It CAN happen suddenly like that. I just had an overdose come "out of the blue" with a comment my husband said. Please try to get him to the ER or some place that can help him. He doesn't realize his thoughts are all wrong if he is delussional. I've been there & seen it in my mother--you don't want to wait it out---it won't get better without help. My thoughts are with you. I'm concerned.--Suzy