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Lindsey Veterinary Hospital


2 girls with mask on with their two dogs outside in a field

Preventatives keep your dog safe from heartworm and they also deworm against intestinal parasites like roundworm, whipworm, and hookworm.

Heartworm is spread by mosquitoes and therefore all dogs are at risk in the Okanagan.

Due to our warmer climate in the Okanagan, mosqiuitoes live longer than other areas. This extra time allows the heartworm to complete a portion of it's life cycle in the mosquito and can be spread to next dog bitten. Keep in mind that heartworm is mainly carried by the wild coyote population so exactly how many dog species that are affected is hard to tell. Preventative medicines have caused the number to drop in recent years. We see a decline in people giving the preventatives because of the low number of cases, which over time will cause the number to increase again. The preventatives also deworm for intestinal parasites which is very important as well, especially if children or elderly have contact with your dog. The main areas in Canada affected by heartworm are southern Manitoba, southern Quebec, and the Okanagan. All states in the US now report cases of heartworm.

What signs would I see if my dog had heartworm?

Many dogs infected with heartworms may not show any evidence of infection in the early stages of the disease. Adult heartworms live in the heart and lungs. Initially, dogs tend to develop a cough and experience difficulty breathing. They may exhibit decreased tolerance to exercise, develop fainting episodes and suffer severe weight loss. The severity and onset of signs relate to three things: the number of heartworms present, the duration of the infection and the dog's response.

How often should I test my dog?

We recommend testing only every three years provided that you are diligent with the preventative. Puppies born after October, or new dogs that have just moved here from an unaffected area don't need to be tested their first spring. If you have missed a month or season of preventative, then it is best to test before starting preventative the following year.

Are the preventative medications safe?

Yes, veterinary medications have to undergo strict testing to be approved. Here is a list of the preventatives we recommend, select the one that best suits your dog and your lifestyles: Heartgard: chew tablet monthly. It prevents heartworm, controls hookworm, roundworm and whipworm (intestinal parasites). This is the most basic and least expensive. Spectra Nexgard : chew tablet monthly. It does all that Heartgard does with the added protection of killing ticks and fleas. Recommended if you and your pet like camping/ hiking/ live in rural areas (ticks) or travel to the coast (fleas). Revolution: topical application monthly. It is absorbed into the bloodstream through the skin. Revolution also kills fleas and prevents their eggs from hatching, and controls ear mites, sarcoptic mange, hookworm and roundworm. It does not prevent ticks but the tick will die in 1-3 days.