It’s really hard to say. I’ve found two research papers showing average fatal level is 9 and 9.5, but it hugely depends on your tolerance. Someone with no tolerance could overdose at 2 and there are cases of non-users overdosing from a single 50 or 100 mcg patch, which is why they only prescribe those to people that already have a high tolerance. If you’re a heavy user, you may be able to survive much higher levels. Before powdered fentanyl from China via Mexico became readily available and cheap, a 100 mcg patch sold on the street for about $75, so he had about $450 of fentanyl in him. Without knowing his past usage history, there is no way to know, but it was a massive amount of fentanyl no matter what.
Wasn't it something like 4x the lethal dose?
It’s really hard to say. I’ve found two research papers showing average fatal level is 9 and 9.5, but it hugely depends on your tolerance. Someone with no tolerance could overdose at 2 and there are cases of non-users overdosing from a single 50 or 100 mcg patch, which is why they only prescribe those to people that already have a high tolerance. If you’re a heavy user, you may be able to survive much higher levels. Before powdered fentanyl from China via Mexico became readily available and cheap, a 100 mcg patch sold on the street for about $75, so he had about $450 of fentanyl in him. Without knowing his past usage history, there is no way to know, but it was a massive amount of fentanyl no matter what.