Lisa M
Date published: 2016-11-17

Does this medicine kill fleas on dog already.  And then prevents from getting? 

Asked by: Mimzy
Spinosad, the active ingredient in Comfortis, kills fleas by causing excitation of the insect's nervous system, leading to paralysis and rapid death.
Answered by: Lisa M
Date published: 2016-11-16
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