Sickly Neurotic Geek

This character is frequently seen as a sidekick to the lead, and will be a Hollywood Nerdly type. He will likely speak as though his nose is constantly congested, have myriad absurd allergies (and it usually is allergies, unless he needs a Nerdy Inhaler for his asthma) and go to equally absurd lengths to avoid any further ailments. Expect him to talk about his long list of medical issues openly and graphically whether he's asked to or not. His health issues are often implied to be psychosomatic, or Hypochondria: If this character takes a level in badass, expect them to clear up pronto.

Whatever the actual level of ill health, it will be a sign of physical incompetence and social awkwardness - or at least, that's what everyone will assume.

Compare Jewish Complaining, Drama Queen.

Anime and Manga

 * Joe from Digimon Adventure, although it's mostly just played up in the dub.

Films

 * Nick Szalinski from Honey, I Shrunk the Kids
 * Who is almost a carbon copy of his father, Wayne.
 * Georgette in Amelie
 * Daniel Jackson from the original Stargate movie. His allergies act up while traveling. Daniel's allergies play as a plot point sometimes in the spinoff series.
 * Cameron from Ferris Buellers Day Off
 * There's one in National Lampoon's Van Wilder: Party Liaison; He just goes by the name of "Sick Boy" most of the time.
 * Matt Farrell in Live Free or Die Hard. He spends most of the movie complaining about his asthma and blood sugar levels to John McClane but later becomes a Badass Bookworm.
 * Woody Allen in practically everything he's been in.
 * Joel Glicker from Addams Family Values.
 * Among the four geeky leads in Fan Boys, Windows is this.

Literature

 * Joly from Les Misérables, who is a hypochondriac, fits this description, though due to the large cast of characters, isn't actually a sidekick. He aligns his bed to fit with the magnetic poles!
 * Eddie in Stephen King's IT, courtesy of his mother's apparent case of Munchausen by Proxy.

Live Action TV

 * Felix from The Odd Couple, especially the TV series which Flanderized his allergies.
 * All of the Dorfmans from iCarly, also Jeremy. Freddie's mom treats him as though he is; this has gotten more and more ridiculous as his actor has gotten bigger and her character has gotten Flanderized.
 * Lisa Zemo, who started off with braces, Nerd Glasses, and a perpetually stuffy nose. Subverted, however, because a season or two later she comes back looking less nerdy and on a new allergy medication.
 * Howard Wolowitz in The Big Bang Theory.

Theater

 * The eponymous character in The Nerd is like this.
 * William Barfee in The 25th Annual Putnam County Spelling Bee. Among other things, it's mentioned that a severe allergic reaction forced him out of the previous bee.
 * The eponymous character in the several versions old Yiddish play The Two Kuni-Lemls is like this—limps, thick glasses, easily confused. Has a long speech about his health problems, including "I get indigestion when I walk." (The first version was a satire of Hasidism. He's an "ancestor" of the Jerry Lewis character.)

Video Games

 * Bentley from Sly Cooper

Western Animation

 * Carl from The Adventures of Jimmy Neutron
 * Macie from As Told by Ginger
 * Melman from Madagascar
 * In Ruby Gloom Misery's cousin Malady (an occasional guest character) will always treat the phrase "How are you?" as a cue for an epic description of her ailments, usually finishing with something like "...it's a scrape. I'll be fine."
 * Kyle Brovlofski's cousin Kyle in South Park
 * Chuckie and his dad from Rugrats and All Grown Up!.
 * Tino's cousin in The Weekenders is a subversion: he was a this when they were younger, and Tino dreads hanging out with him because of it. Once he finally lets his cousin get a word in edgewise, though, it turns out that he's now both healthy and cool.
 * Mendel from Godzilla: The Series. He's got allergies to everything.
 * Milhouse from The Simpsons
 * Arnold from The Magic School Bus
 * YMMV: Arnold's claims of illness/allergies could be a desperate attempt to avoid being taken on the (frequently bizarre and sometimes very dangerous) field trips that Ms. Frizzle seems to be so fond of.
 * Filburt from Rocko's Modern Life who becomes physically ill even from the most mundane of tasks. "I'm nauseous. I'm nauseous. I'm nauseous. I'm nauseous..."
 * He also has Super OCD. "Turn the page, wash your hands. Turn the page, wash your hands. And then you turn the page. Wash your hands.."
 * Total Drama seems to assume that absolutely every geek is allergic to something—Harold fits this trope the best, but Noah also mentions "life-threatening allergies" that never really come up again, Ezekiel has a "sensitivity" to peanuts, and the Amazon episode of World Tour has a plot point where Cody needs to carry an EpiPen because he's allergic to basically everything in the rain forest.
 * Then again, it's shown that Gwen, Leshawna, and Courtney also have challenge-impacting allergies, and Noah is more than likely just using an excuse.
 * The nerd in TDA Aftermath who asked Leshawna a question.
 * Gordy Rinehart from Angela Anaconda.
 * Subverted by Gretchen from Recess. She has the nasal voice, but otherwise doesn't have any known illnesses.