Great question. What you choose to use is completely up to you. I believe pet owners should be able to make educated decisions and have choices that are right for them. Keep in mind, although the marketing of spot-ons states to use it every month, that’s actually considered over-use. The EPA has stated officially after they investigated spot-on products that they should only be used as a final attempt, after everything else has failed, and only as direly needed. Pesticides leave residues in your house dust which continue to effect you and your children and pets. Even small amounts can behave as endocrine disruptors which means hormones and the endocrine system is negatively impacted leading to things like thyroid issues, reproductive problems, PCOS, ADHD, ADD and autism. (The FAQ list is longer, these are just a few.) The President’s Report on Cancer lists pesticide exposure, include home uses on lawns, sprays and pet products, as a leading cause of cancer. Pet products that treat fleas & ticks that are pesticides have no follow up surveillance to link use to long term effects such as cancer, diabetes, thyroid problems and kidney failure. However there is a large body of scientific studies that show these effects in humans from the same pesticides used for other things such as crops.