Safest Heartworm Prevention

Heartworms are contracted by pets through a mosquito bite. Once the animal has contracted the disease, it can be very severe and also difficult to treat. It is much easier to prevent heartworms than treat them. The following methods represent the safest and most effective ways to prevent heartworm in your pets. Some methods are not recommended for certain types of animals, so consult with your veterinarian to determine which is the safest given your pet's breed, age and health conditions.

  1. Oral Preventatives

    • Oral preventatives include ivermectin or milbemycin oxime. These treatments come in either pill or tablet form and only need to be taken once per month. The veterinarian will prescribe the proper dose based on the weight of your pet. Before taking an oral treatment, the pet should be tested to make sure they do not already have heartworms. Ask your veterinarian about potential side effects. These medications are safe and have low incidence of complications, but if your pet develops a rare side effect it will be important to get it treated right away. Ivermectin should not be administered to collies or collie mixes or dogs less than 6 weeks old, because of a higher rate of complication in those types of dogs. Follow the dosage carefully, as overdoses can have bad effects on your pet.

    Topical Preventatives

    • Topical treatments are liquid medications the owner squeezes onto the pet's back, similar to a monthly flea treatment. The drug comes in small pipettes that are administered each month. This method is generally the safest and easiest to administer for adult dog and cats. Side effects are rare, but watch your animal closely for any change in behavior. These drugs are not recommended for kittens under 8 weeks or puppies under six weeks of age.

    Injectable Preventatives

    • Heartworm injections are only available for dogs. They seem like a more extreme form of prevention, but they are administered on a less frequent basis. Heartworm injections are only given once every six months. Injections require less maintenance, but out of all three treatments, they carry the most risk. Consult with your veterinarian before deciding on this method of prevention.