Wait, shooting anything IS hygienic? Putting toxic chemicals in your body by ANY method is hygienic?? Sure, some are more so than others, but how's a midget gonna go and look down upon a dwarf? [all pun intended]
I'm just saying, for the record, if you really care about hygiene and health, don't go doing drugs in the first place, and if you actually have to for medical reasons, don't abuse them, and finally, don't start with that I-may-have-just-had-gay-sex-with-another-man-for-an-8-ball-of-coke-but-at-least-I'm-not-one-of-those-disgusting-crack-smokers mentality. That said, I apologize for being so judgmental, myself, and will get back to the topic.
As for shooting fentanyl, I really don't see it as all that dangerous if you've got a high tolerance and are using the gel-type patches. I use to do it on a regular basis, and never came close to overdosing from it[forget the mcg/hr, though]. At least with those, as opposed to the heroin I was also doing at the time, you could tell relatively precisely how much you were putting into your body, more accurately than smoking it, even. On the other hand, yes, you'd better know exactly what your tolerance is before your try it, or start with the smallest possible dose until you figure it out, because that stuff is POTENT. Around the same time they were cutting the heroin with it before selling it on the street, and I know quite a few people who went out on The Everlasting Nod because they didn't realize how strong the stuff is. So if you want to try shooting it, I'd suggest getting the gels, watering them down[say, 5-10 parts water] and then starting with an incredibly small shot, even if you're sure you won't feel it. For example, if you got a 100 mcg/hr patch, water it down with 10cc's and then try injecting a tenth of a cc at first. I think that'd be about 1/10 of a milligram dose, BUT I DO NOT KNOW FOR SURE SO CHECK AND RECHECK THE MATH BEFORE TAKING THIS DUMB-ASSES WORD! That was just an example, everyone's tolerance is different, but hopefully you get the idea and know your body better than I do, so take care, have fun, and BE SAFE! [and please, no one go and die because I encouraged this]