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Sentinel Spectrum Chew for Dogs, 50.1-100 lbs, (Blue Box), 6 Chews (6-mos. supply)

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$81.99 Autoship Price
  • Never miss a dose with easy refills
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$81.99 Chewy Price
($13.67 /ea)
In Stock
FREE delivery
Usually arrives in 3-5 days
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No Interest if paid in full in 6 months on PayPal purchases of $149+. .

Medications ship separately. Delivery times may vary.

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.

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Reviews
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4.8
Rated 4.8 out of 5 stars
1649 Ratings
Terms & Conditions

Customers Mention

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

Ease of Use

94% Positive

Effectiveness

91% Positive

Ingredients

89% Positive

Long-Term Benefits

91% Positive

507 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
Verified Purchase
By Sylvie on Jun 10, 2025

Working with me!!!

I love love love that the Chewy team worked with me! My pup Dory is dying of terminal cancer and may only be around for a few months. On April 1st I was told she

I love love love that the Chewy team worked with me! My pup Dory is dying of terminal cancer and may only be around for a few months. On April 1st I was told she had 150 days left and Chewy worked with me so that I only had to pay for 4 month of Sentinel and I get to keep my costs low as I am also paying for her chemo. These people are amazing and so so thoughtful! They also sent me a plush! Which is awesome but unfortunately she doesn't play with toys, she loves treats and food but has lots of allergies, she can have most exotics but honestly I'm letting her have whatever because she's dying. Again I love love love you guys!!!

Rated 5 out of 5 stars
Verified Purchase
By Ashley on Feb 24, 2026

Great product

This is such a great product! It’s the most cost effective and efficient product out there. I don’t trust any products that my veterinarian wouldn’t recommend I.e

This is such a great product! It’s the most cost effective and efficient product out there. I don’t trust any products that my veterinarian wouldn’t recommend I.e. all of those over the counter products but I also can’t afford $200 for 6 months of a product or less.

Rated 5 out of 5 stars
By dogmomma94 on Jul 16, 2021
Top 1000 Contributor

Works Great When Paired Wirh Vectra 3D

I use Sentinel Spectrum and Vectra 3D for my babies and we’ve never had an issue. Alone they aren’t as effective. Together they repel and kill almost everything

I use Sentinel Spectrum and Vectra 3D for my babies and we’ve never had an issue. Alone they aren’t as effective. Together they repel and kill almost everything. Kills and repels 4 different ticks, repels mosquitoes, biting flies, mites, all life stages of fleas, heart worms, hook round tape and whip worms. And with this combo, ticks don’t even have to bite for the medication to kill them so less of a worry of tick borne diseases. I was using Revolution but my German Shepherd ended up with Lyme disease because that particular medication only does one tick and unfortunately it isn’t even the one that carries Lyme. Would recommend this combo to any pet owner! Peace of mind is priceless.

Rated 5 out of 5 stars
Verified Purchase
By Brenda on Jan 4, 2025

Used for years

Have used on our various dogs going back over 25 years without a single problem. Only wish we could still just upload the written rx instead of mailing it. Would

Have used on our various dogs going back over 25 years without a single problem. Only wish we could still just upload the written rx instead of mailing it. Would make things much simpler. All but one dog out of eight loved it, the one needed cheese.

Rated 5 out of 5 stars
Verified Purchase
By Elise on Apr 28, 2023

Sentinel Spectrum - Heartworm Free!

I have been using Sentinel Spectrum chews for over a year now per the recommendation of my veterinarian. I got a prescription through Chewy after my dogs hit 50+

I have been using Sentinel Spectrum chews for over a year now per the recommendation of my veterinarian. I got a prescription through Chewy after my dogs hit 50+ pounds. It's wonderful not having to drive back and forth to the vet all the time just to get heartworm medication. The process of delivery was quick and easy. My Malinois just got her heartworm test yesterday and it came back negative. Her fecal tests have been coming back negative too for parasites. My only complaint is I wish the chews were softer or more appealing to dogs. My girls will usually eat anything but spit these out. We mix it in different foods and they gobble it right down. We will continue to use this product for years to come. :)

Rated 5 out of 5 stars
Verified Purchase
By Nickid2b on Mar 12, 2019

This Heartworm/Flea Works for Us

Over the past 15 years we have used different heartworm pills and heartworm/flea combo pills. This combination pill works best for us and is in our price range

Over the past 15 years we have used different heartworm pills and heartworm/flea combo pills. This combination pill works best for us and is in our price range. Hopefully after reading the discription you know it prevents flea eggs from hatching, but does not kill adult fleas that may get on your pet. Make sure you understand this otherwise you will be unsatisfied. If you want a combo pill that kills adult fleas you need to get a different brand. This combo heartworm/flea preventative is within our price range. We have 3 large dogs, all 50+ pounds. For the past two years we have given our dogs Bravecto which is an oral 3 month flea preventative that kills adults, larvae and eggs in addition to Sentinel Spectrum. Usually it is given to our crew in mid-August since that’s when fleas get worse in our area. Plus it lasts until it freezes outside. It’s cost efficient for us to buy Sentinel Spectrum year round and one Bravecto vs buying a combination heartworm/flea preventative like Trifexis year round. If you are in a warmer region where fleas are a problem year round, a different brand might be a better choice and more cost efficiencent for you. Do your research. We have been loyal Sentinel Spectrum users for over 6 years now!

Rated 3 out of 5 stars
Verified Purchase
By Ruger on Jun 8, 2022

Not sure what I think yet

I was picturing a pill so I guess I should have read the reviews more thoroughly. It's a fairly large snack-like morsal. I gave it to my Shepard/Malinois (who eats

I was picturing a pill so I guess I should have read the reviews more thoroughly. It's a fairly large snack-like morsal. I gave it to my Shepard/Malinois (who eats anything) and he did take it initially eating half before realizing he did NOT like it. It was almost impossible to get him to eat the other half and I did everything short of shoving it down his throat. It took 2 days of tricking him into it by cutting it very small and adding it to his dry food if I put too much he'd refuse to eat the rest of his food and I'd have to give him another meal without it before trying again. I can't say anything on the effectiveness of the actual meds yet since it's only been a couple days but hope it was worth the effort. I'm not looking forward to doing this every month to make it through the 6 month supply. The topical gels are way too hard to get down onto his skin with the 3" fur on his neck so I thought this would be a better method. Silly me! You can see by the look on his face that he shunned me for days afterwards.

Rated 5 out of 5 stars
Verified Purchase
By Amanda on May 14, 2025

The only one my dog will eat

I have sworn by sentinel products for many years! Recently we adopted a dog and the vet put him on simparica. He hated it and I had to really force him to eat it

I have sworn by sentinel products for many years! Recently we adopted a dog and the vet put him on simparica. He hated it and I had to really force him to eat it. With sentinel just like my other dogs he eats it willingly and has had no issues. The other medication made him itch and sick to his stomach. It protects against everything and now we're both happy.

Rated 4 out of 5 stars
Verified Purchase
By AbbeyOMy on Dec 2, 2021

Necessary Evil

I firmly believe that we need to do what's necessary to protect our loved pets from the dangers of heartworms and other parasites. I think Sentinel Spectrum chews

I firmly believe that we need to do what's necessary to protect our loved pets from the dangers of heartworms and other parasites. I think Sentinel Spectrum chews are a great way of doing that. My only complaint is their taste. Apparently, it's not good... my dog won't eat them unless I chop the chew into about 8 pieces and roll them in gravy or peanut butter. Hopefully, they'll produce a better, more desirable chew in the future!

Rated 5 out of 5 stars
Verified Purchase
By Vivian on Sep 29, 2025

Love that it is a chewable

I used to get my boy the sentinel tablets, but he would not eat them! I had to cut them up and put them in pill pockets, but he would still manage to eat the pill

I used to get my boy the sentinel tablets, but he would not eat them! I had to cut them up and put them in pill pockets, but he would still manage to eat the pill pocket and spit out the pill! SMH! Now, with these chewable s, he thinks I am giving him a treat and eats it right up, taking away my worries about heartworm, fleas, and ticks.