I don't use the tincture, we have the dried herbal mix. Morgan's quite happy to have it (1 scoopful) on his kibble breakfast. There has certainly been a reduction in the number of ticks, and no fleas at all, so we'll carry on using it. We also give him garlic every couple of days and use calendula oil (from BADA) for our walks in the woods so I'm not really sure which is being the most effective, but at one stage we were getting up to 6-8 ticks a day
now it's down to only 1-2 of the blighters every couple of days or so.