LORELAI: I’m still . . . uh, these allergies really just hit me like a ton of bricks.
EMILY: I’ve never heard you mention allergies before.
In a future season, Lorelai needs allergy medication, and has old packets stored at home, so it seems that she really does suffer from allergies (even if she’s making it up right now). Or they changed it so that Lorelai actually has allergies.
The Annotated Gilmore Girls 