Topical Products
I prefer these products because they can kill the tick before it bites the dog. There is one product that I HIGHLY recommend: Vectra 3D. This topical product REPELS ticks in addition to killing them. That is not true of most other topical products. Topical products that are available in most retail stores include Advantix and Frontline (two of the most common) but many other less recognizable brands contain the same ingredients and all work well to kill ticks. However, I am not aware that any of these have a “repellency” claim.
Internal Products
Nexgard, Bravecto, Simparica, Credelio are four products that most veterinarians recommend. All work very well at killing ticks. But, remember, they kill only after the tick bites. These manufacturers will tell you that the kill occurs BEFORE the tick has been on the pet long enough for any disease to be transferred from tick to dog. This may indeed be true, but to my knowledge, this has never been proven beyond a shadow of a doubt.
What about cats?
Fagetaboutit. Cat’s groom themselves so much that they don’t allow a tick to attach. That is why there are no tick products for cats. They don’t need them. Although I am sure it has happened somewhere, in over 40 years of practice, I have never seen a tick on a cat.