hallucinate

həˈluːsɪneɪt

verb

experience a seemingly real perception of something not actually present, typically as a result of a mental disorder or of taking drugs.

Ben began hallucinating and having fits

have hallucinations,imagine things,see things,see visions,be delirious,have delirium tremens,fantasize,daydream,dream,have a trip,trip,see pink elephants,have daymares