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Sentinel

3.1 out of 5 Customer Rating
Star symbol Star symbol Star symbol Star symbol Star symbol (922)
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588 Questions Answered
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Sentinel
12pk Yellow 26-50 lbs Flavor Tabs
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Customer ratings Customer ratings
Overall Rating
Customer ratings4.5 /5
922 reviews
5 Star symbol
740
4 Star symbol
61
3 Star symbol
20
2 Star symbol
22
1 Star symbol
79

Overall effectiveness
4.5
Customer ratings Write a review

1-8 of 922 Reviews
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Author avatar
SybilB
Posted 2 months ago
Posted 2 months ago
Breed Lab
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
1.0
Does Not Work
My lab has intestinal works and has been taking this since December of 2020-!
Helpful?

Author avatar
Rosie1234
Posted 4 months ago
Posted 4 months ago
Breed Mix
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
1.0
Doesn’t kill worms
My dog took this medication and had live roundworms in her poop several days later. I will be trying a different product in the future.
Helpful?

Author avatar
Chloe1202
Posted 6 months ago
Posted 6 months ago
Breed Labrador retriever
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
5.0
Unbelievably Fast Shipping
Just ordered one year supply for my 7 year old Lab. Used to get it elsewhere but PetMeds price was fantastic, shipping in 2 days and Chloe went nuts when the box came because she could smell the giant biscuit inside! Thanks for everything PetMeds.
Thumbs up Would recommend this product
Helpful?

Author avatar
Eileen
Posted 1 year ago
Posted 1 year ago
Breed Labradoodle
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
5.0
Great
I have used Sentinel on all my dogs & never was disappointed! My dogs did great on this product
Thumbs up Would recommend this product
Helpful?

Author avatar
Sherry24
Posted 1 year ago
Posted 1 year ago
Breed Mixed
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Negative heart worm result every year
I have used Sentinel for my dog for the six years I have had him I was able to order a year’s supply for less than the six month supply quote from my vet.
Thumbs up Would recommend this product
Helpful?

Author avatar
Anonymous
Posted 1 year ago
Posted 1 year ago
Breed Longhair Chihuahuas
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
5.0
Sentinel & Negard are the best!
My 3 longhair Chihuahuas have been on Sentinel & Nexgard for several years now. Zero issues with any of the dogs and the preventatives! Just perfect results! 1800PetMeds went above and beyond to fix the issue with the vet I was currently going to NOT cooperating with Petmeds! That vet wanted me to buy THEIR meds at a ridiculously marked up price! Thanks 1800PetMeds for the excellent experience with you guys. I will be a life long customer! You simple CAN NOT beat the prices!
Thumbs up Would recommend this product
Helpful?

Author avatar
IGmom
Posted 1 year ago
Posted 1 year ago
Breed Italian Greyhound
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
5.0
Works best for my dog
I’ve tried other medications for fleas/parasites that caused vomiting with blood in my dog. I went back to Sentinel because it’s combined with a heart worm preventative. The topical flea meds aren’t great for my dog as he has short hair, no fat to absorb it.
Review photo
Thumbs up Would recommend this product
Helpful?

Author avatar
RJWilb
Posted 1 year ago
Posted 1 year ago
Breed Border Collie
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
5.0
Recommend!
Our Vet recommends Sentinel for heart worm prevention. Our Border Collie has never had a problem taking it and always gets a clean bill of health from the Vet each year.
Review photo
Thumbs up Would recommend this product
Helpful?

1-8 of 922 Reviews
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What is Sentinel?

Sentinel is the only monthly oral preventive that guards against heartworms, adult roundworms, adult hookworms, whipworms, and prevents the development of flea eggs. Sentinel requires a prescription from your veterinarian.

For:

Dogs and Puppies (4+ weeks of age, weighing 2+ lbs)

Benefits:

  • Comes in palatable flavored tabs
  • Easy to administer just once a month

How does Sentinel work?

Milbemycin oxime eliminates the tissue stage of heartworm larvae and the adult stage of hookworm, roundworm, and whipworm infestations. Lufenuron, the other active ingredient, is an insect development inhibitor that breaks the flea life cycle by inhibiting egg development. Lufenuron prevents most flea eggs from hatching or maturing into adults and thus prevents and controls flea populations by breaking the life cycle.

Cautions:

Side effects are rare, though some pets may exhibit vomiting, depression, drowsiness, itching, hives, loss of appetite, diarrhea, or seizures, hypersalivation, and weakness. If these or other symptoms develop contact your veterinarian. It's important to maintain good personal hygiene, since humans can contract hookworms and roundworms. It's also important to eliminate fleas and to not feed your pet rodents or uncooked meat or fish. To prevent re-infection, clean up stools on a daily basis. Consult your veterinarian for pregnant or lactating dogs.

Brand Name:

Sentinel (Merck)

Generic Name:

Milbemycin Oxime (mil-beh-my-sin ox-eem) and Lufenuron (lew-fen-your-on)

What is the most important information I should know about Sentinel?

Sentinel is a prescription medication FDA-approved for use in dogs. Sentinel is available as artificial beef flavored (derived from pork and soy protein) chewable tablets. This medication should be given once a month year-round.

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

Tell your veterinarian if your pet has ever had an allergic reaction to the medication.

How should Sentinel be given?

Give Sentinel exactly as directed by your veterinarian. If you do not understand the directions ask your pharmacist or veterinarian to explain them to you. The usual dose of Sentinel for dogs 2 to 10 pounds is 1 Flavor Tab every month (Brown Box), 11 to 25 pounds is 1 Flavor Tab every month (Green Box), 26 to 50 pounds is 1 Flavor Tab every month (Yellow Box) and 51 to 100 pounds is 1 Flavor Tab every month (White Box). For dogs over 100 pounds give the appropriate combination of tablets. To ensure adequate absorption, always administer Sentinel to dogs immediately after or in conjunction with a normal meal. Heartworm testing should be performed prior to the start of prevention therapy. If your pet is off Sentinel for 6 months or less, re-start the medication and test after 6 months since microfilaria, that take 6 months to mature, will result in a positive test result. Store Sentinel in a dry place at controlled room temperature, between 59-77F (15-25 C). Do not remove the tablet from its wrapper until ready to give the medicine. Keep this medication away from children and pets. Consult your veterinarian for pregnant or lactating dogs.

What are the possible side effects of Sentinel?

Side effects of Sentinel are rare although some pets may exhibit vomiting, depression, drowsiness, itching, hives, loss of appetite, diarrhea, or seizures, hypersalivation, and weakness. If these or other symptoms develop contact your veterinarian.

What happens if I miss giving a dose of Sentinel?

If a dose is missed and a 30-day interval between dosing is exceeded, administer Sentinel immediately and resume the monthly dosing schedule. If Sentinel replaces daily diethylcarbamazine (DEC) for heartworm prevention, the first dose must be given within 30 days after the last dose of DEC.

What happens if I overdose my pet on Sentinel?

Contact your veterinarian immediately.

What should I avoid while giving Sentinel to my pet?

Because humans can contract hookworms and roundworms from pets, it is important to maintain good personal hygiene. It is also important to eliminate fleas on your pet and in the household.

What other drugs will affect Sentinel?

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

Sentinel Directions:

  • Give Sentinel Flavor Tabs once a month on the same day of each month year-round.
  • Sentinel Flavor Tabs 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. If it is not completely swallowed, give one more full recommended dose as soon as possible.
  • To ensure adequate absorption, always administer Sentinel to dogs immediately after or in conjunction with a normal meal.
  • Sentinel has no effect on adult fleas, but controls flea populations by breaking the flea life cycle at the egg stage.
  • To speed control of flea infestation, products that kill adult fleas like Capstar Flea Treatment Tablets may be used temporarily with Sentinel depending on the severity of the infestation.
  • Treatment may begin at any time of the year.
  • It is important to treat all dogs in the household for fleas. Cats in the same household should be treated with approved products for heartworm prevention for cats.
Tip:

Do not remove Sentinel from its wrapper until ready to give to your pet.

Sentinel Dosage for Dogs/puppies: (4+ weeks of age, weighing 2+ lbs)

Dogs/puppies: (4+ weeks of age, weighing 2+ lbs)
WeightDosage
2-10 lbsGive 1 Flavor Tab every month (Brown Box)
11-25 lbsGive 1 Flavor Tab every month (Green Box)
26-50 lbsGive 1 Flavor Tab every month (Yellow Box)
51-100 lbsGive 1 Flavor Tab every month (White Box)
Over 100 lbsGive combination of Flavor Tabs based on weight
Sentinel Dosage for Cats:
Cats
Do not use!
Sentinel Dosage for Horses:
Horses
Do not use!

Storage:

Should be stored at room temperature between 59° and 77° F.

Sentinel for Dogs Ingredients:

Sentinel Brown for Dogs 2-10 lbs:
Active Ingredient (per tablet)Amount
Milbemycin Oxime2.3 mg
Lufenuron46 mg
Sentinel Green for Dogs 11-25 lbs:
Active Ingredient (per tablet)Amount
Milbemycin Oxime5.75 mg
Lufenuron115 mg
Sentinel Yellow for Dogs 26-50 lbs:
Active Ingredient (per tablet)Amount
Milbemycin Oxime11.5 mg
Lufenuron230 mg
Sentinel White for Dogs 51-100 lbs:
Active Ingredient (per tablet)Amount
Milbemycin Oxime23 mg
Lufenuron460 mg

What is Sentinel?

Sentinel is the only monthly oral preventive that guards against heartworms, adult roundworms, adult hookworms, whipworms, and prevents the development of flea eggs. Sentinel requires a prescription from your veterinarian.

For:

Dogs and Puppies (4+ weeks of age, weighing 2+ lbs)

Benefits:

  • Comes in palatable flavored tabs
  • Easy to administer just once a month

How does Sentinel work?

Milbemycin oxime eliminates the tissue stage of heartworm larvae and the adult stage of hookworm, roundworm, and whipworm infestations. Lufenuron, the other active ingredient, is an insect development inhibitor that breaks the flea life cycle by inhibiting egg development. Lufenuron prevents most flea eggs from hatching or maturing into adults and thus prevents and controls flea populations by breaking the life cycle.

Cautions:

Side effects are rare, though some pets may exhibit vomiting, depression, drowsiness, itching, hives, loss of appetite, diarrhea, or seizures, hypersalivation, and weakness. If these or other symptoms develop contact your veterinarian. It's important to maintain good personal hygiene, since humans can contract hookworms and roundworms. It's also important to eliminate fleas and to not feed your pet rodents or uncooked meat or fish. To prevent re-infection, clean up stools on a daily basis. Consult your veterinarian for pregnant or lactating dogs.

Brand Name:

Sentinel (Merck)

Generic Name:

Milbemycin Oxime (mil-beh-my-sin ox-eem) and Lufenuron (lew-fen-your-on)

What is the most important information I should know about Sentinel?

Sentinel is a prescription medication FDA-approved for use in dogs. Sentinel is available as artificial beef flavored (derived from pork and soy protein) chewable tablets. This medication should be given once a month year-round.

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

Tell your veterinarian if your pet has ever had an allergic reaction to the medication.

How should Sentinel be given?

Give Sentinel exactly as directed by your veterinarian. If you do not understand the directions ask your pharmacist or veterinarian to explain them to you. The usual dose of Sentinel for dogs 2 to 10 pounds is 1 Flavor Tab every month (Brown Box), 11 to 25 pounds is 1 Flavor Tab every month (Green Box), 26 to 50 pounds is 1 Flavor Tab every month (Yellow Box) and 51 to 100 pounds is 1 Flavor Tab every month (White Box). For dogs over 100 pounds give the appropriate combination of tablets. To ensure adequate absorption, always administer Sentinel to dogs immediately after or in conjunction with a normal meal. Heartworm testing should be performed prior to the start of prevention therapy. If your pet is off Sentinel for 6 months or less, re-start the medication and test after 6 months since microfilaria, that take 6 months to mature, will result in a positive test result. Store Sentinel in a dry place at controlled room temperature, between 59-77F (15-25 C). Do not remove the tablet from its wrapper until ready to give the medicine. Keep this medication away from children and pets. Consult your veterinarian for pregnant or lactating dogs.

What are the possible side effects of Sentinel?

Side effects of Sentinel are rare although some pets may exhibit vomiting, depression, drowsiness, itching, hives, loss of appetite, diarrhea, or seizures, hypersalivation, and weakness. If these or other symptoms develop contact your veterinarian.

What happens if I miss giving a dose of Sentinel?

If a dose is missed and a 30-day interval between dosing is exceeded, administer Sentinel immediately and resume the monthly dosing schedule. If Sentinel replaces daily diethylcarbamazine (DEC) for heartworm prevention, the first dose must be given within 30 days after the last dose of DEC.

What happens if I overdose my pet on Sentinel?

Contact your veterinarian immediately.

What should I avoid while giving Sentinel to my pet?

Because humans can contract hookworms and roundworms from pets, it is important to maintain good personal hygiene. It is also important to eliminate fleas on your pet and in the household.

What other drugs will affect Sentinel?

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

Sentinel Directions:

  • Give Sentinel Flavor Tabs once a month on the same day of each month year-round.
  • Sentinel Flavor Tabs 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. If it is not completely swallowed, give one more full recommended dose as soon as possible.
  • To ensure adequate absorption, always administer Sentinel to dogs immediately after or in conjunction with a normal meal.
  • Sentinel has no effect on adult fleas, but controls flea populations by breaking the flea life cycle at the egg stage.
  • To speed control of flea infestation, products that kill adult fleas like Capstar Flea Treatment Tablets may be used temporarily with Sentinel depending on the severity of the infestation.
  • Treatment may begin at any time of the year.
  • It is important to treat all dogs in the household for fleas. Cats in the same household should be treated with approved products for heartworm prevention for cats.
Tip:

Do not remove Sentinel from its wrapper until ready to give to your pet.

Sentinel Dosage for Dogs/puppies: (4+ weeks of age, weighing 2+ lbs)

Dogs/puppies: (4+ weeks of age, weighing 2+ lbs)
WeightDosage
2-10 lbsGive 1 Flavor Tab every month (Brown Box)
11-25 lbsGive 1 Flavor Tab every month (Green Box)
26-50 lbsGive 1 Flavor Tab every month (Yellow Box)
51-100 lbsGive 1 Flavor Tab every month (White Box)
Over 100 lbsGive combination of Flavor Tabs based on weight
Sentinel Dosage for Cats:
Cats
Do not use!
Sentinel Dosage for Horses:
Horses
Do not use!

Storage:

Should be stored at room temperature between 59° and 77° F.

Sentinel for Dogs Ingredients:

Sentinel Brown for Dogs 2-10 lbs:
Active Ingredient (per tablet)Amount
Milbemycin Oxime2.3 mg
Lufenuron46 mg
Sentinel Green for Dogs 11-25 lbs:
Active Ingredient (per tablet)Amount
Milbemycin Oxime5.75 mg
Lufenuron115 mg
Sentinel Yellow for Dogs 26-50 lbs:
Active Ingredient (per tablet)Amount
Milbemycin Oxime11.5 mg
Lufenuron230 mg
Sentinel White for Dogs 51-100 lbs:
Active Ingredient (per tablet)Amount
Milbemycin Oxime23 mg
Lufenuron460 mg
Customer ratings Customer ratings
Overall Rating
Customer ratings4.5 /5
922 reviews
5 Star symbol
740
4 Star symbol
61
3 Star symbol
20
2 Star symbol
22
1 Star symbol
79

Overall effectiveness
4.5
Customer ratings Write a review

1-8 of 922 Reviews
Most Recent
Most Recent Highest to Lowest Rating Lowest to Highest Rating Most Helpful
Select Filters
Active Filters
No filter selected yet.

Author avatar
SybilB
Posted 2 months ago
Posted 2 months ago
Breed Lab
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
1.0
Does Not Work
My lab has intestinal works and has been taking this since December of 2020-!
Helpful?

Author avatar
Rosie1234
Posted 4 months ago
Posted 4 months ago
Breed Mix
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
1.0
Doesn’t kill worms
My dog took this medication and had live roundworms in her poop several days later. I will be trying a different product in the future.
Helpful?

Author avatar
Chloe1202
Posted 6 months ago
Posted 6 months ago
Breed Labrador retriever
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
5.0
Unbelievably Fast Shipping
Just ordered one year supply for my 7 year old Lab. Used to get it elsewhere but PetMeds price was fantastic, shipping in 2 days and Chloe went nuts when the box came because she could smell the giant biscuit inside! Thanks for everything PetMeds.
Thumbs up Would recommend this product
Helpful?

Author avatar
Eileen
Posted 1 year ago
Posted 1 year ago
Breed Labradoodle
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
5.0
Great
I have used Sentinel on all my dogs & never was disappointed! My dogs did great on this product
Thumbs up Would recommend this product
Helpful?

Author avatar
Sherry24
Posted 1 year ago
Posted 1 year ago
Breed Mixed
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Negative heart worm result every year
I have used Sentinel for my dog for the six years I have had him I was able to order a year’s supply for less than the six month supply quote from my vet.
Thumbs up Would recommend this product
Helpful?

Author avatar
Anonymous
Posted 1 year ago
Posted 1 year ago
Breed Longhair Chihuahuas
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
5.0
Sentinel & Negard are the best!
My 3 longhair Chihuahuas have been on Sentinel & Nexgard for several years now. Zero issues with any of the dogs and the preventatives! Just perfect results! 1800PetMeds went above and beyond to fix the issue with the vet I was currently going to NOT cooperating with Petmeds! That vet wanted me to buy THEIR meds at a ridiculously marked up price! Thanks 1800PetMeds for the excellent experience with you guys. I will be a life long customer! You simple CAN NOT beat the prices!
Thumbs up Would recommend this product
Helpful?

Author avatar
IGmom
Posted 1 year ago
Posted 1 year ago
Breed Italian Greyhound
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
5.0
Works best for my dog
I’ve tried other medications for fleas/parasites that caused vomiting with blood in my dog. I went back to Sentinel because it’s combined with a heart worm preventative. The topical flea meds aren’t great for my dog as he has short hair, no fat to absorb it.
Review photo
Thumbs up Would recommend this product
Helpful?

Author avatar
RJWilb
Posted 1 year ago
Posted 1 year ago
Breed Border Collie
Rating
Star symbol Star symbol Star symbol Star symbol Star symbol
Overall effectiveness
5.0
Recommend!
Our Vet recommends Sentinel for heart worm prevention. Our Border Collie has never had a problem taking it and always gets a clean bill of health from the Vet each year.
Review photo
Thumbs up Would recommend this product
Helpful?

1-8 of 922 Reviews
Ask a question Ask a question


search questions Search questions
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