Being sick is no fun for anyone. There's the fever, the aches and pains, the need to sleep, the runny nose, and a plethora of other unpleasant symptoms to contend with.
For magical or powered characters in fiction, particularly in animation, the above can come along with a Malfunction Malady. Regular symptoms of the common cold or other condition may be compounded by Power Incontinence, or a form of it. Powered characters who come down sick may find their powers firing off uncontrollably with every sneeze.
Worse, when they attempt to use their powers intentionally, the result is a Magic Misfire - the effect they wanted affects the wrong target, inflicts a bizarre effect on some innocent bystander, fizzles, doesn't happen at all, or comes out completely random. Naturally, Hilarity Ensues.
Worse yet, sometimes the effects are caused by something perfectly natural, like puberty or pregnancy.
If this wasn't all bad enough, there is almost never an easy cure. Usually the hapless victim of the malady wonking their powers has to wait it out, or their friends and teammates have to go on a Fetch Quest for some strange, arcane, rare or mysterious item (perhaps a Flower from the Mountaintop) to get them over this disease and its dangerous side effects.
Use of this trope also tends to generate an Annoying Patient for any friend or family member nearby who isn't also sick or compromised by the sickness.
- Esper Mami had the eponymous teenager's telekinetic powers disassemble items when she sneezed—thankfully she was lifting a truck, not a person, when she discovered this. Her teleportation also gets wonky when she's drunk.
- When the eponymous telepath from Kotoura-san came down with a cold, it turned out that her ability to read peoples' minds was also blocked as a result. Notably, her boyfriend Manabe found out that he was able to fantasise about her as much as he liked without her knowing for once, but quickly came to realise that it was no fun for him unless she could see and react to these thoughts. Once Kotoura recovered from her illness, her telepathy followed suit.
- Negi from Mahou Sensei Negima! creates gusts of wind when he sneezes. Said Wind seeks out and strikes girls' clothing like a heat-seeking missile.
- A variation found in Slayers: female mages suffer a severe loss in power when it's "that time of the month".
- The Frozen fanfic "Childish" has a chapter where Elsa gets a cold and every time she sneezes she coats everything within several feet in snow. Later in the fanfic she and Anna have a pillow fight and this happens again when a feather tickles her nose.
- The Homestuck fanfic "SWIMMING WITH SHARKS" points out the potential for such with Terezi's abilities. She normally perceives the world synaesthetically, via smell and taste... But in the fanfic, she gets a cold, effectively making her blind and entirely debilitated.
- The fan-video Weird Crossover between The Incredibles, Zootopia, Doc McStuffins and Tangled, The Incredibles Get Sick, has the Incredibles all coughing, sneezing, and (with the exception of Violet) sleeping a lot but with no fevers, and it affects all of their powers: Mr Incredible and Dash have lost theirs, Elastigirl's are out-of-control, Violet can't make force-fields and she can go invisible but can't turn visible again, and Jack-Jack is stuck as a demon. Some unknown electricity-like substance cures them.
- This can happen to Bloodliners in Pokémon Reset Bloodlines. For example, Jeanette sometimes accidentally uses Sweet Scent when she sneezes. And since Bloodliners are heavily persecuted, this can be very dangerous.
- In the My Little Pony Friendship Is Magic fanfiction Pound and Pumpkin Cake's Adventures (and Misadventures) in Potty Training, Starlight Glimmer gets the "horn flu", a unicorn disease that makes the unicorn's magic unstable and accidentally turns the twins into deer.
- In Animorphs, Rachel suffered this after scanning an animal she was apparently "allergic" to. This caused her to randomly assume her various animal forms and only ended with her expelling the new shape by vomiting up an entire alligator.
- Discworld: In The Last Continent, The Librarian at Unseen University catches a cold and turns into something new every time he sneezes, thanks to his "morphic field" being weakened by his original transformation from a human into an orangutan.
- The entire plot of The Exploits of Ebenezum (and further sequels The Wanderings of Wuntvor) by Craig Shaw Gardner revolves around this. Ebenezum, a talented hedge wizard, accidentally summons a demon and is somehow cursed by the Netherhells while sending him back. This causes him to develop an "allergy" to magic, interrupting every one of his spells with a thunderous sneeze. At first this is thought to be the work of said demon, but later even he proves unable to reverse it. So his bumbling apprentice Wuntvor has to help him get from one place to another looking for a cure. In case it wasn't obvious, this is a quite funny modern fantasy parody.
- It's commonly believed in the Heralds of Valdemar universe that female mages can't cast spells while pregnant. The brother of a very powerful sorceress pointed out that he knew several people who put this to the test and didn't live to admit that they were wrong.
- In The Wheel of Time Elayne Trakand becomes pregnant, and the Aiel Wise Ones inform her that she will occasionally be unable to channel.
- In the Wild Cards novels, Peregrine is shocked to discover that she loses her ability to fly while she is pregnant.
- Young Wizards: In So You Want To Be A Wizard?, Nita and Kit unintentionally transport Fred the sentient white hole to them. White holes emit stuff - usually energy. Most of his mass and energy is stored in a temporal-spatial pocket so that he can travel at all, and the act of traveling has made him a bit woozy - it gives him a bad case of the hiccups. When he hiccups, he emits stuff. And by stuff... good luck trying to explain the Learjet that just appeared in the middle of the field.
- The 4400: The immune system deficiency created by the promicin inhibitor causes the abilities of the affected 4400s to stop working. In "Lockdown", Shawn is unable to heal a blind woman named Olivia Cohen. In "The Fifth Page", Maia tells him that she can't use her ability to see the future to find a solution. In the same episode, Alana is unable to distinguish between the real world and the world that she created for herself and Tom in "Life Interrupted".
- Bewitched: The same thing happened with the witches and warlocks in Samantha Stevens' family. It happened to Samantha, Serena, and Aunt Clara on separate occasions. There was also an episode where Sam's snarky mother Endora lost her powers because she was allergic to dodos and Tabitha conjured one up.
- Witch pregnancy seems to result in a lot of unusual and uncontrolled magic effects, though this is explained more as the magical fetus messing with things than the mom's magic going haywire as a result of pregnancy.
- In "Centennial Charmed", Paige gets a cold and accidentally teleports whenever she sneezes.
- Doctor Who: The TARDIS is prone to this, from giving its passengers a battery of incomprehensible warnings in "The Edge of Destruction" to suffering from Huon particle-induced indigestion in "The Runaway Bride".
- I Dream of Jeannie: Jeannie coming down with a cold would cause "blink" effects and random things showing up that Tony had to get rid of.
- Pee-wee's Playhouse: When Jambi the Genie comes down with "Meka-Leka-Hi-Meka-Hiney-Itis" (read: genie burnout), his powers don't work at all, and the magic rings that emanate from his turban come out slightly wibbly.
- Rentaghost: Nadia Popov would teleport whenever she sneezed. As she suffered from allergies, this tended to happen quite a lot.
- Sabrina the Teenage Witch used it at least twice. One was when Sabrina caught spellfluenza, which is a 24-hour sickness that causes one's powers to be transferred to the nearest person when one sneezes. Assuming they are the nearest person again during the next sneeze, the powers come back. Surprisingly, the person who got her powers was Ms. Quick. The other was when Hilda caught punitis, a disease in which everything she said resulted in a bad Visual Pun occurring (for example, when she asked for some ice cream, a screaming disembodied eye appeared in the freezer).
- The Secret World of Alex Mack: Alex got bubble hiccups, sneezed herself into a puddle, and lost control of her electricity. Exposure to several chemicals in other episodes reacted with the GC-161 and made her sick in ways like: parts of her body randomly morphing into water, out of control aggression, and static electricity.
- Smallville: In "Sneeze", Clark Kent discovers his Super Breath when he catches a cold, sneezes, and blows the barn door off its hinges and across the entire county, almost decapitating Lois. Much of the episode is spent trying to come up with believable reasons why the Kent barn door appeared in the middle of nowhere and it ends up inspiring Lois to become a reporter.
- Star Trek, "Plato's Stepchildren": One of the Platonians (or whatever they were called) was sick, and since they had telekinetic powers, that made furniture fly around as if there was a hurricane. Dr. McCoy cured him, and they showed their gratitude by forcing the Starfleet officers to star in a sadistic puppet show.
- That's So Raven:
- When Raven becomes ill with the flu, she reads people's minds.
- She also has a mushroom allergy. In one episode, this just caused her to comically swell up at an inopportune time. In another, it gave her random, incomprehensible visions, such as her father and brother dressed up as sailors and digging for gold on the moon.
- The Worst Witch: For a few episodes, Beatrice was teleporting (and occasionally teleporting other people) whenever she sneezed and she was sneezing because she was allergic to cats. Eventually, this was cured.
- In Aberrant, the Yin/Yang enhancement enables a nova with Mega-Appearance to switch between male and female forms. If the nova gets pregnant (a rare event), this enhancement will shut down at a certain point in the pregnancy, locking the nova in female form.
- In Monster High, Frankie is shown to inadvertently release electricity when she sneezes. And Abbey releases a burst of frosty air that can freeze things with her sneezes. But topping them both is Operetta, whose voice can reach supersonic levels, meaning supersonic sneezes. One sneeze from her shatters several windows and sends a few unlucky students flying out the door.
- "Hello, Ryu !" "Heddo, Ken!"
- Genie in Aladdin: The Series also caught a cold that caused random objects to appear every time he sneezed, with the objects becoming more dangerous as the disease progressed.
- American Dragon: Jake Long had an episode like this.
- Katara the waterbender gets sick like any ordinary person, but airbender Aang's sneezes launch him ten feet into the air; though that may be Aang being playful.
- This happened in a first season episode of Ben 10. Wildmutt was effectively blindnote , Fourarms was more disgusting and clumsier, and Heatblast became An Ice Person.
- In one episode of Adventures in Care-a-Lot, Funshine got a case of Bubbles, which made him cough up bubbles every time he hiccuped and start floating away.
- In an episode of Fairly Oddparents, Cosmo's Phygigly Gland (which controls a fairy's transforming powers) starts acting up, necessitating a transplant from Cosmo's Evil Twin Anti-Cosmo.
- A much earlier episode had Cosmo catching the "Fairy Flu", which caused him to randomly lose control over his powers every time he sneezed (one sneeze summoned a merry go round, another transported the house to the moon, etc.). For some reason, feeding him lots of sauerkraut cured him.
- It's either an inversion of this trope or Cursed With Awesome, but every time Glitter the sidekick fairy sneezed in Kidd Video, she temporarily gained super strength.
- Mega Man: Fully Charged
- In Flower Power, Mega Man develops an allergy and involuntarily switches forms while sneezing. It also causes him to speak in rhyme.
- When Mega Man replicates an enemy's powers, he also absorbs some of their personality. External factors sometimes cause him to switch to that personality and start unwittingly using those powers, even when not transformed.
- Teen Titans
- When Beast Boy got a cold, every sneeze caused involuntary morphing.
- When Starfire went through Tamaranian puberty, she developed a number of strange and unattractive features before returning to normal and having the ability to fire starbolts out her eyes.
- Starfire's allergy to metallic chromium also causes her to sneeze rather explosively.
- Cyborg got a computer virus. It affected his perception and personality such that he became obsessed with Waffles, and perceived everything as food. Including inappropriate and dangerous things.
- In Transformers: Beast Wars, Tarantulas infects Rhinox with a virus that makes him hiccup destructive bolts of electricity in the first season episode, "The Low Road." The episode plays pretty straight to the trope, with the other Maximals alternately nursing their new Annoying Patient and running on a Fetch Quest for the antivirus.
- Underbite is a recurring villain from Transformers: Robots in Disguise who gets stronger when he eats metal. Unfortunately, once, that metal was part of a space bridge. He spent the episode randomly teleporting to past locations every time he hiccuped.
- In Whatever Happened to... Robot Jones?, the title character is struck down by a computer virus in one episode, which presents itself similarly to a human cold (with Robot Jones sneezing oil everywhere).
- It was used as a gag in X-Men: Evolution that when Kurt had a cold he would teleport everytime he sneezed.
- Yin in Yin Yang Yo! came down with the WooFoo Flu which caused inanimate objects to come to life. She was the Annoying Patient for her brother Yang. Until he came down with it, and put Yo in the position of caretaker to the sick sibs.