"Emotion Sickness" is the fifty-third episode of Kim Possible and the second episode of the third season.
In an attempt to foil yet another scheme of Drakken to steal from Cyrus Bortel, experimental mood altering devices accidentally get attached to Kim and Shego. During the chaos, Ron accidentally picks up the control for the devices instead of the Kimmunicator, activating them. As a result, confusion for both Ron and Drakken ensues as the former mistakes the device for a video game as it sends the girls hurling through a range of emotions, including anger, sorrow, and even love, which means major mayhem for Ron and Drakken.
- This is the first time Kim and Ron have actually kissed, unless one counts Kim kissing Ron on the cheek under the makeshift mistletoe (actually a piece of parsley with a red ribbon tied around it) in "A Very Possible Christmas".
- According to Steve Loter, the producer of the series, the episode was a test to see how the fans would react to the possibility of Kim and Ron having a boyfriend/girlfriend relationship.
- The episode was voted #1 in the Disney Channel's "Kim Possible Click it to Pick It: So the Countdown".
- In the previous episode, "Steal Wheels", after Drakken and Motor Ed stole Felix Renton's wheelchair, Shego asked "What's next. Candy from a baby?" In this episode, she did just that.
- When Ron is talking to Kim at the Middleton Days Festival and accidentally presses a button on the moodulator, the device is in his left pocket, however when he takes it out to show Cyrus Bortel he takes it from his right pocket.
- Twice, the moodulator control shows a purple gloomy face instead of the blue crying face: When Dr. Bortel is testing the moodulators at the beginning, and when Jim and Tim are fighting.
- When Dr. Possible takes the Moodulator control from the twins and sets it on the table (inadvertently turning it to "Romantic"), the face on the screen is the purple "Romantic" face before the button sound effect.
- During the musical interlude when Ron is fleeing Kim and Shego and Drakken are in the park, Ron crouches at a corner with lockers on either side of the wall. When Kim surprises him from behind and the view switches, the left wall is still lockers, but the lockers around the corner have vanished and been replaced by a door.
- Though this was the second time that Dr. Cyrus Bortel had met Kim and Ron, he did not seem to recognize either one in this episode. His mistaking Ron for a spy was understandable as people commonly forgot Ron. But Bortel knew Kim on sight when they first met, yet he never referred to her by name in this episode. Although oddly enough, Ron did not seem to remember Bortel, either.
- One of the floats at the beginning of the episode features Ron's supposed ancestor from "Rewriting History".
- When Kim wins the pickle doll for Ron at the fair, the other competitors are wearing Rocket Booster sweatshirts from "Monkey Ninjas in Space".
- Another boy skating in the park during Drakken and Shego's outing also was wearing one.
- This is Dr. Cyrus Bortel's second appearance, having first appeared in "The Twin Factor". It is also the second time Team Possible had to deal with his mind-altering technology in Drakken's hands.
- Shego says "You talkin' to Me?" - one of the most famous Robert De Niro lines from Martin Scosese's, Taxi Driver.
- Kim says "You got some 'splaining t'do!" - a catchphrase from I Love Lucy.
- The mood swings of Kim and Shego are similar to the Emoticlones of Raven in Teen Titans.
- When Kim and Shego get angry and halves of their faces appear on a splitscreen, it is similar to how Bruce Banner turns into the Hulk.