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Sentinel Spectrum

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2. We verify your prescription and ship your order!
Starts $72.94 $49.60 
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Product Info
How to Use
Customer Reviews
Product Info

What is Sentinel Spectrum?

Simplify your dog's heartworm and flea protection with Sentinel Spectrum, the only beef-flavored chewable to protect against 6 parasites. Given monthly, Sentinel Spectrum prevents heartworms and prevents and controls fleas. Each chew also treats and controls whipworms, hookworms, roundworms and tapeworms. Sentinel Spectrum requires a prescription from your veterinarian.


Dogs & Puppies (6+ weeks of age, weighing 2+ lbs)


  • Dogs love the delicious beef-flavored chewable
  • Prevents heartworms
  • Prevents and controls fleas
  • Treats and controls common intestinal parasites (whipworms, hookworms, roundworms and tapeworms)
  • Simple once-a-month administration
  • No messy residue to worry about, unlike spot-on treatments

How does Sentinel Spectrum work?

Milbemycin oxime, lufenuron, and praziquantel are the active ingredients in Sentinel Spectrum, which work to control fleas, major intestinal worms, and heartworms. Sentinel Spectrum contains an insect growth regulator (IGR), which kills flea eggs thus preventing them from hatching into adult fleas. Sentinel may be given along with Capstar, which treats flea infestation.


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 offspring (microfilariae). These reactions are presumably caused by the release of protein from dead or dying offspring. Do not use in puppies less than six weeks of age. Do not use in dogs or puppies weighing under two pounds. The safety of Sentinel Spectrum has not been evaluated in dogs used for breeding or in lactating females.

Brand Name:

Sentinel Spectrum

What is the most important thing I should know about Sentinel Spectrum?

Sentinel Spectrum is indicated for the prevention of heartworm disease caused by Dirofilaria immitis, for the prevention and control of flea populations, and for the treatment and control of adult roundworm, adult hookworm, adult whipworm, and adult tapeworm infections in dogs and puppies two pounds of body weight or greater and six weeks of age and older. The active ingredients are Milbemycin oxime, lufenuron, and praziquantel.

What should I discuss with my veterinarian before giving Sentinel Spectrum to my pet?

Sentinel Spectrum requires a prescription from your veterinarian. Ask your veterinarian if Sentinel Spectrum is right for your pet. 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. Sentinel Spectrum is not effective against adult D. immitis.

How should Sentinel Spectrum be given?

Sentinel Spectrum should be administered orally, once every month with dosing based on your dog's weight. For heartworm prevention, give once monthly for at least 6 months after exposure to mosquitoes. Sentinel Spectrum should be given once a month, every month of the year. Preferably, Sentinel Spectrum should be given on the same date each month. For dogs and puppies 2-8 lbs, give 1 chewable every month (Orange box). For dogs 8.1-25 lbs, give 1 chewable every month (Green box). For dogs 25.1-50 lbs, give 1 chewable every month (Yellow box). For dogs 50.1-100 lbs lbs, give 1 chewable every month (Blue box). For dogs over 100 lbs, give the appropriate combination of chewables.

To ensure complete absorption, always give Sentinel Spectrum chewables to dogs either with or immediately after a normal meal. Food is essential for proper absorption of the product into the bloodstream. Most dogs like the taste of the Sentinel Spectrum chewable and will accept the chewable readily as a treat. The chewables should be administered in a manner that encourages the dog to chew, rather than to swallow the medication without chewing. The chewables may be broken into pieces and fed to dogs that normally swallow treats whole.

Sentinel Spectrum should be administered at monthly intervals beginning within 1 month of the dogs first seasonal exposure to mosquitoes and continuing until at least 6 months after the dogs 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.

What are the potential side effects of Sentinel Spectrum?

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.

What happens if I miss giving a dose of Sentinel Spectrum?

Consult your veterinarian.

What happens if I overdose my pet on Sentinel Spectrum?

Consult your veterinarian in the event of a suspected overdose of Sentinel Spectrum.

What should I avoid while giving Sentinel Spectrum to my pet?

Do not give Sentinel Spectrum to your pet if already giving an alternate heartworm medication.

What other drugs will affect Sentinel Spectrum?

While Sentinel is safe to use in dogs at risk for MDRI-allele mutation (Australian Shepherds, Collies, Shelties, etc.), unless tested normal, caution is advised if your pet is also being given amiodarone (Cordarone), azole antifungals such as ketoconazole, carvedilol (Coreg), cyclosporine (Atopica), diltiazem (Cardizem), erythromycin (Ery-Tabs) or clarithromycin (Biaxin), quinidine, spironolactone (Aldactone), tamoxifen, and verapamil (Calan).

How to Use

Sentinel Spectrum Directions:

  • Give Sentinel Spectrum once a month on the same day of each month year-round.
  • For proper digestion, administer Sentinel Spectrum to your dog immediately after or with a normal meal.
  • Sentinel Spectrum is for use in dogs only. Do not give to cats.
  • Watch your dog closely following dosing to be sure the entire dose has been swallowed.

Do not remove Sentinel Spectrum from the wrapper until ready to give to your dog.

Dogs & Puppies: (6+ weeks of age, weighing 2+ lbs)
2-8 lbs
Give 1 chewable every month (Orange box)
8.1-25 lbs
Give 1 chewable every month (Green box)
25.1-50 lbs
Give 1 chewable every month (Yellow box)
50.1-100 lbs
Give 1 chewable every month (Blue box)
Dogs over 100 lbs
Give the appropriate combination of chewables
Do not use!
Do not use!

Store in a dry place at controlled room temperature, between 59° and 77°F (15-25°C).


Sentinel Spectrum Ingredients:

Sentinel Spectrum Orange for Dogs 2-8 lbs:
Active Ingredient (per chewable tablet)
Milbemycin Oxime
2.3 mg
46 mg
22.8 mg
Sentinel Spectrum Green for Dogs 8.1-25 lbs:
Active Ingredient (per chewable tablet)
Milbemycin Oxime
5.75 mg
115 mg
57 mg
Sentinel Spectrum Yellow for Dogs 25.1-50 lbs:
Active Ingredient (per chewable tablet)
Milbemycin Oxime
11.5 mg
230 mg
114 mg
Sentinel Spectrum Blue for Dogs 50.1-100 lbs:
Active Ingredient (per chewable tablet)
Milbemycin Oxime
23 mg
460 mg
228 mg
Customer Reviews
Sentinel Spectrum is rated 4.2 out of 5 by 39.
Rated 5 out of 5 by from Satisfied with product We started using this product through our vet's recommendation as we were visiting an area with high risks (going from the desert to the south) and needed such prevention for all three of our dogs. We decided to go back and move to the area we visited and our vet's office let us know about this website. Now our costs are dramatically reduced as the website offers far better pricing and it's a simple fax to our vet to process the order. We ordered 12 so they will be covered for 4 months total (1 each for all 3) and we'll be ordering again before they run out. This is our 3rd month using this product so far and no issues. We have one that's 8 lbs, one that's 15 lbs, and one that's 19 lbs.
Date published: 2017-01-17
Rated 4 out of 5 by from Using Sentinel Spectrum: So far I have had pretty good success using this product. Been using it a little over a year as I use it both of my Yorkies Madilyn Rose 14 lbs 6 yrs. old . & Marleigh Belle 10 lbs.2 yrs. old.
Date published: 2017-01-15
Rated 5 out of 5 by from Great Product I have been using this product for 10 months and took my bog to the vet for varies thing. They always check her for flees and other things she is always clean.
Date published: 2017-01-13
Rated 5 out of 5 by from I really like it, I just hate the price it's so expensive!
Date published: 2017-01-09
Rated 5 out of 5 by from Great product! As a registered veterinary technician, I need my dog to be well protected. I switched from Trifexis because the price got so high. I have a small dog, so I didn't really need tick protection anyway. This is a great product and provides peace of mind.
Date published: 2016-12-06
Rated 5 out of 5 by from So far pretty good Not the best for flea prevention but with 5 dogs 4 cats we are bound to have fleas. Oldest is 15 and has tested neg all his life for all worms.
Date published: 2016-11-18
Rated 5 out of 5 by from Healthy dog Changed from trifexis as it was so expensive and we really dont need tick protection on a regular basis. But this gives him all the heartworm/worm flea protection you could ask for. My vet said a topical tick application can be used with it if needed. He has tested negative for heartworms every time so its doin its job!
Date published: 2016-11-14
Rated 5 out of 5 by from So easy to give to my dog!!! There is nothing easier or more effective than Sentinel Spectrum!!
Date published: 2016-11-13
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My puppy weighs 41lbs. I usually buy a 6 month supply of Spectrum Sentinel for him- do I buy the under 50lbs or above as within 6 months he will most likely be more than 50 lbs? 

Asked by: sarchakra
If your dog is still growing and is going to be over 50 lbs, the 50lbs or above should be fine. Be sure to consult with your veterinarian about any changes first.
Answered by: Ben B
Date published: 2017-03-13

What if my dog weighs more than 100 lbs. Do I need to find a different product?

Asked by: Goat1625
No. Just use a second, proper sized tablet to cover the additional weight over 100 pounds.
Answered by: SuzyCVT
Date published: 2017-02-26

Can I use this with Simparica flea and tick.  I need tick prevention also and the topical drives my dog nuts.

Asked by: Amy3211
Yes, you may use Simparica with Sentinel Spectrum as the flea control works entirely differently...Sentinel Spectrum only sterilizes fleas while the Simparica kills them and ticks.
Answered by: SuzyCVT
Date published: 2016-12-13

If I purchase the sentinel spectrum can you still use the rebates from sentinel?

Asked by: karsue
Please contact our sales department for more information on pricing and special discounts
Answered by: S Duesler PharmD MBA
Date published: 2016-11-17

Do you give discounts to Novartis employees?

Asked by: joer
Please contact our sales department for pricing and special offers.
Answered by: S Duesler PharmD MBA
Date published: 2016-11-17

Can I use this and comfort is at the same time?

Asked by: Nikki
Yes, it is safe to use Sentinal Spectrum and Comfortis at the same time as one only sterilizes fleas and the other kills fleas outright.
Answered by: SuzyCVT
Date published: 2016-11-01

I was giving my dogs their medicine and and one of them stole one from another dog. So he actually had 2 chewables. Will this hurt him?

Asked by: Pittie mom
Your dog should be fine; however, make sure to monitor your dog over the next few days for any side effects or changes in behavior. Contact your veterinarian immediately if your dog starts acting strange or seems sick.
Answered by: Christine
Date published: 2016-10-18

Can you use flea and tick shampoo with this medication?

Asked by: Shirley65
Yes you can!
Answered by: Christine
Date published: 2016-10-05
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