That's great to hear and I'm glad you understand everyone's concern and are not just shutting it out. But I do have some compassion that you might be getting frustrated that most of the replies have been about why not to use heroin as opposed to how you can reduce the likelihood of physical harm from using it and whether or not the effects you are experiencing are cause for concern. Not that you sound frustrated, your responses have been great

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I think it's great that you got a sensitive scale and are going to increase your dose by very gradual increments. Aside from what's already been said though I don't think there is much else I can say. Please take people's warnings about heroin not being worth it and there being no real way to prevent addiction aside from not using it seriously, and I'm not sure what else you could do to reduce harm if you're going to use it anyway, aside from always having someone else with you in case you do have any serious problems. Having had someone else around to call 911 has saved my life. I
suppose you could get a reagent testing kit, but those can be pretty difficult to interpret for heroin and don't give you much info about cuts, plus you're not planning on doing it for long, right?
Most dealers don't give a shit, unless they are the high-end ones who don't use drugs themselves and are businessmen first and foremost who really want your repeat business as they are thinking of future profits and not just immediate gains. Also dealers don't know what
their dealer cut it with. There was dope where I live that was making people who smoked it permanently brain-damaged and it took a very very long time to get it mostly off the streets (and I highly doubt that was due to any dealers stopping selling it out of concern for their customers). There was also dope that was contaminated with some bacteria that caused flesh-eating disease. Dealers often may not even
know if they have bad dope unless they have regular customers and everyone who uses it are dropping like flies.
Also your statement is ironic because heroin itself kills people. Most (not all of course, I'm not one of those people who thinks all dope dealers are evil or something) dealers care primarily about money, not people, and the ones that are only concerned with getting some fast money don't even care about keeping their customers alive in order to buy more drugs from them.
True, I'm not saying using heroin isn't dangerous. What I'm saying is that it shouldn't be any more dangerous than folks taking hydromorphone or some like potent opioid. Well, actually it
should be even less dangerous than that (as many docs don't give their patients info on dilly's and how they interact with other CNS depressants).
Anyways, I think you understand what I'm say, given it's one of the core ideas of Harm Reduction - that the situation we're created for ourselves that drug users are forced to live within makes things much more dangerous than they'd be in a better situation (i.e. where people didn't demonize junkies). Wishful thinking, maybe, but whatever. I think being fatalistic is kinda romantic sometimes
I'm going to put together a list of case studies for this, examining how the circumstances under which users find themselves kills them much faster than any of the drugs they use. That's the value of working with harm reduction groups and needle exchanges on the ground level, getting to actually work with such populations. I am trying to follow in the footsteps of E.V. Debs
while there is a lower class, I am in it, and while there is a criminal element I am of it, and while there is a soul in prison, I am not free
That's mah motto baby
And in terms of experimenting with heroin, yup, it's possible. My SO used heroin one time, as she was interested into the experience as I'm such a fan. She ended up using 30mg of pharmaceutical grade/99.99% pure/lab grade diacetylmorphine over the course of 48 hours. Intranasal (allergy dose) and IV. Never touched it again (and this is ten years later sorta deal). And it's not like she didn't get MAN high. And it's not like she doesn't love opioids, she just didn't want to deal with all the bullshit surrounding heroin use. Kinda like how I am not. Just too much of a PITA after playing the game for so many years...
I know others who've used once, twice, maybe three times, and stopped to never use again. Others have used for a number of months (my bro, three months of intranasal use) or years (me, five years, 2 intranasal three IV/mostly IM) and then stopped with little/no desire to use any more.
Heroin can ruin lives, but it's not the heroin that is actually ruining your life. It's you. This is where the disease model breaks down for a lot of people, although I'm not saying it doesn't have a LOT to offer or isn't the best model we have figure out as of yet.
If you wanna use heroin, do it. But think twice. Maybe even like four times

It's probably not going to destroy your life any quicker than any other potent opioid, although if you get caught up in the legal/social aspects of it it might, but again that's not the heroin it's the laws.
Don't get me wrong, it's not in no way fucking whatsoever safe. But, and what? A lot a LOT of things we do every day isn't safe. Heroin is like speeding. It's dangerous and could very well get out of control and kill you. But you're more than likely to get away with it more often than not. No guarantees of course, but you get the idea.
Using heroin is playing with fire, whether you use it once or for the rest of your life. Of course the more you use it the more dangers it poses. But shit guys and gays, heroin is hardly the only dangerous thing we do.
For whatever it's worth, the vast majority of heroin users I have known well have stopped using on their own or with the help of methadone or buprenorphine or naloxone. It's not rocket science. For many if not most of us, the ordeal of getting and having to deal with dealers, etc, using, getting sick, having to schedule life around our habit, it just takes its fucking toll. After a while it's just not fun or pleasurable in any way any more. At that point, me and such folks just stoppped. It wasn't worth it anymore.
And for the record, when I was talking about dealers I was referring to what I guess most would refer to as the big fish. Not junkies selling to cover their habit, but big distributers. Absolutely agree, most junky/using type "dealers" selling to cover their habit really don't give a fuck (although, again, I'd imagine most of them realize they need their clientele alive...), but when it comes to folks who deal in bulk or wholesale, I've yet to meet or here or one who wasn't to do like the DEA, LE and the US Gov't. Unlike the latter, big dealers don't want their clientele dead, they want them happy and healthy, productive so they have the money to buy their product. Got ten plus years experience dealing with these fuckers and they're infinitely more humanistic than any cop (or to be truthful low level dealer who doesn't give a fuck) I've ever heard of.
Oh and for the record, unless I get my hands on some pure diacetylmorphine to add to my collection (yes I collect rare and antique opioids - my best so far is the morphone kits they gave to marines in WWII and a hypo cicra 1865, and I just used my hypo from 1911 to IM some hydromorphone :D
Even after using heroin for a decade, daily IV/IM for three years, at present, and for the last year plus since I got clean, I have had absolutely no desire in the world to use heroin. Even with it around all the time, as I work at a needle exchange, even when I was working for a distributor, even when I'm sick (or was sick), even when it is offered to me for free (happens once in a while) and the dope happens to be fire, no fucking thank you. Although I guess I should add I'm rarely if ever sick these days. only time I can remember was when I was coming off buprenorphine. Anywho, so even if you do get into the dope scene and end up dependent/addicted, there is still hope. Have fun while you can, and pray that like the majority of users you'll eventually get sick enough of the conditions under which you have to use to the point where using is in no way desirably anymore, even if you need it to get well, eventually you'll probably just get sick of it and stop using. That's by no means a free pass,
when you use heroin you're still playing with fire, but at the same time it's hardly the end of the world.