We discover in this episode that the hearing of a human is slightly more acute than that of a Cardassian.
Dr. Bashir celebrated his 30th birthday in this episode.
Nitpick: Usually, Bashir has any number of Bajoran nurses and assistants on duty, especially if he is out of his office. So how did Altovar gain such easy access to the Medical lab, while Bashir was on lunch? There would be someone on duty there in the event of emergency, and Bashir would not have been alone there in being attacked.
Goof: When Bashir and Garak enter ops, you can briefly see the point where Andrew Robinsons' make-up stops.
Nitpick: When Bashir gets to Ops his hip is supposed to be broken. Well, for someone who has just broken his hip, he is still walking pretty fast.
Pseudo-Jadzia: But if you're in a coma, and we're not real, then what are we doing here?
Pseudo-Odo: Well, maybe we're just here to give him someone to talk to.
Pseudo-Kira: (laughingly pointing to Odo, O'Brien, and Dax) A paranoid, a coward, a hothead, and me? Oh, you'd think he'd pick some better company!
Garak: I wasn't aware that humans saw growing old as a negative experience. On Cardassia, advanced age is seen as a sign of power and dignity.
Garak: You'll have to excuse my friend here. He's turning 30.
Bashir: And If I had to guess Chief, I'd say you represent my self-doubt.
O'Brien: No, I don't!
Garak: After all this time, after all our lunches, you still don't trust me... there's hope for you yet, Doctor.
The episode won an Emmy Award for Outstanding Makeup for a Series.
Cirroc Lofton (Jake Sisko) does not appear in this episode.
The name "Lethean" is derived from Greek mythology. Lethe was one of the several rivers of Hades: those who drank from it experienced complete forgetfulness.