Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Good product

I take NAC to combat addiction. Studies have been done, and so far results are good that NAC helps to reduce cravings for addictions like gambling and alcoholism. Personally, I believe this product does help. Swanson is a good brand. I've also taken GNC's NAC, however,their pills stink horribly. Very smelly, and occasionally they upset my stomach.