Sentinel Spectrum Chew for Dogs, 8.1-25 lbs, (Green Box), 6 Chews (6-mos. supply)

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$56.99 Autoship Price
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$56.99 Chewy Price
($9.50 /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
1603 Ratings

Customers Mention

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

Ease of Use

94% Positive

Effectiveness

93% Positive

Ingredients

91% Positive

Long-Term Benefits

94% Positive

504 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 April on Jun 9, 2020

Does the job at a great price!

For most of my life, I used Revolution on both my dogs and cats. To this day it's still a great product, but it is very difficult to effectively put it on your pet

For most of my life, I used Revolution on both my dogs and cats. To this day it's still a great product, but it is very difficult to effectively put it on your pet if they have a thick double coat or waterproof coat. I then switched to Interceptor Plus + Nexguard for my dogs. Also great, but suuuuuuuper expensive. Then I discovered this! I don't know how they sell for so much cheaper than their competitors, but I'm not complaining. It has the same active ingredients as Interceptor Plus, and an active ingredient in the same chemical family as Nexguard, so they both work the same and have the same side effects. My dogs really test out their flea meds because we like to go hiking and they like to play in water and mud that is carrying who knows what. But, no fleas and no worms! If your dog does get worms while on any flea med, learn how dogs get worms and how flea meds work before getting angry. Praziquantel is the dewormer in this med, in many other flea meds, and in what the vet gives you when your dog or cat has worms. This chemical does not actively prevent worms; it kills whatever already exists. Then, the flea prevention should stop your dog from getting worms again for that entire month. But, if your dog ingests a flea carrying tapeworm just by being outside or from another animal or by a random hitchhiker that wasn't killed yet by the flea med, it can still get worms. This doesn't mean the flea med wasn't working appropriately. It just means we haven't invented a med yet that makes your pets completely impervious to parasites.


Rated 5 out of 5 stars
By HappyCustomer on Jul 27, 2021

Sentinel Spectrum Rx

Chewy's customer service reps and communication are incredible. INCREDIBLE. They have been very helpful on numerous occasions, such as when contacting my vet for

Chewy's customer service reps and communication are incredible. INCREDIBLE. They have been very helpful on numerous occasions, such as when contacting my vet for RXs, updating me on progress regarding a delay in my order, etc. They even send my toy poodle birthday cards each year. So sweet! I really appreciate Chewy. (Oh yeah, I almost forgot to review the product....Sentinel Spectrum is awesome in protecting my poodle from a vast array of pesky problems. I give it to her every month without fail, even though she spends 99% of her life inside. If you have ever seen a mosquito or tick inside your house/apartment, then you STILL MUST PROTECT your furbaby....no matter how little time it spends outside. BTW: My toy poodle weighs 6.8 pounds and I give her monthly dose to her on the last weekend (Friday) of each month, because it tends to upset her tummy, which requires more potty breaks. Giving it to her on the weekend allows for me to be home with her more, thus making the added potty breaks more convenient than if I were at work during the week. I am not saying that this RX will do that to YOUR pet, but my little girl has a sensitive stomach, so this is just what I've learned works best for us.) I HIGHLY recommend Chewy AND this RX.


Rated 5 out of 5 stars
By Nancy on Nov 22, 2025

Glad it’s still available

This is a very effective medication. We never have a problem with fleas and I don’t have to worry about heartworm as long as I’m using product. In the summer, I

This is a very effective medication. We never have a problem with fleas and I don’t have to worry about heartworm as long as I’m using product. In the summer, I use a flea and tick spray if there’s a problem with ticks, but there’s generally not a problem where I . Very happy with this product. I’ve used it for 10 years.


Rated 5 out of 5 stars
By Stephanie on Apr 14, 2024

Stick with What They're Used to

i adopted BuddyWhite when he was 11 and asked the rescue what he was taking for flea/heartworm prevention. It was Sentinel Spectrum chews. I stuck with this product

i adopted BuddyWhite when he was 11 and asked the rescue what he was taking for flea/heartworm prevention. It was Sentinel Spectrum chews. I stuck with this product only because I knew he was already used to it. Also, he sees it as a treat, which is great. I have a bunch of indoor cats and I hate to bring fleas in from outside. For the past 2.5 years, my house has been flea free! So awesome.


Rated 5 out of 5 stars
By Rebekah on Nov 8, 2018

ALL-in-ONE

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

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!


Rated 5 out of 5 stars
By Randy on Sep 12, 2025

It works!

Been using this for years. Heart Worm plus flea protection. No flea drops needed. Yes, occasionally she gets a flea on her foot until she bites it, but have never

Been using this for years. Heart Worm plus flea protection. No flea drops needed. Yes, occasionally she gets a flea on her foot until she bites it, but have never seen a flea on her body. Once a month pill.


Rated 4 out of 5 stars
By Angela on Apr 2, 2026

Works well, however..

This product has never failed us as far as prevention goes, but I did knock a star off because none of our dogs have ever willingly eaten it. They hate the flavor

This product has never failed us as far as prevention goes, but I did knock a star off because none of our dogs have ever willingly eaten it. They hate the flavor enough to pick it out of peanut butter, soft bread, cheese, pill pockets, etc. (and these are dogs who normally gobble up anything). We have to break it into smaller pieces and “pill” them by forcing them to swallow. Not a fun time, but the protection it offers is important in our geographical area.


Rated 5 out of 5 stars
By Laura on Jun 20, 2024

Love the choices

Sentinel spectrum is just what I needed! Where I live fleas, ticks, & mosquitoes are rampant! Not only does this prevent heartworms, but helps with the other pests

Sentinel spectrum is just what I needed! Where I live fleas, ticks, & mosquitoes are rampant! Not only does this prevent heartworms, but helps with the other pests. She thinks they are yummy, so there's no problem with her taking them.


Rated 5 out of 5 stars
By Nicole on Mar 20, 2025

Rough start, ended ok.

I inadvertently sent a script in and forgot to put in the order number (my bad). I tried so many time thorough chat to get someone to help, I was repeatedly pushed

I inadvertently sent a script in and forgot to put in the order number (my bad). I tried so many time thorough chat to get someone to help, I was repeatedly pushed off to different Depts. to no avail. Finally I reached a very pleasant Pharmacist who with minutes called my Vet. confirmed my scriptand had it sent out the same day. That's the customer service I expect from Chewy, we all have bad days.


Rated 5 out of 5 stars
By Jean on Mar 18, 2026

Prevent fleas and ticks.

He's just the medicine for both of my pets I live out in the woods. However I do not have any fleas or ticks that are on my pets that seems to be working very well

He's just the medicine for both of my pets I live out in the woods. However I do not have any fleas or ticks that are on my pets that seems to be working very well. They have been on it for several years without any issues.