It's absolutely nuts in the US. Checking lab results pages of samples sent it, 95-99% of ALL "heroin" samples sent in contain some or all fentanyl. Lots of new users literally have never had real heroin even though they think they have. A number of people I know, despite this, and despite full well knowing they're getting fentadope, keep using it, because addiction is a bitch and you'll do anything to stop withdrawal. A good friend of mine has fallen out and woken up either in an ambulance or just hours later with needle in arm, quite a number of times. Finally got on methadone and has managed to stay on so far.