This is not true: GHB is addictive, very hard to dose and in combination with the most used 'night life' drug (alcohol) actually toxic and lethal in small doses. It's also known as the 'date rape drug' for this very reason.
Yeah I'm going to call bullshit on that unless you provide a source. The interesting thing about GHB is that it is less toxic in higher doses, but I've never read that it's lethal in low doses.
The girl had previous (voluntary) experience with the drug and managed to lock herself in the toilet before passing out. I found her with with several bruises over her face after we broke down the door. The guy was beaten, robbed and left in a bush and that's were we found him. Because I served both their drinks over the night I knew they didn't consume 'too much' alcohol, the girl claimed she could tell the GHB from both the smell(?) of her drink and effect it had on her.