Maybe, but if he's a crack head it's more likely that he's cooking up his own crack. I'm not exactly sure how this works but you can mix coke with something else, apply heat, and it turns it into rock. Maybe someone else can elaborate?
It is a good indicator that he is injecting drugs. Either he is cooking his own crack or he is now using heroin along with crack which is a very popular trend.
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It can mean he is either cooking a drug but it does not mean he is shooting it. Or he is shooting a drug after cooking it. Why don't you ask him what his use is and tell him you are concerned? That is enough for several recreational users not to continue using. if he still uses - then he is probably addicted and talking to you might help him but won't cure him. He needs help kicking. If it is heroin research Ibogaine treatment. If it is crack - put him on an anti-anxiety or get to the real bottom of his issue. Most people addicted to crack are bored or have another major issue. (From the crack addicts I have personally known - they are usually less dependent chemically than heroin users I knew.) Either way talk to him and don't make it a moral issue. Talking down to him or being a prick won't help anyone. Be supportive. Most likely he is lonely or has another major emotional issue and any derogatory behavior on your part will make him worse.
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