Q. My 9 year old lab has tested positive for heart worms. A feed store owner told me I could use Noromectin (ivermectin) to get rid of them? Is it safe?
DESTINI R. HOLLOWAY, DVM
A. The feed store owner is taking about the "slow kill" method for adult heartworms. This method is the considered an alternate method that has the following disadvantages over the normal immiticide treatment:
1) Takes years (often-times up to 2-4 years) to completely rid heartworms vs immiticide treatment which takes at most 3 months
2) Slowly kills baby worms only in the bloodstream, does not kill adult worms in the heart. Immiticide kills the adult worms that are in the heart directly which is why it is so effective.
3) Higher risk of thromboembolism (clots in the lung artery) than Immiticide treatment.
4) Adult worms will stay in the heart for years and can impede blood flow.
So that is the gist of doing the slow kill method for baby heartworms instead of the fast kill method with Immiticide for adult heartworms. Which is why most veterinarians will recommend the fast kill method as the best choice for your pets care.