Get emergency help, if needed
If you believe someone is at risk of suicide (or has made a suicide attempt):
* Don't leave the person alone.
* Call 911 or your local emergency services provider right away. Or, if you think you can do so safely, take the person to the nearest hospital emergency room yourself.
* Try to find out if he or she is under the influence of alcohol or drugs or may have taken an overdose.
* Tell a family member or friend right away what's going on.
If a friend or family member talks or behaves in a way that makes you believe that he or she might commit suicide, don't try to handle the situation without help. The most important step you can take is to get help from a trained professional as quickly as possible. The person may need to be hospitalized until the suicidal crisis has passed.
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Take all signs of suicidal behavior seriously
If someone you know says he or she is thinking of suicide or is behaving in a way that makes you think the person may be suicidal, don't play it down or ignore the situation. Certainly, not everyone who has thoughts of suicide or talks about suicide actually attempts it. But many people who commit suicide have expressed the intention at some point. You may worry that you're overreacting, but the safety of your friend or loved one is most important. Don't worry about straining your relationship when someone's life is at stake.
You're not responsible for preventing someone from taking his or her own life — but your intervention may help him or her see that other options are available to stay safe and get treatment.
http://www.mayoclinic.com/health/suicide/MH00058