Sentinel Spectrum Chewable Tablets for Dogs, 8.1-25 lbs, 6 treatments

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Your furry friend must have a current heartworm test result on file with your veterinarian in order to be prescribed heartworm medication. Please visit your veterinarian to have this test performed annually to protect your four-legged friend. Sentinel Spectrum is a monthly oral preventive prescription that guards against heartworms, adult roundworms, adult hookworms, whipworms, and prevents the development of flea eggs. It protects your dog against heartworm disease and intestinal worms, all in a palatable, beef-flavored chewable.


Sentinel Spectrum is indicated for the prevention of heartworm disease. It is also formulated to help prevent and control flea populations, and for the treatment and control of adult roundworm, hookworm, whipworm, and tapeworm infections in dogs and puppies six weeks of age and older and weighing at least two pounds.

Possible Side Effects

The following adverse reactions have been reported in dogs after administration of milbemycin oxime, lufenuron, or praziquantel: vomiting, depression/lethargy, pruritus, urticaria, diarrhea, anorexia, skin congestion, ataxia, convulsions, salivation, and weakness.

Drug & Food Interactions

There are no known contraindications to the use of Sentinel Spectrum. 


Treatment with fewer than 6 monthly doses after the last exposure to mosquitoes may not provide complete heartworm prevention. Prior to administration of Sentinel Spectrum, dogs should be tested for existing heartworm infections. At the discretion of the veterinarian, infected dogs should be treated to remove adult heartworms. This medication is not effective against adult D. immitis. Mild, transient hypersensitivity reactions, such as labored breathing, vomiting, hypersalivation, and lethargy, have been noted in some dogs treated with milbemycin oxime carrying a high number of circulating microfilariae. These reactions are presumably caused by release of protein from dead or dying microfilariae. Do not use in puppies less than six weeks of age. Do not use in dogs or puppies less than two pounds of body weight. The safety of this medication has not been evaluated in dogs used for breeding or in lactating females. Studies have been performed with milbemycin oxime and lufenuron alone. Not for use in humans. Keep this and all drugs out of the reach of children.

  1. Prescribing Information

See all items by Sentinel Spectrum

  • Item Number
  • Brand

    Sentinel Spectrum

  • Dosage Measure

    Use according to your veterinarian's instructions.

  • Common Brand Name(s)

    Sentinel Spectrum

  • For Use With


  • Generic Name

    Milbemycin Oxime, Lufenuron, Praziquantel

  • Brand


  • Breed Size

    Extra Small & Toy Breeds, Small Breeds

  • Product Form

    Chewable Tablet

  • Health Condition

    Heartworms, Hookworms, Roundworms, Whipworms, Tapeworms, Fleas

  • Drug Type



Milbemycin Oxime, Lufenuron, Praziquantel n

Recommended Dosage

Sentinel Spectrum should be administered orally, once every month, at the minimum dosage of 0.23 mg/lb (0.5 mg/kg) milbemycin oxime, 4.55 mg/lb (10 mg/kg) lufenuron, and 2.28 mg/lb (5 mg/kg) praziquantel. For heartworm prevention,ngive once monthly for at least 6 months after exposure to mosquitoes.

Storage Instructions

Store in a dry place at controlled room temperature between 59° - 77°F.

SENTINEL SPECTRUM should be administered orally, once every month, at the minimum dosage. To ensure adequate absorption, always administer SENTINEL SPECTRUM to dogs immediately after or in conjunction with a normal meal. The chewables should be administered in a manner that encourages the dog to chew, rather than to swallow without chewing. Chewables may be broken into pieces and fed to dogs that normally swallow treats whole. Care should be taken that the dog consumes the complete dose, and treated animals should be observed a few minutes after administration to ensure that no part of the dose is lost or rejected. If it is suspected that any of the dose has been lost, redosing is recommended.

Heartworm Prevention: SENTINEL SPECTRUM should be administered at monthly intervals beginning within 1 month of the dog’s first seasonal exposure to mosquitoes and continuing until at least 6 months after the dog’s last seasonal exposure. SENTINEL SPECTRUM may be administered year-round without interruption. When switching from another heartworm preventative product to SENTINEL SPECTRUM, the first dose of SENTINEL SPECTRUM should be given within a month of the last dose of the former product.

Flea Treatment and Prevention: Treatment with SENTINEL SPECTRUM may begin at any time of the year, preferably starting one month before fleas become active and continuing monthly through the end of flea season. In areas where fleas are common year-round, monthly treatment with SENTINEL SPECTRUM should continue the entire year without interruption. To minimize the likelihood of flea reinfestation, it is important to treat all animals within a household with an approved flea protection product, as necessary.

Intestinal Nematode and Cestode Treatment and Control: Dogs may be exposed to and can become infected with roundworms, whipworms, hookworms, and tapeworms throughout the year, regardless of season or climate. Clients should be advised of appropriate measures to prevent reinfection of their dog with intestinal parasites. Because the prepatent period for E. multilocularis may be as short as 26 days, dogs treated at the labeled monthly intervals may become reinfected and shed eggs between treatments.


How are Sentinel Spectrum and Sentinel Flavor Tabs different from other heartworm medications?

Not all heartworm medicines provide the same spectrum of parasite protection. Sentinel Flavor Tabs are chewable tablets that protect dogs against fleas, heartworms, roundworms, hookworms, and whipworms. Sentinel Spectrum is a soft, beef and bacon flavored chew that adds tapeworm protection to offer the broadest coverage available.

My dog weighs more than 100 pounds. Are Sentinel Specturm or Sentinel Flavor Tabs a good option for him?

Yes. Talk to your veterinarian about the appropriate dose for your pet.

My dog is a toy breed. Are Sentinel Specturm or Sentinel Flavor Tabs okay for his small size?

Yes. Both Sentinel Specturm and Sentinel Flavor Tabs offer a size that can be given to small dogs. Sentinel Spectrum has a size available for dogs weighing from 2–8 lbs and Sentinel Flavor Tabs has a size available for dogs weighing from 2–10 lbs.

I see a few fleas on my dog. Is the medication working?

You may see an occasional “hitchhiker” adult flea that your dog has picked up at the dog park or in the yard or other infested environments where 95% of the flea population lives in the form of eggs, maggot-like larvae, and pupae. Sentinel Specturm and Sentinel Flavor Tabs put an end to fleas before they become adults. You may need an adulticide, such as Effitix Topical Solution for Dogs, to treat occasional adult fleas.

Can I give either Sentinel Spectrum or Sentinel Flavor Tabs to my cat?

No, both Sentinel Spectrum and Sentinel Flavor Tabs are only approved for use in dogs.

Customer Reviews
11 Reviews 11 Reviews 4.7 out of 5 Stars

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100% of reviewersrecommend this product

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  • ALL-in-ONE

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    Not only do my puppets take this medicine like a treat because its chewy unlike the horrible-smelling tablets I was using before. I also don't have to buy more than one type of heartworm medicine because the weight range is perfect so as to include both my yorkie-mix and my schnauzer-mix. It also includes fleas protection; best medicine!

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  • great medication

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    Sentinel has been around for years the spectrum it is a plus - all my dogs do well with this product and with 9 dogs I needed a product that worked well with out the high cost wish I knew about it sooner then I did

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  • Insulin for my DogTer

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    I am so excited that Chewy now offers medications!! And at such a great price!! I now can purchase all of my DogTer’s medications from one place and have it delivered right to my door. The only complaint that I have is that it took 4-5 days to get it prepared to ship. But I’ll excuse it as this is a new service.

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  • First time user

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    This is the first time we used Chewy Prescriptions as our vet no longer carriers Sentinel. Chewy was very professional,comparably priced and quite fast! We are very pleased and will continue to use the service.. WE are also very happy with the Sentinel, great results and will continue to use it

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  • Great product

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    Haven't had any issues with fleas or worms since using this product for a year now. My dog used to eat it like it was a treat but now I fight her to take it every month. I started cutting it up and mixing it with some wet dog food and she eats it without even knowing.

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  • Woof Woof kudos to Olivia and Jay .

    By on

    Olivia and Jay were so pleasant and funny with the canine references used in their responses to my emails . They made me laugh and I truly enjoyed the doggie humor . Keep it up . Other than a small snafu with my Vets office getting the prescription faxed { Olivia actually called them and cleared it up} . I couldn't be happier with my order . I am so glad Chewy is caring prescription items I need for my two little girls .

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  • Momma To Gizzie And Colahev

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    Awesome product that I've given all my dogs since it came on the market. Sentinel is easy to administer as my dogs think it's a treat. GREAT PRODUCT

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  • These work great!

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    These are great...the dogs gobbled them right up. No muss, no fuss, just quick and easy. And the fact that they work for heartworm and fleas is fantastic news. Buy some.

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  • Sentinel Spectrum

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    My dog thinks it is a treat, although a chewy treat, it seems to work for Him. No sighing ,no fleas, etc. price seems to be comparable to others on the market.

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  • Sentinel Spectrum

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    Have used them for years. No noticeable side effects.

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