Hello, I'm Dr. Gregg and I will try to help you out today. Good to hear from Portugal. You are using Frontline, which has been good for flea and tick control for a lot of years. Some people feel that it may not work as well as it used to and have added other medications to it to be sure. One that I currently use, with Frontline, is an oral medication called Nexguard. It has done a very good job keeping fleas and ticks at bay, and I am in a heavy tick area (Michigan, along the shore of the Great Lakes). There are any number of flea/tick medications out there now, that do a good job. The question is what is available to you. Do you have access to online pet suppy companies like Petmedexpress or Foster and Smith?
You are quite welcome. Hopefully your Vet has what you need. If I can be of any further assistance feel free to ask. Good luck, Jan. Dr. Gregg
As I said, good to hear from Portugal