See the Best Heart & Intestinal Wormers in 2019 as rated by Australians on ProductReview.com.au.

Sick dog

I gave this to my Aussie Bulldog for the first time last night and she has been vomiting ever since. She keeps arching her back like she has a sore tummy and is lethargic. So annoyed as this cost $140 for 6 months worth and we won't be using it again.

Purchased in August 2019 for $139.00.

Side Effects Short-term illness
Pet TypeDog

Terrific product and well-priced

I have been using this product on my Maltese Poodle for a few years now and never had an issue. She has never had a negative reaction to the product and gobbles it up each month just like a treat! Gives me peace of mind that she is protected from nasties.

Purchased in February 2019 for $80.00.

Value for Money
Ease of Use
Side Effects None
Pet TypeDog

Effective but expensive

Our small dog has had no issues since using this product. We have to wrap the pill in ice-cream for him to eat it though and this is OK as its once a month. The RRP on this is outrageous and with an automated on-line search I can still get it for around $13 per pill buying packs of 6 or 9. The dog does still get the occasional Tick and we have to inspect him every day basically for Ticks. No issues with Spectrum other than the cost.

Purchased in March 2018.

Value for Money
Ease of Use
Side Effects None
Pet TypeDog

This is an awful medicine that made both our dogs sick

Our bigger dog 50 lbs is very lethargic and not acting her normal self. Our little dog 10lbs has had bad diarrhea and extremely lethargic. Neither dog is acting normal.

Purchased in May 2019.

Value for Money
Ease of Use
Side Effects Short-term illness
Pet TypeDog

dosn' t work on fleas

Maybe it works on worms but didn't seem to have any effect on fleas. It says on the packet it will not kill fleas but prevents re infection. Both my dogs had fleas during treatments. "did the dogs pick the fleas up from outside"? well the fleas today were tiny so seemed to be new borns. I am going to change products but in all fairness we have people visiting us everyday with their two dogs and have cats so maybe impossible to control xx

Purchased in August 2018.

Value for Money
Ease of Use
Side Effects None
Pet TypeDog

Excellent Product

I have used Sentinel Spectrum for many years and have seen zero side affects.
The product works well and we not had fleas or worms.
I highly recommend it from puppy through to an aged dog.

Purchased in December 2003.

Value for Money
Ease of Use
Side Effects None
Pet TypeDog

Never use this for your loving dog!

I gave this to my dog on December 31st because I was off of work and like to monitor a reaction, of any. From this day on, and it is now Jan 8, my dog has rarely had anything to eat. One side affect of this drug is anorexia. I have never experienced this issue with my dog and would appreciate further studies to determine if this drug is safe as I really dislike the idea of having further vetenary bills on top of what this medication costs. So, the manufacturer needs to put out a warning to dog owners and veterinarians that this is a big problem.

Been using this for years its amazing!

Have used this product for years on my boxers, works AMAZING!!

For people that are rating this product down because their dog has had seizures.. Your dog would have had an underlying issue beforehand. As the product states on the packet you should be consulting with your Vet to make sure your dog does not have heartworm before using the preventative medication.
ANDDD if your dog has fleas before using this product it ALSO states it only kills flea larvae and eggs not adult fleas (there are 4 stages of fleas not just eggs and the adult flea)... so if your dog has fleas you actually need to get off your bum and remove them not leave it to a little pill to try and solve your dogs issue for you... seriously people its a preventative medication.

Have always used Sentinel, but no more!

We’ve had our mixed breed on Sentinel his whole life (8 yrs), and we are suddenly having a flea problem. He doesn’t have a history of fleas. I don’t know if the formula changed, or what happened, but lately it seems that the Sentinel isn’t even stopping the cycle. If I have to buy a separate pill for fleas, then what is the point to keep buying this?

Side Effects

I gave this product to all my pugs and one had a terrible reaction. The next day he acted lethergic and would not eat. Within 24 hours he was having trouble walking with issues in his rear. After 300.00 at my vets and 3 different meds it took him a whole month to come back. It hit his nervous system hard. I will not take the chance of it hurting my other dogs so will not give to any of my animals again.

Easiest method to avoid Heartworms, Intestinal Worms and Fleas

Feed it to your dog with a full meal just like a treat. My dog would not know what a flea was, and has never had intestinal worms. Easy, quick, fuss and mess-free this is the simplest method to keep your dog Heartworm-free and never know a flea. It is a once-a-month chew, and the dog loves it. The product is highly efficient, and you will never have smelly or sticky fur on the back of their neck again. My Belgian Shepherds have never experienced nasty side-effects and each month they all think that it is "treat time". I have used this product since its introduction to the Market and have never had a problem.

Seizures after single use

My healthy happy 7.5 year old english bulldog started having seizures 8 hours after first dose. 2 months later she is on seizure meds and still suffering. Terrible chemical.

Convenient and effective IF you control adult fleas first

I see some reviewers are frustrated as they expect this product to kill adult fleas, which it does not. The product purpose is to break the breeding cycle: when an adult flea lays eggs, they can't hatch. It's unavoidable that your dog will get fleas from other dogs, fleas jump on from the grass, flea eggs at home will hatch up to a year later. The key is to stop these odd few fleas becoming a plague, this is what you are paying for, and this is why you use it over the long term on dogs that don't have fleas. The worming part is a bonus, and it works well.

So if you have a current flea problem you must kill the adult fleas - most effective method is wash your pet with a Permoxin based product twice a week until all the adult fleas are dead. Inspect your pet thoroughly to find out. Mandatory to treat all bedding with the same chemical, and flea bomb your house too. It's such a chore but there are no shortcuts to eradicating a plague of fleas. With adult fleas now under control, Sentinel Spectrum will help you keep it that way.

brilliant, easy to use

Have used this product for the last 6 months on my puppy, it’s amazing, use every month and he’s never had any problems regarding fleas or ticks. 100% would buy again.

Used for 15 years oldest dog.....

Used on two dogs since pups. One lived until age 15. The 12 year old Havanese is still with us. The loved their monthly treat. Never a flea in 15 years. No health problems whatsoever. We used Sentinel Flavored Tabs.

This made my baby girl not want to eat her food.

I really hate to be negative, but this medicine made my 10 lb morkie not want to eat her food. She was lethargic and has thrown up several times soon after having the medicine. After the first dose she seemed a little lethargic. The last couple of months her reaction has gotten worse after each dose. After reading the reviews I can see it is not just my imagination or just my sweet Lola. I am going to have to throw the rest of my medicine away.

Flea For All

I applied this product on both of my dogs. No side effects were noted. They are both six years old. One is a Jack Russell and the other is a Jack Russell cross
.I consider my dogs small to medium.The heaviest dog weighs approximately 10 kilos, while the other dog ways approximately 6 kilos To save a few dollars, I purchased the dosage recommended for small dogs only. Within 10 minutes, they both discontinued to scratch and gnaw at their hot spots.
It has been just on four weeks since the first dose. Now they are both exhibiting severe flea irritation.
While the product works as described, I have bought other products that were both cheaper and longer lasting. However, I would still recommend Sentinel as an alternative paparticularly if your pets have become resistant to other products.

Convenient and Effective

I have been using this on my 2.5 year old Pomeranian since he was 3 months old and he’s never had fleas, heartworm or worms. He loves the chew and thinks it’s a tasty treat. No side-effects. Thumbs up!


Ever since my German Shorthaired Pointer was 3 moths old she was given Sentinel. At about 4-1/2 months she started having seizures. From that age until she was about 3-1/2she would have 8-12 petite mal seizures a year. Sometimes having cluster seziures (more than 10) in a single week. Ranging from a minimum of 30 minutes until a maximum of 1-1/2 hours. YES a minimum of 30 minutes. My vet diagnosed her as epileptic. I tried tons of different things, I received second opinions and even tried anti seizure medication and a range of different dog foods and vitamins. I recall suggesting my concern several times that sentinel could be causing the seziures. Both vets insisted that it was a safe product and it was extremely unlikely, and they were positive that Sentinel was not causing her epileptic episodes. After a while I gave up and didn't know what to do. Out of desperation I tried one last thing against my Dr's advice and stopped giving my best friend Sentinel and started her on Heart Guard. It is been almost 2 years and she has had NO seziures and lives a completely normal life. I'm sure for some dogs Sentinel is safe but the bottom line is, it was not safe for my dog. Sentinel can cause seziures and don't let anyone tell you otherwise.

Killer Medication

I had a beautiful black-n-chihuahua. She was 2 years and 6 months. She was very playful & sweet. I loved her very much and so did my family. I gave her the medication on Friday morning. She ate that night. The next morning she was acting like she didn't feel good. I took her out and she just came back in and layed in her dog bed. Normally, she runs around playing. My vet was closed so I made plans to run her to her vet early Monday morning. She started walking around and drinking some water it seemed she was feeling better. Saturday night she didn't really eat her dinner. She seemed to be weak. I picked her up and starting checking her. I pet her and put her on her pillow on my desk. It was midnight then. She wagged her little tail. 10 minutes later she threw up everywhere's. I cleaned up everything and started looking for emergency vets close to me. I then went to the bathroom to get dressed when I came back my baby was acting like she was having a seizure then she closed her eyes. I kept petting her and crying. She never responded when I said, her name. I picked her up and she didn't respond. She had died I couldn't believe it. It was terrible I missed my fur-baby so much. She was fine till she took this medication. Natural, is the best way to go.

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Questions & Answers

My miniature schnauzer is 4 yrs old and has been on sentinel spectrum every month since the day we got her. But once last yr. She got fleas from the backyard and now its happening again...what can I do to rid her of them?
No answers

Our American Bulldog pup is six months old and weighs about 18kg. Is Sentinel Spectrum blue okay for her?
No answers

My dog Lucy has chewed this chewable correctly every time it has been given to her, but this time she swallowed it! Will it dissolve in her system or come out when she does her business outdoors?
2 answers
Hi Beth, it will just break down in her stomach and be absorbed.Thank you for answering quickly Hilary!


Sentinel Spectrum Orange (Very Small Dog)Sentinel Spectrum Green (Small Dog)Sentinel Spectrum Yellow (Medium Dog)Sentinel Spectrum Blue (Large Dog)
CategoryHeart & Intestinal Wormers and Tick & Flea ControlHeart & Intestinal Wormers and Tick & Flea ControlHeart & Intestinal Wormers and Tick & Flea ControlHeart & Intestinal Wormers and Tick & Flea Control
Application TypeChewableChewableChewableChewable
Pet TypeDogDogDogDog
Reapplication PeriodMonthlyMonthlyMonthlyMonthly
Minimum Pet Age6 weeks6 weeks6 weeks6 weeks
Release dateAug 2007Aug 2007Aug 2007Aug 2007

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