Bupe Buprenorphine not burning arteries?

[Animoe]

So I've been injecting Bupe for years now, but when I hit an artery it doesn't burn like it did with Heroin, if at all. I've recently started adding Diphenhydramine to my shots so that I can feel if I'm in an artery and pull out right away. Does anybody know why this is though? I have hit a good handful of arteries in the years I've been injecting Bupe, but no complications from any of them. I do filter the fuck out of my shots though. They go through 2 coffee filters, and 2 cottons. I'm wondering if it doesn't burn because they are filtered to the point that they just look like slightly colored water.
I don't know though.

Edit*

I'm also wondering if it's because Bupe is less caustic than Heroin?

 

[Tek4242]

Every single time I've hit an artery and actually shot any amount into of bupe into it, i knew by the time only a few units had left the syringe. Anything below, or away from my heart for lack of a better term, was on fire and almost immediately swelling. Although i do agree it's not quite as bad with bupe as say dope or coke, it was certainly very unpleasant and definitely noticeable. Could it be that you're not actually hitting an artery, but just think you are? Nothing that i know of, even straight water won't result in pain, swelling, or some type of negative and probably dangerous reaction.

 

[clubcard]

Going into an artery only takes 1 bad hit for you to lose a limb. In the UK its abuse was first seen on the Scottish islands where every drug is rare. While it is a sublingual tablet, it isn't designed to be banged up. Adding 1st generation antihistamines is considered especially risky. I grew up in the throws of Diconal and Palfium abuse. I've seen the outcomes. You know your own body more than anyone else but do bear in mind that the mixture of opioid & antihistamine has a long and uniformly bad history. If you can wash it all down, smoking is safer than digging and for the mixture you mention, almost identical.