I was told by a vet tech to apply the dogs frontline plus every 3 weeks, that 4 weeks is too long even though that is what the directions state. The dogs have had fleas so bad (they visit my parents house which is infested with cat fleas) that I have used both the drops and the spray at the same time with no ill effects, I reduce the amount of the drop dose to about half, and use the proper equivalent amount in the spray and it seems to be quite effective. My dogs are 7 lbs and 16 lbs. I think the spray is even more effective than the drops, but the combo has really worked for me. Just be careful you don't use too much at once.
answered 10 months ago
2out of 2found this answer helpful.