How to tell if someone is addicted to drugs (Pain Killers, Cocaine, and Nerve Pills)?

Question by ♥ι’м тнє gιяℓ ωιтн тнє тαzєя: How to tell if someone is addicted to drugs (Pain Killers, Cocaine, and Nerve Pills)?
What are the “symptoms” of an addict? I’m not asking how to tell if someone is using them. It’s obvious that the person snorts them daily. But how do you tell if they’re addicted to them?

Also how would you know if you/someone else is addicted to cocaine. It’s possible to do drugs without getting addicted to them so how do you tell if you/someone is doing them for fun or is in denial and really are addicted? It’s hard to explain. In other words how do you tell if you’re addicted to drugs and not just doing them for fun?
oops. wrong cat.

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