Not all dog owners choose to use preventative heartworm medicine on their dog. Heartworm medications can create severe side effects in some cases. These side effects occur because manufacturers of the drug use different formulas in their preventatives.
Dog owners that live in colder climates, such as Canada and the Northern states of the U.S may choose to avoid heartworm preventatives entirely. These cold environments don’t allow for many mosquitos to breed and the risk of being bitten is low.
In these cold weather circumstances, most owners feel that dosing their dog with an unproven toxic chemical is not the best choice for their pet’s health. Therefore, abstaining from the preventative measure is a prudent move. However, these owners still need to take their dog’s for a blood test once a year to ensure their pet has no sign of heartworm infection.
The top reason for most dog owners avoiding heartworm preventative measures is because heartworm takes a long time to spread to a critical stage. Therefore, these owners feel that regular testing of their dog is a better strategy to lacing their skin with potentially toxic chemicals.
Some heartworm preventatives experienced recalls from their manufacturer’s due to dangerous side effects and fatalities in dogs after administration. Due to the history of these medications, it’s easy to see why some owners would be fearful of medicating their dog.
Due to the side effects of preventative medicines, some owners choose to take the matter into their own hands and use holistic or natural means of controlling potential heartworm infections, such as pet-friendly mosquito repellant.