"It is absolutely fantastic." That's just one of the glowing reviews you can find for a popular body building supplement called Craze.
"I kid you not: The energy and the straight up gangster awesomeness of this was there," said another reviewer.
Those reviews were posted online before a new study claimed that there's a good reason Craze makes you feel so powerful is because it contains a stimulant resembling methamphetamine.
A study by a Harvard Medical School professor said: "We found a potentially dangerous designer drug in three separate lots of Craze, calling it a 'stimulant' and 'addictive.' "
Addiction expert Dr. Charles Sophy commented on the product, "Craze and components within it can make you feel like your omnipotent and you're stronger than you really are or 'I can conquer whatever.' But, because there's no studies, you don't know how much to take and you can be pushing your blood pressure limit and you may have a stroke or a heart attack."
Bodybuilder Rob Riches said he failed a drug test this year following his victory at a bodybuilding contest after using Craze manufactured by Driven Sports. Public records show that an address for Driven Sports comes back to a mailbox at a UPS store.
So, who's behind the sports supplement? A man named Matt Cahill and he lives right down the street from the store.
INSIDE EDITION has learned that Cahill was jailed for two years in 2005 for mail fraud after the death of a teenager who used one of his other dietary supplements
Cahill's company, Driven Sports, denies Craze contains anything resembling methamphetamines and is safe. Driven Sports claims that an analysis conducted by a private lab in Michigan showed the chemical was 'not found' in a sample of Craze."
INSIDE EDITION's Paul Boyd asked a lawyer for Craze, "Can you say, unequivocally, that this product is safe for consumers to use."
The representative replied, "We feel it is safe. We have conducted four double-blinded studies and 177 humans without observing an adverse affects."
But bodybuilder Marc Lobliner, who gave Craze a glowing online review, said he's changed his mind about the product.
Lobliner said, "We're getting it out of the stores right now, and we're going to do the right thing."
Although the maker of Craze said it's safe, Walmart.com and several other retailers have stopped selling it pending an investigation.