Clearly, this drug does something to the person's brain that is so profound that it overrides even the basic survival instinct. Like, it's eating away your body right before your very eyes, hello!
I saw a video on people addicted to smoking coca paste
in South America. All the addict does is seek out the stuff, prepare it and smoke it. Non-stop. No food, no water. It eats away the brain and the person ends up a babbling lunatic.
This stuff is so awful that young addicted people who are wealthy enough have submitted to experimental neurosurgery, where the pleasure centers of the brain are severed. They are willing to risk never feeling pleasure again in life, in order to quit the stuff and regain some control over their lives.
This krokodil appears to be even worse. Like volunteering to give yourself leprosy or to become a walking zombie. Yech.