Sentinel Spectrum Chew for Dogs, 2-8 lbs, (Orange Box), 6 Chews (6-mos. supply)

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$54.99 Autoship Price
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$54.99 Chewy Price
($9.17 /ea)

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Usually arrives in 3-5 days
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About This Item

Details

  • Protects against 6 different types of parasites, including tapeworms.
  • Unique to SENTINEL brand products, lufenuron stops flea eggs from hatching.1
  • Protects against heartworms, tapeworms, hookworms, roundworms, and whipworms.1
  • SENTINEL SPECTRUM does all this with convenient and effective once-a-month dosing and a soft beef and bacon-flavor dogs love.2,3
  • 1SENTINEL SPECTRUM Chews [prescribing information]. Madison, NJ: Merck Animal Health; 2020. 2Data on file. Merck Animal Health. 3SENTINEL SPECTRUM CHEWS [Freedom of Information] NADA #141-333.

Ingredients

Instructions

FAQ

Learn More About Sentinel Spectrum From Our Team of Experts
4.8
Rated 4.8 out of 5 stars
297 Ratings

Customers Mention

Chewy identifies key considerations with the help of artificial intelligence and our veterinarians.

Ease of Use

91% Positive

Effectiveness

91% Positive

Ingredients

96% Positive

Long-Term Benefits

90% Positive

100 Customer Reviews



Always consult a veterinarian about your pet’s health needs. Customer reviews should not be used as medical advice.

Rated 5 out of 5 stars
By Stephanie787 on Aug 25, 2023

Heart worm/flea Protection

I used Sentinel for many years on my other dog who was MDR1 positive as many Aussies are. My new puppy is a toy Aussie. He is a little over 4 pounds now so I was

I used Sentinel for many years on my other dog who was MDR1 positive as many Aussies are. My new puppy is a toy Aussie. He is a little over 4 pounds now so I was happy to see that Sentinel comes in a dosage for small dogs. I urge all Aussie owners and Collie owners to have their pets checked for MDR1 and in my opinion to discontinue use of medications designed for multiple uses. To read the ingredients carefully. There have been several deaths which are not made public because of lack of information on the MDR1 Gene.


Rated 5 out of 5 stars
By BlkGaL on Oct 16, 2021

Very Pleased

Our Fur Son ITTY-BITTY only 6 lb (A MORKIE) we started him on Sentinel at his second vet appointment he's been on it ever since and he will be 1 on the 27th of this

Our Fur Son ITTY-BITTY only 6 lb (A MORKIE) we started him on Sentinel at his second vet appointment he's been on it ever since and he will be 1 on the 27th of this month I think Sentinel is awesome it works extremely well although he doesn't go outside at all unless he's unless it's appointments and when he does he's constantly his stroller therefore he doesn't be around dogs so I don't have to worry about the flea part but this does work apparently well against fleas as well he does not like it by itself so we literally always have to crush it up in little pieces to camouflage it with his wet food what they said I definitely recommend this product this will be my second 6 month supply


Rated 5 out of 5 stars
By Cristina on Nov 14, 2019

So far, so good!

I just moved to Florida and was recommended by a veterinarian to give my dog heartworm preventative due to the warmer climate. Well, so far, so good! She's

I just moved to Florida and was recommended by a veterinarian to give my dog heartworm preventative due to the warmer climate. Well, so far, so good! She's only on her first dosage, but she didn't hesitate and ate the pill with a little peanut butter. There was no vomiting afterward, nor have there been any changes in her behavior or negative reactions. What I liked most about this pill is that I didn't read any negative feedback on it while researching options. Some heartworm preventatives seem to have given dogs' seizures or life-threatening ailments. Knowing that information alone had me incredibly nervous to give her any heartworm treatment at all! I hope in the end, this is the brand I come back to for many years to come. From the looks of it, it seems to be a winner! I also liked the price-point. Super affordable!


Rated 5 out of 5 stars
By Sonia on Oct 9, 2025

For years I’ve trusted Sentinel to be safe for my babies

Well, it’s safe and works well for US. I know many pet owners don’t want to give lots of chemicals to their pets. This is the only medication I trust it would help

Well, it’s safe and works well for US. I know many pet owners don’t want to give lots of chemicals to their pets. This is the only medication I trust it would help to avoid heart worm, and aids in repelling fleas & ticks. My doggies love ti go exploring around in my backyard; Sentinel works like my guardian angel. Brings piece of mind since they love to run around in the backyard where lots of deer and other critters often are wandering, close to the house .


Rated 5 out of 5 stars
By Shelley on Aug 11, 2018

Works great!

I can always rely on this product to do its job. My dogs don’t particularly care for chewing the tablet but I can easily break it in half and disguise it by rolling

I can always rely on this product to do its job. My dogs don’t particularly care for chewing the tablet but I can easily break it in half and disguise it by rolling it in a piece of cheese.


Rated 4 out of 5 stars
By Terri on Dec 23, 2025

Great 4 Weight-loss

The price is reasonable. Was very easy process from getting the prescription sent to Chewy.com from my vet to getting it sent out from Chewy.com. My dogs all kinda

The price is reasonable. Was very easy process from getting the prescription sent to Chewy.com from my vet to getting it sent out from Chewy.com. My dogs all kinda share it. Their poops aren't runny or messy, they dont smell as bad either. We will keep on buying this as it helps keep the weight lowered in my senior, less active furbabies.


Rated 5 out of 5 stars
By Molly on Sep 28, 2025

Hard to find flea control

My old vet and my new vet no longer carry this product. Both vets tried to steer me to a more expensive flea control. My dogs are sensitive to medications, and since

My old vet and my new vet no longer carry this product. Both vets tried to steer me to a more expensive flea control. My dogs are sensitive to medications, and since this product works, I see no reason to change, especially if it is going to cost me more and possibly cause my dogs to have reactions from a different medication. So glad you carry Sentinel Spectrum!!


Rated 5 out of 5 stars
By Lana on Aug 3, 2024

Sentinel Spectrum

I have been giving this product to my dogs for years because it works! I highly recommend you try it and your dog(s) will benefit.

I have been giving this product to my dogs for years because it works! I highly recommend you try it and your dog(s) will benefit.


Rated 5 out of 5 stars
By MARK on May 14, 2025

Great product-Customer Service was outstanding!

We were camping out of state for 2 months and couldn’t find his once a month Sentinel Spectrum, thanks to Chewy we were able to have our get our prescription and

We were camping out of state for 2 months and couldn’t find his once a month Sentinel Spectrum, thanks to Chewy we were able to have our get our prescription and their customer service was amazing to work with, best of all, it was much cheaper then, Our local Veterinary. Thanks again!


Rated 5 out of 5 stars
By Koby on Jul 1, 2023
Top 250 Contributor

Good for heartworm prevention

People who are complaining that this doesn’t work on fleas it says so right in the product description. It only works on killing flea eggs, not on adult fleas,

People who are complaining that this doesn’t work on fleas it says so right in the product description. It only works on killing flea eggs, not on adult fleas, you will need something else for that (my vet gave me Vectra for that). The main thing I’m using it for is for heartworm prevention, but it also kills some worms and flea eggs. My dog ate it right down when I fed her her kibble. I cut it into quarters because her kibble is small and I didn’t want her not to eat the sentinel. The first piece she was a little leery of but after a little hesitation she ate it. She had no reaction to it at all which I’m very thankful for.