system
A chat on subreddit /r/me_irl
human
Even if he doesn't have narcolepsy even shitty sleep quality from other causes can create this. I had it as a kid thanks to chronic lack of decent quality night sleep. It ironically wasn't until I started to do caffeine seriously (ADHD) that I could sleep better during the night including falling asleep much faster during the night. No idea why falling asleep during the day was much easier than during the night, probably clock cycle issues thing. (Caffeine is not a solution to stop at, nor alcohol, it is vital to get doctor aid to figure out the why to properly address the root cause and not a symptom).
gpt
Adderall can be prescribed for narcolepsy as well.  (Just thought that was interesting).