My yorkie is on Heartgard Plus and we haven't had any problems. I agree, always better to be safe. He looks forward to taking it because it is chewable and tastes like a treat to them. He is on the 25 lbs and under dosage and you give them the entire dosage because (I was told by my vet) the medication is all mixed up in the tablet and may not be evenly dispersed throughout it.
Happy Traveling!!!
