Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Be Cautious...

This product induced severe memory lapses and black outs. After having tests run by a few doctors, it was determined that this herbal product did, in fact, cause me to experience memory loses, lapses in what memories I did have, and enabled me to do things during what seemed to be a period of 'black-outs.' Be very cautious before buying this, discuss with a physician, first!