don’t buy this stuff to save a few dollars.. as you will be paying a lot more in the end. I am a LVT and I hear stories like this alll the time. PLEASE pass it along that not to buy stuff like this from Walmart, petsmart, petco or the drug store. ONLY professional sources of this type of drug should be used. Even places like pet shed or pet med are to be watched as there have been some issues with online drugs as well such as counterfeit drugs… with labels slapped on them and then sold online as the real thing. So don’t go cheap on your babies.
And if your thinking of using nothing.. remember heartworm, lyme disease and internal parasites can cause just as many health issues as the use of these items.