Gosh, I would keep them on it no matter where you live. All it takes is for one heartworm positive dog or cat to come into your neighborhood and transmit the disease to your pets through a pesky mesquito. If everyone had their pets on heartworm medication it would eventually go away.
We don't have it here, but Ranger is on Interceptor which also controls other worms. I have never had a problem with him on the medication and he has a really sensitive tummy. Good luck! |