Interceptor  refers to heartworm medication for dogs, as well as an antiparasitic, which exerts its action through the elimination of mites and worms.
It is an FDA approved prevention of heartworm infection in dogs, especially those that are brought on by Dirofilaria immitis . They may also help control and eliminate other worms such as hookworms and whipworms.
Here are more heartworm prevention medication options for dogs.
What’s an Interceptor for dogs and what does it do?
It is recommended for use in dogs and puppies that are over four weeks old and weigh at least two pounds. The best thing about interceptor is that it is considered safe for both pregnant and lactating dogs . They’re available in a palatable tablet, for once a month dosage.
It is indicated as a preventative measure for both dogs and puppies, four weeks old, weighing two pounds and over, and more specifically should be used to prevent the following:
- intestinal ascariasis
Heartworm disease  is caused by Dirofilaria immitis, and it is a severe and fatal condition that can destroy red blood cells, as well as lead to severe shock. The disease progresses slowly and can be present in the dog for almost seven years.
Typically, it starts with a mosquito bite that carries the filaria organism. It then injects larva into the dog’s bloodstream and lodges itself in the pulmonary artery. The inflammatory changes then result in tissue damage in the arteries and the continued proliferation of the heartworm will prevent the flow of blood.
The tissue damage will occur at a much faster rate than the dog’s body will be able to repair it, which creates a variety of blood clots that block the flow of blood even further. To compensate for this, blood is then rerouted to other worm free arteries. This will also favor the leakage of plasma to the extracellular compartment.
The increase of arterial tissue damage and blockage of the blood vessels will eventually lead to an increase in pressure on the vena cava that leads heart failure over time. Your dog’s immune system will also work overtime in order to contain the situation.
Yet another fatal parasitic infection that is caused by Ancylostoma tubaeforme.  These parasites are deadly to puppies, and while they do not invade the heart, they do draw blood from the small intestines of dogs. As a result, a variety of inflammatory reactions as well as the development of anemia significantly impairs the delivery of oxygen to the tissues.
While this condition may not be as deadly as the hookworm or the heartworm disease, it can still pose significant health issues, especially for the younger puppies. The common ascariasis you shall find in dogs is the leonina and the Toxocara species.
These are the classic parasites  that frequently rob your dog of nutrients that is intended for other purposes. This will then lead to canine malnutrition and an emancipated appearance. They may also present with a pot-bellied appearance and dull coats.
In case this parasite migrates to the lungs, you may find your dog suffering from a critical case of Pneumonia.
Whipworms are found in the large intestines and normally attack the lining of the colon. This will lead to severe irritation which produces a watery and at times even bloody diarrhea. Also, your dog will lose weight and have general debilitation. The most common whipworm is the Trichuris vulpis. 
Mange is an inflammatory skin disease that is typically characterized by very intense itching in dogs.  It can be caused by either Demodex Canis or Sarcoptes scabiei which are the primary causative agents in sarcoptic mange.
Benefits of an Interceptor
Interceptor for dogs is a constructive way to prevent dogs and pups from falling victim to heartworm disease. It is also beneficial in controlling active intestinal parasites such as roundworms, hookworms, and whipworms.
Protects against heartworm and intestinal parasites
Since it is heartworm medication used in dogs, it will help prevent the growth and development of the notorious Dirofilaria immitis, making it unable to produce the adverse effects in the dog’s body – especially the heart and arteries.
It is also an effective treatment against hookworms, whipworms, and ascarids. It also provides health benefits which will ultimately lead to better absorption of nutrients, enhanced elimination of waste, as well as improved oxygenation.
Controls demodectic and sarcoptic mange
Interceptors also help to bring relief to dogs that suffer from these infections. It merely means that if you use the interceptor, your dog will not suffer from swelling, itching, and pain anymore.
It is a chewable tablet, which makes it easy to administer to your dog. You will, therefore, be more confident that your precious puppy is receiving the required treatment against all of the above diseases. It is also given once a month, so, you do not need to keep reminding yourself about the next dosage. Simply mark the same day on the calendar, and you are good to go.
Promotes optimal growth of puppies
These parasitic diseases affect the development of puppies. By giving them the interceptor medicine, you guard them against such diseases that hinder their growth, hence giving them an opportunity to develop normally.
How does an Interceptor work?
Interceptor contains an active ingredient known as Milbemycin Oxime , which is a chemical belonging to the broad spectrum of antiparasitic agents.
This chemical prevents the transmission of signals along the various muscle cells and neurons that are susceptible to parasites. It works by enhancing the activity of the glutamate where the muscle cells and nerves commonly surface.
Because the electrical signals are no longer in transmission, the parasites will eventually die.
Struggling with fleas? Check out our recommendations for the best flea treatments.
Side effects of Interceptor for dogs
It is generally well received by dogs, but there have been reported cases (although rare) of the following side effects:
- glassy eyes
- increased phlegm production, and
- loss of appetite.
In some seldom instances, dogs can develop adverse reactions that can be life-threatening, such as:
- nervous system damage
- low blood pressure
- respiratory failure, and
Things you should know before administering
Interceptor can be used on both dogs and cats as heartworm medication, is FDA approved and available only with a prescription.
It comes in 4 color and dosage variants, namely:
- Brown – This has 2.3mg of Milbemycin oxime and its given to dogs that weigh between 2-10 pounds.
- Green – Has 5.75 mg of Milbemycin Oxime. Ideal for dogs that weigh 11-25 pounds.
- Yellow – has 11.5 mg of Milbemycin Oxime. Ideal for dogs weighing 26-50 pounds.
- White – has 23 mg of Milbemycin Oxime. Suitable for dogs weighing 51-100 pounds.
How to give your dog an Interceptor
This medication is given once a month. You will need to take the accurate weight of your pooch so that you can choose the right color and dosage according to his size. Ensure to come up with one specific day each month, e.g. the 5th of every month, and do not forget. In case you forget, however, just give it when you remember, and DO NOT double dose.
If you only want to give it occasionally, then you must dose 30 days after exposure to mosquitoes.
You need to supervise the dog while he takes the drug, to ensure he swallows all of it. The good thing about it is that most dogs find it favorable. You can also crush it and mix it with dog food.
In case of an overdose, ensure to consult your veterinarian immediately.
What the vet needs to know before prescribing Interceptor
You need to let your vet know if your dog is allergic to Milbemycin oxime, or any other form of canine medication and supplements.
Additional medical related reads:
- Novox for hip dysplasia or osteoarthritis
- Methocarbamol for muscle twitches.
- Hydroxyzine for allergic reactions.
- Metacam for osteoarthritis or painful joints.
- Atopica for chronic itchiness and skin allergies.
- Fluoxetine for canine depression and OCD.
- Simparica for tick and flea control.
- Benadryl for allergies.
- Previcox for osteoarthritis.
- Proin for urinary incontinence in dogs.
- Interceptor – PetMD
- Vieira, Ana Luísa et al. “Prevalence of canine heartworm (Dirofilaria immitis) disease in dogs” Parasite (Paris, France) vol. 21 (2014): 5.
- Interceptor Heartworm Preventative Treatment for Dogs – VetInfo
- “Diagnosis Of Heartworm Disease In Dogs” Canadian journal of comparative medicine and veterinary science vol. 21,12 (1957): 420-1.
- “Hookworms of dogs and cats.” U.P. Kalkofen. November 1987
- Seah, S K et al. “Dogs and intestinal parasites: a public health problem” Canadian Medical Association journal vol. 112,10 (1975): 1191-4.
- “Trichuris Trichiura (Whipworm, Roundworm)” Avinash Viswanath. Mollie Williams. October 2018
- “Some effects of sarcoptic mange on dogs.” L.G. Arlian. M.S. Morgan. C.M. Rapp. D.L. Vyszenski-Moher. October 1995
- Milbemycin oxime – PubMed