Worried about a friend. HELP

A friend of mine has recently come off ALL drugs. He was a heavy weed smoker for years and also dabbled in other drugs such as coke and mdma over the last 10 years, but smoked weed on a daily basis for a very long time. Over the last several weeks his mental state has deteriorated entirely. He has recently also come of a long term relationship.
You would think that he would have a better mental state after quitting all drugs but it is like he is on even more drugs than before. He thinks that things are happening around him in the world that are entirely directed at him, weather changes, people he meets, other events etc. I have lived with him for the last 4 months. In his current job he is in the middle of creating a conspiracy involving management in regards to mafia activity and organised crime which just doesn't make sense. He thinks that our apartment is bugged and often asks me to meet him outside to discuss what he's thinking. He feels that he is being called upon to in a sense topple the house of cards in regards to corruption etc in the business. He everyday mentions how he has never thought so clearly in his life etc but that is not the case at all. He also says that he is not sure whether he is dead or alive. He thinks he may have died and is currently in the afterlife. He rambles and talks for Hours about the same subjects daily. He wrote "THIS IS NOT LIFE" on a bar coaster in our house the other day. I don't know what to do and I am very worried about his safety and my own. Can anyone tell me why he would be acting in such a strange manner after quitting drugs and also give me advice on what you think he should do to help himself. Please someone help me I am very worried and even afraid of what he might do to himself or others but mainly himself. What do I do??

Hello Btown: I see this is your first post here on PC. So welcome to PsychCentral. I'm afraid I can't really tell you a whole lot about this. I have no personal experience with the use of the types of drugs you describe. The only thing I can say is that, from reading posts here on PC, I have the impression the type of drug use you describe can really mess up a person's mental processes. Drugs don't simply disappear from a person's system, once he stops taking them, leaving it the way it was before he started. They have a lasting impact on the functioning of the person's brain.

Over time, your friend's brain became adapted to functioning with these drugs in his system. Now that he is no longer using them, his brain is having to go on functioning without them & it's not functioning well. My impression is this is not unexpected. From my non-professional perspective, you may well be right to be concerned for your friend's safety as well as your own. And, unfortunately, there's likely little or nothing you can do about this beyond encouraging your friend to seek the professional medical / mental health care he needs. Beyond that, I would suggest the most important thing for you to do here is to take whatever steps are necessary to protect yourself.
I wish you well...