My friend is experiencing paranoia and believes he is being monitored by the cartel or the government. He is a functioning human that can hold down a job and I am the only person who he has told about his belief. He is constantly changing his phone number and moving to different states, so everyone knows something is going on, but no one knows exactly what. Turns out it is because he believes he is being watched. How do I approach this subject with him? He trusted me enough to tell me and I want to help him.