Table 2:

Physiological sensations identified by PWID as indications of a changing heroin supply

Key Indicator	Exemplar Quote
Strong Rush	Male, 34: Yeah, it’s the rush; it’s almost like a warm, real rush. If you do too much, sometimes it can almost be like a massive rush, and then it’s almost like a panic state.
Strong Rush	Male, 36: Fentanyl hits you so hard. There’s a fear associated with it.
Tingly	Male, 36: The ‘pins and needles’ doesn’t ever hurt for me. It’s more just like a tingly sensation in my head.
Sedation	Male, 33: The first time, I’d just been injecting about two or three months and I did this little sprinkle of fentanyl and it just about put me out [made me overdose]. And I told you I’ve never nodded out on dope [heroin without fentanyl].
Heavy sedation	Male, 33: I’m seeing people shoot up and they’re fucking drooling. I see people standing on their tip-toes and just drooling. I don’t even see how they’re not falling over; 10–20 minutes just standing there. Then, they finally snap out of it and start walking around like nothing happened. So I tell ‘em, “Man, you’re going to die doing this new stuff. Man you look dead.” Unfortunately, he did die.
Short High	Female, 36: Fentanyl hits you right away but it doesn’t last. I think when they put the fentanyl in the heroin, it cut the half-life. Because nothing lasts…nothing. If you got something that lasts for more than ten minutes [after the initial rush], you found some really amazing shit.
Short high causing more injections	Male, 23: But I’ll tell ya one thing, the thing that blows my mind, I used to not like fentanyl because it wears off faster than heroin. It’s so short lived and doesn’t last as long, so people use more, a lot more—every fucking 30 minutes to an hour.
Ability to Function	Male, 36: I’m not saying heroin doesn’t make you nod; if you sit down and relax, you know, you’ll probably get a nod going. But as long as you’re moving, you’re up and talking, it’s not as bad. I guess it [the heroin] is easier to function on.
Scary rush	Male, 36: Well, you know, when you inject it [fentanyl], you get this feeling and it hits you so hard that, you know, you immediately start thinking, “Oh shit, what have I done? What have I done?” You start getting kind of scared. You go look in the mirror and you’re like, you know, red and sweating and, shit, you’re like, Oh my God.”
Acute Respiratory Distress	Male, 34: The fentanyl is almost like a scary feeling. I mean, I went to this guy at 10:30 in the morning, got a little something from him, and then at 3:00 in the afternoon went back to him and got something completely different. And then I would do it, and as soon as I would do it, it was almost like an instant: ‘Oh, shit, this might be too much.’ It’s almost like a [gasping sound performed], like you can’t breathe. I mean you feel beads of sweating coming, building up on you, like you get kind of panicky, things get kind of dark.