Dede
Forgot to include that we've never had a dog with heart worm and we use only natural peppermint or lavender castile shampoo on our dogs. Two years ago, we took them to a dog play event with some friends and their dogs so we brushed some essential oils into their coats just in case. No fleas, ticks or pests of any kind on all 6 of our fuzzies when we came home and checked each one.