You may have had a recommendation from your vet to start your dog or cat on a regular heartworm preventative. No pet owner wants their animal companion to succumb to a dangerous disease, but do you know why heartworm preventatives are so important?

It only takes one bite

Heartworm is spread in one way only: by the bite of an infected mosquito. So, wherever there are mosquitoes, your dog or cat is at risk. Avoiding areas of heavy infestation and using insect repellents may help reduce the risk of a mosquito feeding on your dog or cat, but it is impossible to provide 100% protection. A single bite from a mosquito carrying heartworm can transmit enough infective larvae to cause heartworm disease.

Treatment for dogs can be dangerous

Once a dog develops heartworm disease, there are treatment options available to your vet. However, these are not without their own risks, and certainly not without expense. The treatment consists of a series of injections to kill off the adult heartworm. As these worms die and decompose, the fragments can potentially block your dog’s blood vessels. Following each injection, your dog will need to be confined, as any exercise will increase the risk of these blockages.

There is no heartworm treatment for cats

Unfortunately, the treatment methods used to eliminate heartworm in dogs cannot be used for cats, which is why prevention is so important. Although cats are not natural hosts for heartworm, once the worms develop, they can make your cat very ill and even cause sudden death. The good news is that with the right care to stabilize symptoms, many cats can recover.

How do heartworm preventatives work?

The name preventative can be slightly misleading - heartworm medications cannot prevent your dog or cat from being infected by heartworms. However, what they can do is kill off the microscopic heartworm larvae known as microfilariae, thus preventing the development of mature worms.

Heartworm medications work by eliminating microfilariae that may have entered your pet’s bloodstream in the 30 days previous. These preventatives have no lasting effect and cannot kill off future infections, so maintaining a regular dosing schedule is extremely important. Preventatives are usually given as a monthly oral or topical dose and are often combined with ingredients to treat other parasites. Products such as Heartgard Plus will also treat other worms, while Advantage Multi or Revolution will also treat fleas, mites and intestinal worms.

Heartgard Plus

Revolution

Advantage Multi