My 24yr DS has twice this month gone out and get totally incapable of keeping himself safe through alcohol and possibly drugs, last time few weeks ago he was lucky and police returned him home and a very nice man found and returned his phone, fast forward last night went out with long term friends for few drinks and watch boxing all left together but my DS never got in same taxi when they went home around 11pm, at 1am I received message going clubbing around 4.30 I message to ask if on way home reply was not yet, after this no reply from him or answer this phone, contacted his friends who tell me above they all went home early, rang police friends out in cars looking for him only for him to be brought home at 6.30am by 2 strangers in a cab he is currently in bed asleep any advice on best way to approach this unacceptable dangerous behaviour, normally hard working, funny, caring young man