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[[quoteright:350:[[WesternAnimation/CoolMcCool https://static.tvtropes.org/pmwiki/pub/images/screenshot_2022_03_15_42255_pm.png]]]]

->''"But for a real demonstration, we're pumping our studio audience full of my patented laughing gas! These yahoos will laugh at anything now, even the phone book!"''
-->-- '''The Joker''', ''WesternAnimation/BatmanTheAnimatedSeries''

Despite often being referred to as "laughing gas", nitrous oxide will not make you burst into a fit of giggles. It will not even make you chuckle. In RealLife, while it does cause relaxation it has no effect on your sense of humor, does not render you unaware of your surroundings, is only effective while being administered, and is pretty useless outside of a dentist's office, using dental equipment or a music festival, using balloons.[[note]]Recreational users of nitrous oxide often fill balloons or plastic bags with the gas. The drug is used in this way at music festivals, typically using food grade nitrous oxide sold as a whipping agent for whipped cream.[[/note]] This is not to say there isn't some truth to the name -- nitrous oxide ''does'' have a euphoric effect and a dreamy reverie when inhaled, and a large dose may even lead to trippy psychedelic experiences.[[note]]Psychedelic effects of a subanesthetic concentration of nitrous oxide. Ghoneim MM , Kumar V , and Pathak D. In ''Anesthesia Progress'', 01 Nov 1990, 37(6):271-276[[/note]] It just isn't a great idea for incapacitating or knocking
out someone.

In fiction, however, Laughing Gas is ExactlyWhatItSaysOnTheTin. It will make whoever breathes it giddy and helpless, and the effects will wear off after a certain period of time rather than stopping the instant the gas stops being administered. It'll often result in [[HelplessWithLaughter someone laughing too hard to do anything at all]]. They might even [[PottyFailure literally piss themselves laughing]]. Sister trope to KnockoutGas. Compare TranquillizerDart, which also involves characters acting giddy and saying {{Non Sequitur}}s. Subtrope of InvoluntarySmileOfIncapacitation. See also ArtisticLicenseMedicine. Often used in IWantThemAlive. Can result in LaughingMad. May overlap with DeadlyGas and DieLaughing if the gas isn't so nonlethal.
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!!Examples
[[foldercontrol]]

[[folder:Advertising]]
* At one point, evil agents kept coming up with plans to steal the secret formula for Kellogg's Sugar Frosted Flakes from Tony the Tiger. One such plan involved a FemBot tiger that would spray laughing gas at Tony when he said about Frosted Flakes, "They're grrrrrreat!", giving the robot a chance to grab the formula while Tony was HelplessWithLaughter. Just as she started to spray the gas, though, Tony accidentally hit her arm, causing her to [[AerosolSprayBackfire spray the gas at herself instead]].
-->'''Robot:''' [[MachineMonotone Ha ha ha! Hee hee hee! Ho ho ho...!]]\\
'''Tony:''' Gee. She must think I'm a real [[{{Pun}} gas]].
[[/folder]]

[[folder:Anime & Manga]]
* ''Manga/{{Naruto}}'': In episode 186 of the anime, "Laughing Shino (aka, the Funeral Proxy Mission)", Naruto and Shino are hired to go to Motoyoshi Village to stand in for Futa Kagetsu at his father's funeral. The apparent reason being that his father's will stated that, it Futa laughed at all during the funeral, he'd lose his inheritance to his sister, Tsukiko. When the three sit down to dinner, Shino volunteers to eat first since the beetles he house in his clothes will neutralize any poison that the food's been laced with. As soon has he starts, Shino snickers, which soon erupts into uproarious laughter that he spends the rest of the episode dealing with, as his beetles were apparently unable to neutralize the laughing formula in the food.
[[/folder]]

[[folder:Comedy]]
* In one of Creator/DaveBarry's columns, he talks about the safety systems aboard airplanes. When he brings up those breathing masks that drop from the ceiling panels if air pressure gets too low within the plane, he wishes that they'd dispense nitrous oxide rather than pure oxygen. Because in any situation where he needs that breathing mask (i.e., an airplane accident), he doesn't want to be fully awake and cognizant--he'd rather be laughing at the pretty flames on the cabin walls.
[[/folder]]

[[folder:Comic Books]]
* ''ComicBook/{{Batman}}'''s iconic villain [[MonsterClown the Joker]] has laughing gas or "Joker Venom" as a part of his varied arsenal. If anyone inhales or is afflicted by it, they suffer a debilitating laughing fit. {{Depending|OnTheWriter}} on the type of story (either kid-friendly or mature), how badly it affects people varies. In a LighterAndSofter story, it can just be a harmless distraction that allows the Joker to do whatever he wants while everyone is laughing their butts off. In {{darker|AndEdgier}} stories, the victims of the gas laugh so uncontrollably that [[DieLaughing they are no longer able to breathe, leaving corpses with pained smiles on their faces.]]
* In ''ComicBook/StrangeAdventures'' #36, alien invaders try to conquer the humans by converting the Earth's atmosphere into laughing gas. [[WebVideo/AtopTheFourthWall Linkara]] points out the counterproductiveness of this method in his review:
-->'''Linkara:''' [They] learn that an alien spaceship has landed and is converting the oxygen and nitrogen in the atmosphere into nitrous oxide, or laughing gas. Admittedly, I'm not a scientist, but that just seems impossible. Especially the fact that it's making them all laugh uncontrollably. It's just supposed to make you more euphoric and ''maybe'' give you the giggles before it knocks you out. Oh, here's a funny thing, I don't know if it's true or not, but Wikipedia says that nitrous oxide is actually a worse greenhouse gas and air pollutant than carbon dioxide. So the aliens are kinda screwing over the planet they're trying to conquer. Polluters from Space!
[[/folder]]

[[folder:Fan Works]]
* PlayedForHorror in ''WesternAnimation/TheLoudHouse'' fanfic ''[[https://www.deviantart.com/marvelearth19999/art/Ace-Savvy-The-Girl-Who-Laughs-911681504 The Girl Who Laughs]]'', in which Luan's evil alter ego has a gas that can make people laugh uncontrollably until they die.
[[/folder]]

[[folder:Film -- Animated]]
* ''WesternAnimation/IceAgeDawnOfTheDinosaurs'': The way to the subterranean world goes through a crevasse full of toxic fumes, which is revealed to have very similar properties to [[Franchise/{{Batman}} Joker's laughing gas]] in that it causes anyone who inhales it to [[DieLaughing laugh until they stop breathing]]. Although the laughter may not have been caused directly by the gas but by the HeliumSpeech effect, prompting the victim to start laughing at their own voice. It caused the characters who inhaled the fumes to sound like chipmunks, which they found incredibly funny.
[[/folder]]

[[folder:Film -- Live-Action]]
* Weaponized in ''Film/SixUnderground'' when the heroes use Nitrous Oxide smoke grenades to incapacitate enemy guards.
* Subverted in ''Film/Batman1989''. Unlike the gases he uses in other incarnations, Joker's Smylex gas just kills people without making them laugh first. For the chemical to actually cause a victim to die laughing, it has to be applied onto the skin in a particular combination of makeup and beauty products. It’s played more straight during the 200th anniversary parade, though.
* In ''Film/DangerDiabolik'', Diabolik and Eva disrupt a press conference held by the Minister of the Interior by releasing "[[ExpoLabel exhilaration gas]]" into the crowd (after taking "anti-exhilaration pills" to remain unaffected), which causes everyone else in the room to suffer a simultaneous fit of hysterical laughter.
* In ''Film/DoctorInClover'', Sir Lancelot and Dr. Grimsdyke bring an experimental laughing gas to the nurses' party to liven it up if need be. When Matron stops the music to complain about the alcohol in the orangeade, Dr. Grimsdyke sets it off, and soon Matron and everyone else at the party is in hysterics.
* ''Film/InspectorGadget2'': When Claw and his minions crash a party in order to steal a giant ruby, the villain releases a cloud of laughing gas that leaves the party-goers in hysterics.
* ''[[https://en.wikipedia.org/wiki/Laughing_Gas_(1914_film) Laughing Gas]]'', a 1914 short starring Creator/CharlieChaplin, has Chaplin playing a dentist who uses nitrous oxide (or laughing gas) as an anesthetic on his patients, only to end in hilarious results.
* ''Film/LethalWeapon4'' has a scene in which the guys ambush one of the Triad bosses at his dentist appointment and interrogate him using nitrous as a makeshift {{Truth Serum|s}}. Pretty soon everyone's high on the stuff, giggling like idiots and getting a little too chatty with each other.
* ''Film/TheLittleRascals'': In "[[https://ourgang.fandom.com/wiki/Wedding_Worries Wedding Worries]]", Darla (in her final short) and the boys take a tank of laughing gas out of her father's dentist office and use it to disrupt his wedding by causing wild laughter in the ceremony room.
* ''Film/ThePinkPantherStrikesAgain'': In order to infiltrate Dreyfus's castle, Clouseau disguises himself as a dentist who has come to take care of Dreyfus's toothache. He administers nitrous oxide (laughing gas) to both Dreyfus and himself, causing both of them to be overcome with laughter.
* In ''Film/ScavengerHunt1979'', Kenny, Jeff, Lisa, and Kay all start giggling and gradually laughing uncontrollably when the tank of laughing gas they nabbed (which is one of the items on the list) is accidentally opened inside the van. The cop who stops them is convinced that they're high on something, but he gets gassed himself and voluntarily gives them his uniform, another item on the list.
* ''Film/Taxi2004'': Belle and Washburn escape into another room to hide from the villains. Washburn accidentally opens a canister of nitrous oxide gas, causing the two to start laughing.
* ''Film/TheyClonedTyrone'': During their first visit to the lab, Slick Charles samples a white powder that causes him to have an uncontrollable giggling fit. Later, while discussing the mystery in a fried chicken restaurant, Charles notices him and his companions launching into similar fits before realizing the conspirators are putting the laughing powder ''in the chicken''.
[[/folder]]

[[folder:Literature]]
* ''Impy's island'' or ''Urmel from the ice'', a novel of the German author Max Kruse and its adaptation by Creator/AugsburgerPuppenkiste, features a cave with a natural source of laughing gas. This proves to be dangerous, as it not only results in uncontrollable laughter, but also causes Pumponell to accidentally fire a shot on a giant, but otherwise peaceful crab as he mistakes it for the eponymous animal he wants to hunt. This has the consequence of the cave entrance collapsing.
[[/folder]]

[[folder:Live-Action TV]]
* In an episode of ''Series/BrooklynNineNine'', Jake has a {{flashback}} to the dentist's office where he is laughing while being pumped with gas.
* Downplayed in an episode of ''Series/ICarly'' that has Sam acting loopy after being given nitrous at the dentist. She's not laughing, though -- just smiling.
* ''Series/LoisAndClark'': In "The Prankster", [[MonsterOfTheWeek Kyle]] pumps nitrous oxide through the vents after luring Lois into his trap, causing her and everyone in the building to laugh uncontrollably. He and his partner Victor then take her away.
* ''Series/NedsDeclassifiedSchoolSurvivalGuide'': In "Science Fair", one of the projects at school's science fair involves the effects of Nitrous oxide on plant life. Near the end, Ned falls and breaks the display, causing him to inhale the gas and start laughing uncontrollably. He then grabs onto a Van de Graaff generator, which makes his hair stand up and gives him the appearance of a stereotypical MadScientist.
* ''Series/RedDwarf'': In "[[Recap/RedDwarfSeasonXFathersAndSuns Fathers and Suns]]", the Dwarfers are trying to uninstall [[AIIsACrapshoot Pree]] from the mainframe when she intends to [[HurlItIntoTheSun throw Red Dwarf into the nearest sun]]. In an attempt to stop this, Pree releases laughing gas, causing the group to start laughing uncontrollably and slowing down their progress. On the upside, Kryten is able to use the opportunity to resolve the tooth problem that Lister had been having all episode.
* In one ColdOpen of ''Series/ShakespeareAndHathawayPrivateInvestigators'' that flashes back to Frank's time as a cop, he lets himself be taken hostage in an ambulance by an armed robber, and when his captor's head is turned, he discreetly opens a tank of nitrous oxide, flooding the ambulance enough that it gives Frank an opening to grab the robber's gun. He and the robber then exit the ambulance, both doubling over in laughter.
* ''Series/SisterSister'': Lisa Landry was [[LaughingMad breaking out into a fit of laughter during a funeral]] as just beforehand, she went to the dentist, and was exposed to a large, almost lethal dose of laughing gas due to the dentist ranting about the person the funeral was for.
[[/folder]]

[[folder:Theatre]]
* ''Theatre/LittleShopOfHorrors'' has the song "Now (It's Just The Gas)", in which a dentist goes LaughingMad due to an overdose on laughing gas, before he [[DieLaughing eventually suffocates on it]].
[[/folder]]

[[folder:Video Games]]
* In ''VideoGame/{{Oddworld}}: Abe's Exoddus'', laughing gas shows up as a hazard in several areas. It doesn't affect Abe, but any of his followers who breathe it in will begin running around and giggling uncontrollably, refuse to follow Abe's instructions and potentially draw the attention of [[{{Mooks}} Sligs]] or other enemies. Abe must [[GetAHoldOfYourselfMan slap them in the face]] to get them back to normal.
* ''VideoGame/StarTrek25thAnniversary'': One away mission has you needing to climb down a ladder into the room below, but some hostile Romulans are holed up in there and will disintegrate anyone who tries to enter the room. The solution is to use a device in the room you're in to mix some chemicals together to get "Romulan Laughing Gas" and release it into the air vent. This will cause the Romulans to laugh themselves unconscious and let you enter the room safely. It's also possible to make regular nitrous oxide and use that instead, but in that case Kirk, Bones, and the Redshirt will also be affected by the gas, complicating things.
[[/folder]]

[[folder:Web Animation]]
* ''WebAnimation/DeathBattle'': In "[[Recap/DeathBattleS03E05JokerVsSweetTooth Joker VS Sweet Tooth]]" and "[[Recap/DeathBattleS09E01HarleyQuinnVSJinx Harley Quinn VS Jinx]]", Joker venom is used by two combatants -- the Joker himself and Harley Quinn, in that order -- against their opponents, [[VideoGame/TwistedMetal Needles Kane]] and [[VideoGame/LeagueOfLegends Jinx]], respectively. Both Needles and Jinx are reduced to helpless deranged laughter upon exposure to the gas, but whereas Needles suffocates in front of the Clown Prince of Crime, Jinx's upbringing in the toxic undercity of Zaun means that she can NoSell the venom, instead entering an UnstoppableRage and wiping the floor with Harley.
* ''WebAnimation/TheFrolloShow'': As Frollo takes care of the bugs infesting their house "[[OverlyLongGag one by one by one (etc.)]]", Gaston accepts to buy a fumigant from Mephiles. Despite Frollo's objection, they both realize too late the fumigant is actually a laughing gas and immediately roll on the floor laughing.
[[/folder]]

[[folder:Western Animation]]
* ''WesternAnimation/BatmanTheAnimatedSeries'': The Joker has a laughing gas that can cause people to laugh uncontrollably to the point of pain or even death (the latter often thwarted by Batman's antidote injection). It shows up in several episodes, from Joker floating a barge filled with garbage laced with the stuff to poison anyone in range, to a mention in "[[Recap/BatmanTheAnimatedSeriesE51TheManWhoKilledBatman The Man Who Killed Batman]]" when he uses it to distract the police after he realizes Batman isn't showing up to the scene of his latest robbery. It can also be split into two gas components, allowing Joker to specifically target one victim to die laughing while leaving the rest unharmed as seen in "[[Recap/BatmanTheAnimatedSeriesE34TheLaughingFish The Laughing Fish]]", [[MythologyGag similar to the Batman movie]], as mentioned above.
* In the WesternAnimation/BettyBoop cartoon "WesternAnimation/HaHaHa" opens with supposedly Max Fleischer's hand drawing Betty Boop on a sheet of paper. When Max leaves the studio, Koko comes out of the inkwell for the very last time, and starts eating the candy bar Max had left on the table. Almost immediately he develops a toothache, so Betty draws a dentist room to operate on him, herself acting as the (most sexy) dentist. She first tries to pull Koko's tooth, but when that doesn't work, she tries laughing gas. The laughing gas soon pervades everything, causing not only Koko and herself to laugh, but even the clock, the typewriter, and outside in the real world, the mailbox, the cars and real people. Even a bridge and some graves join in.
* A ''WesternAnimation/ChillyWilly'' short has "Bring 'Em Back Alive" Clive attempt to catch Cilly's friend Max the polar bear with a laughing gas grenade. Unfortunately, he ends up [[ThrowThePin throwing the pin]] and leaving the grenade in his mouth, which Chilly makes him swallow by hitting him from behind. The grenade [[DinnerDeformation then goes off in the hunter's stomach]] and he feels the effects, causing him to start laughing like Woody. [[TheCameo Said woodpecker]] then shows up, irked that Clive's [[HeyThatsMyLine doing his laugh]], and pecks the ice around him so he'll fall through it.
* ''WesternAnimation/CodeLyoko'': In "[[Recap/CodeLyokoS1E15 Laughing Fit]]", Mrs. Hertz introduces nitrous oxide to the class, also calling it by this trope's name, which forces anyone who inhales it to laugh uncontrollably unless they neutralize it with water quickly. XANA takes control of the gas in an attempt to kill the heroes by making them DieLaughing, which becomes problematic when Ulrich and Yumi are at school without water to help them, Jeremie is forced to run in the sewers on foot because he can't risk staying in the freezing sewer water for too long, and Odd gets a whiff of the gas just before he's virtualized into Lyoko, which severely weakens him and leaves him disoriented throughout the crisis.
* ''WesternAnimation/CoolMcCool'': Jack-in-a-Box's weapons include grenades filled with laughing gas.
-->'''Cop:''' Ha ha ha! He's stealin' all our money!
* ''WesternAnimation/TheCrampTwins'': In "Happy Gas", Wayne, Mrs Cramp and Mr Cramp are all affected by some gas in the air that makes them unrealistically happy and unaware of their surroundings. It causes them to do silly things they would never enjoy otherwise, like Wayne willingly dressing as a girl. Lucien is the only one of his family who remains unaffected. The effects wear off near the end of the episode.
* ''WesternAnimation/DarkwingDuck'': Due to his [[WeaponSpecialization weapon of choice]] being a gas gun, the titular character usually employs this in his arsenal, though with varying degrees:
** In "[[Recap/DarkwingDuckS2E1ThatSinkingFeeling That Sinking Feeling]]", after Professor Moliarity uses a missile launcher to blast Darkwing, Launchpad, Gosalyn, and Honker into the air. Darkwing then tells Gosalyn to use his gas gun, with her firing this at Moliarity, sending him into a giggle fit and losing control of his launcher. In response to Darkwing asking WhatWereYouThinking, Gosalyn defensively says the cartridge wasn't labelled.
** In "[[Recap/DarkwingDuckS1E59TheQuiverwingQuack The Quiverwing Quack]]", after Negaduck causes Darkwing and the others to fall from a building, Darkwing inflates his cape with this to make a landing pad for them. Unfortunately, Honker, wearing an arrowhead mask, ended up bouncing upward and puncturing it, exposing all of them to the gas. Darkwing says through the giggle fit that it was better than teargas.
* ''WesternAnimation/TheFairlyOddParents'':
** [[DepravedDentist Doctor Bender]] uses this to keep kids docile while he operates on them. Timmy steals a cannister of the gas in "[[Recap/TheFairlyOddParentsS5E10ItsAWishfulLife It's a Wishful Life]]" and later uses it to incapacitate Jorgen when the latter attempts to stop Timmy from altering reality further. Later {{subverted|Trope}} when Jorgen reveals that he was fake laughing out of pity, and is [[NoSell completely immune]] to laughing gas of any kind.
** In "[[Recap/TheFairlyOddParentsS2E21FoolsDayOut Fool's Day Out]]", [[AprilFoolsPlot Timmy seeks the help of the April Fool to prank his family and friends on April Fool's Day]]. At first, Timmy enjoys the Fool's pranks, but when the Fool starts performing {{Deadly Prank}}s (such as having Timmy's parents parachute into the Broken Glass and Pointy Objects Factory with [[WrongParachuteGag pigs for parachutes]]), Timmy tells the Fool off. As retribution, the Fool tries to [[TheNightThatNeverEnds block out the sun]] and cause a new ice age, but Cosmo laughing at him before he can finish his jokes causes him to get comedy backup. If enough comedy backup builds up, the Fool will blow himself all the way back to Fairy World, so Timmy ensures that happens by wishing that all the air on Earth was filled with laughing gas. Sure enough, the laughing gas causes everyone in the world to laugh and sends the Fool back to Fairy World, foiling his plan.
* ''WesternAnimation/LooneyTunes'': In "Hot Cross Bunny", a doctor chases after WesternAnimation/BugsBunny and douses him with laughing gas from a CartoonBugSprayer. It causes Bugs to go on a laughing fit as the doctor carries him back to the operating table. Bugs briefly stops laughing when he sees some sharp surgical instruments... only to then laugh even harder.
* In ''Listen Out Loud'', an official podcast based upon ''WesternAnimation/TheLoudHouse'', Rita (a dentist's assistant) gives her daughters Lori and Lola, and her husband Lynn Sr., checkups. However, some laughing gas spills, causing the four of them, plus Lola's twin sister Lana, to laugh uncontrollably.
* ''WesternAnimation/TheSimpsons'': In the ''Macbeth'' segment of "[[Recap/TheSimpsonsS20E20FourGreatWomenAndAManicure Four Great Women and A Manicure]]", Homer uses laughing gas on Dr. Hibbett. He dies of laughter after he can't open a window and failed to call for help.
* ''WesternAnimation/WhatsWithAndy'': In one episode, when [[ThePrankster Andy]] is forced to get a job, everyone he takes he gets fired from when he sees an opportunity to pull pranks and takes it. The final one is set in a retirement home, where we see all the senior residents laughing uproariously, and Andy being chased out of the building by a nurse.
-->'''Nurse:''' Putting laughing gas in the oxygen tanks of our senior citizens is not funny! You're fired!
[[/folder]]

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