Instruct: Classify Amazon reviews into positive or negative sentiment
Query: First Time Flea Med

After I applied it, my pup started scratching like crazy (almost like paranoid scratching) but he seemed fine since he was able to get some rest here and there. What concerned me is that he began biting at his nether region, which resulted in little cuts (he's never done that in the time he's had fleas). Also, when I gave him the commands he has already learned really well, it took many repetitions for him to finally follow them (he stared blankly for a long period of time). In addition, his urine became darker even though he consumed the same amount of water he usually does. The only positive aspect about this product is that I found a few dead fleas 9 hours after use. Still, I won't make the mistake of purchasing this product again. Especially after reading all of the horror stories & realizing that this harmful product does not even have any warning labels for possible side effects, why risk your dog's health? Not worth it at all.