Actually I dunno which is worse - heroin or cocaine. I'm inclined to go for the former. I've seen a lot in my life what heroin does.
Turn father against mother, son and daughter. Makes thieves of everyone who do it. Families gone to the streets because of this addictions. Turned men into shell. Big strong men into skinny scarecrows. Horrible addiction. Within 3 days you can get addicted for life.

And really for life. I've known people who've gone years even 10-15 years without smoking or injecting it, then 1 relapse - kaput, back as you were. From smoking to injecting. Yes, even when no available vein, they go for the penile veins.