Hi there ~
I understand your concerns. I believe that your friend is on many substances and has been taking these substances for a long period of time. I hope you can talk your friend into going into rehab. I believe you need to consult a psychiatrist
who can help with getting your friend help for all the medical problems and long term neuropsychiatric problems that is probably occurred due to polysubstance dependence. I hope you do so as soon as possible to get your friend a chance to be normal like before.
I hope this helps. Take care of yourself and have a lovely day!