Let’s pretend that Kanye West is a long-term drug user. As a…

Let’s pretend that Kanye West is a long-term drug user. As a result of his chronic use, his behavior and functioning have completely changed. He is very paranoid, he experiences tactile hallucinations (e.g., he feels like bugs are crawling on his skin), and he engages in useless and purposeless behavior like constantly sorting and resorting his silverware drawer. What drug has Kanye probably been using?