i usually get mucus-y sinuses when i take acid, with kind of a cold metal feeling too,
as if my nasal cavity is made of spoons or forks...
nearly every time i trip, i have to go to the bathroom at SOME point in the trip and "de-mucus" my nose & throat.
after that im fine for the rest of it.
remember, drugs affect people differently.
although i HIGHLY, highly doubt that your man has the actual flu.
he just sounds like a pussy to me. a pussy who goes outside and spends his trips in the cold cold air or nekked, with no food, and stays up for ages,
thus depleting his health.