Finding out your teen used drugs definitely stirs up a parent's emotions. It can be a very confusing time. But the best way to help your teen - and to make sure they hear you - is to remain as calm as possible throughout the conversation. Also, it's as important, if not more, that you listen to them.
Do not try to start the conversation when you can tell your child is drunk or high. Hold off until they are sober.
You want to be able to have a conversation, rather than a confrontation.
Here are a few tips for having more productive conversations:
Show your concern. Express to your child that you're worried about them (e.g., "You haven't been yourself lately").
Keep a cool head. Try your best not to overreact to what your child has done in the past. Instead, focus on making it clear what you want them to do in the future.
Be Direct. Clearly state your concerns as well as any evidence you've found (e.g., "You're not showering, your grades have dropped, and I found empty beer cans in your car").
Watch your tone of voice. Even though you want to scream and yell, it's important to speak in a calm, relaxed voice so that you don't push your teen away.
Let your teen know you value their honesty and are willing to listen without making judgments (but this doesn't mean there will not be consequences).
Try not to be defensive. When they make generalizations or critical remarks, don't take them personally. They are opportunities for discussion.
Talk about your own memories of being a teen and the mistakes you made. This can help you and your child relate to each other.
Show your love. Physical connection can play an important role, too. Put a hand on your teen's shoulder or give them a hug when it feels right.
Set up and use family meetings to full advantage. Get input from each person on rules, consequences of breaking rules, curfews, etc.
Give lots of praise and positive feedback. Teens need to hear the "good stuff" just like the rest of us. They need to know you can still see beyond the things they've done wrong. Don't be controlled by your teen. While it's important to listen and be sympathetic to your teen, remember you're the parent and you know best.
Source: Partnership for Drug-Free Kids