Finding footage of people shooting dope is shouldn't be too hard, but not at retail outlets or in Hollywood. For more footage than you will ever need, Check out any college film programs stock footage and archives of student films, especially from around 1995-1998...
The world was a different place back then. Kurt Cobain had made heroin cool to every teenager in America and then killed himself so they would get depressed enough to actually go out and try it. "Heroin Chic" was all the rage, though heroin itself technically wasn't. A little film called "Trainspotting" was showing the world the irresistable appeal of stupid Euro trash accents, and banging heroin. And Rich suburban white kids overdosing became the biggest craze since breakdancing...
[Editor's Note: Shout out to all my niggaz in Plano who never made it, muthafuckas be readin this shit from heaven right now fo sho'. We wuz crazy off tha hook back then for realz, shit was tight. Special props to my nigga Snoopy for bein on muthafuckin' MTV when they wuz down here doin their "special report" shit on all us niggaz dyin' all the time. Plano be representin in heaven and shit fo sho' now, us niggaz down here still be pourin 40's for yall dead muthfuckaz, rest in peace on da realz yo.]
Anyways, sure enough, every freshman film class in America was filled with jaded post grunge high school grads away from home for the first time, so everyone channeled all thier angst and apathy into thier "art", and there was almost always an obligatory junkie scene, even though most of them had never even seen heroin in real life before...
In regards to filming a detalied "how to guide" for IV injection...
This isn't really practical for a number of reasons...
The basics of IV admin CAN be essentially be related to someone through a FAQ or film, definitons (unit, CC, gauge), the simple mechanics of the whole procedure (i.e. equipment needed, how to use a syringe etc etc), and of course these motions are in every typical shooting scene, they are not a problem...
The critical parts to correct IV administration are ones that cannot be reasonably translated or taught through FAQ's or educational films alone they are eventually and almost universally learned via personal hands-on experience and practice...
99% of the difficulties people have with learning proper IV admin revolve around two basic things:
1. Doseage issues
2. Detailed specifics in reagrds to the vein.
Both of these couldn't be taught for obvious reasons, they are much to relative to the individual situation and thus accurate broad educational statements regarding their specifics could not be given.
Learning how to "find" a vein if it's not readily apparent (this is an art in itself), at what angle to hit it, how to prevent piercing through it or missing it altogether, how to draw and confirm a solid hit, and the technique for mainting all the above specifics while pushing the plunger in so as not to miss...
You can't really learn that from a book or film. It's like learning to ride a bike or swim, it's real simple shit, but you can't really do anything but tell people the basics, and they kind of have to feel thier way into it with trial and error and eventually truly learn it...
So essentially, you can outline the basics like so many films have done, but you can't do much for relating the critical IV injection dynamics adequatley on film, couldn't hurt to try though...
Brainrape
PS- For the record I have never included a traditional junkie shooting scene in any of the short films I did, cause you know, I am way to cool for that. I didn't really know anyone in Plano into the smack scene back then except a few casual acquaintences, and one kid I met at a party once who was actually one of the fatal overdoses, oh, and Snoopy. My friend Snoopy really was on MTV when they did thier Plano/Heroin special, he is shown for like 30 seconds sitting and fixing a rig against some graffiti ridden wall, but of course MTV made him do all that. In reality most of the kids who fatally OD'd back then died from SNORTING heroin, needles where generally looked down upon, which I suppose is good, if they had been IV'ing, the death toll would have been much much higher. Oh, and Breakdancing will never die.
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"Rock and roll adolescents storm into the streets of all nations. They rush into the Louvre and throw acid in the Mona Lisa's face. They open zoo's, insane asslyums, prisons, burst water mains with air hammers, Chop the floor out of passanger plane lavatories, shoot out lighthouses, turn sewers into the water supply, administer injections with bicycle pumps. They shit on the floor of the United Nations and wipe thier ass with the treaties, pacts, alliances."