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Over the Counter Heartworm Prevention for Dogs

| Updated September 26, 2017

Heartworms can be life altering and ultimately fatal when they take up residence in a dog. Even a healthy dog is susceptible to heartworms since the parasites are transmitted through mosquitoes. Dogs that live in warmer climates where mosquitoes are more prevalent may be more susceptible. Heartworms can be prevented via over the counter heartworm medicine.

Testing for the Heartworm Parasite

Take your dog to the veterinarian and have him tested for the heartworm parasite prior to giving him the heartworm medicine. This will require a blood test, and you should receive the results immediately. Since heartworm prevention medicines are designed to prevent heartworms rather than treat existing parasites, it will be essential to make sure your dog does not have heartworms. You do not want to unknowingly give your pet heartworm prevention medicine for an extended period while he has worms growing inside of him. If your dog tests positive for heartworms, give him the treatment prescribed by your doctor and have him retested before administering preventative medicine.

Choosing a Medicine

Choose which type of heartworm prevention medicine to give to your dog. Your vet likely offers a few different types and will suggest a brand of heartworm prevention for your dog. Consider your veterinarians' recommendation, price, frequency of administration and combination treatments before making a decision. Feel free to compare prices; online pet medication suppliers can often beat veterinarian prices. Additionally, consider how often you will want to give the medication to your dog. Heartworm prevention is available in daily, monthly and six-month doses. Finally, consider whether you want to use a heartworm prevention that incorporates other treatments such as flea prevention.

Other Considerations

Follow the instructions on the box of heartworm prevention. You must give this medicine in regular prescribed intervals for it to be effective. If you find it difficult to give your dog his heartworm medicine, try hiding it in his food or offering it to him with a treat.

Have your dog retested by your veterinarian each year to make sure that he is heartworm free.