Instruct: Classify Amazon reviews into positive or negative sentiment
Query: WORTHLESS FLEA TREATMENT

This product is worthless against fleas. I used this flea treatment exactly as the directions stated and got zero results. My dog has as many fleas now as she did before. If you spend one penny for K9 Advantix you will have spent too much. Waste of money! Whats really bad about the whole situation is I'll have to wait 30 days before I can put any other medicine on my poor dog. DON'T BUY,DON'T BUY.