How addictive is Heroine? I keep hearing that "*Heroine is so addictive the very first dose is enough to get you hooked on it*".

Personally, I have a hard time believing any substance could do that to you.
But I could believe people spreading that idea to discourage people from consuming it.

Now obviously, I have zero desire to test that hypothesis myself. :P

Still, I'm curious. Does anybody know papers that shed some light on this matter?
"The United Nations World Drug Report 2013 estimated that approximately 16.5 million people worldwide aged 15 or older used heroin or opium. Of these users, approximately 23% are estimated to develop opioid dependence."

This is from the introduction section of Hser, Y. I., Evans, E., Grella, C., Ling, W., &amp; Anglin, D. (2015). Long-term course of opioid addiction. Harvard review of psychiatry, 23(2), 76-89.

They cite:
United Nations Office on Drug and Crime. World drug report 2013. Vienna: UNODC, 2013.

&amp;

Anthony JC, Warner LA, Kessler RC. Comparative epidemiology of dependence on tobacco, alcohol, controlled substances, and inhalants: basic findings from the National Comorbidity Survey. Exp Clin Psychopharmacol 1994; 2: 244–68.

There are various factors that push that probability up or down, sex, age, personality factors, circumstantial factors, some people would have a higher probability, some lower. But the base-rate probability is roughly 1 in 4. For perspective, it's worse odds than Russian roulette (1 in 6), but better odds than unprotected sex leading to an unplanned pregnancy (somewhere around 1 in 3, depending on various things). If you're comfortable with the folk-wisdom of either "Russian roulette will kill you" or "sex leads to pregnancy" you should also be comfortable with the statement "heroin will get you hooked". Sure, they're all approximations, but not terribly misleading ones.