Comfortis®(1620mg) 6 Chewable Tablets for Extra Large Sized Dogs 60.1-120lbs (27.1-54kg) EXP 11/2020

Comfortis® (spinosad) is a fast, safe and effective treatment for flea infestations on your dog or cat. It starts killing fleas faster than Nexgard® (afoxolaner)*,2, and in a controlled laboratory study in dogs, Comfortis killed 100% of the fleas in just four hours.

The worst part of a flea infestation is not what you can see–it's what you can't. Microscopic flea eggs, larvae and pupae can permeate your home and keep the flea infestation cycle going. Comfortis kills fleas before they lay eggs, and Comfortis keeps killing fleas for a full month with each dose. Use Comfortis for at least three months to treat a current flea infestation, then continue routine use to prevent a reinfestation on your pet. In a field study conducted in households with existing flea infestations in dogs, flea count reductions of 97.9% were observed one month after the first treatment and 99.9% after three monthly treatments with Comfortis.

With more than 80 million doses dispensed3, you can trust Comfortis when you want fleas dead and gone.

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.


Dogs & Cats (14 weeks of age or older)

  • 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.


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.

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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.

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