How can you help your 22 year old son who is a drug addict and homeless?

to be honest... you may not like to hear this answer but there is nothing that YOU can do. it seems the more you try to help the more you get pushed away. trust me i know I'm 21 years old now and was also homeless and addicted to heroin, along with other substances; but until he wants to get help for himself and actually wants to be clean and sober, there really is nothing you can do. He has got to want it for himself. Sorry if my answer is not what you wanted to hear but its reality...