This film tells the story of a heroin addict, and in many scenes we see him taking drugs, or prepare. The use of heroin is not absolutely graphics like Trainspotting or Christiane F., but it is still quite strong.
A character knows a girl who use heroin, so he starts. We see them prepare heroin, put it in a syringe and inject it. (This step is a bit 'strong)
In another scene, we see the same people inject heroin.
It's implied that he will continue to shoot up.
A character goes in overdose and is abandoned. Really sad.