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[[quoteright:350:[[WesternAnimation/RabbitOfSeville https://static.tvtropes.org/pmwiki/pub/images/rabbit_of_seville.jpg]]]]

->''"M is for Minoxidil,\\
A hair-raising drug;\\
Takes a year to grow fuzz--\\
Give it up! Buy a rug!"''
-->-- ''Magazine/{{MAD}}'', "The ABC's of Drugs"

It seems that a man's greatest fear is losing his virility...er, hair, and once it's gone, it's gone for good. Which is why a bald character is bound to try using some kind of product that promises to grow back their hair. [[ExactlyWhatItSaysOnTheTin This product never works]]. Or rather, it usually [[GoneHorriblyRight works too well]], with way [[RapidHairGrowth more hair sprouting than necessary]], and often in places that it wasn't wanted. Other side effects may occur as well, including, but not limited to, the hair turning an unnatural color or what little hair was left falling out completely.

TruthInTelevision: most over the counter baldness remedies ''don't work or don't work well'', especially when used once the condition is sufficiently advanced. Prescription systemic treatments are somewhat more likely to work (though they also come with bad side effects for men — namely, they work by reducing testosterone and/or its effects on the body in most cases). The gold standard of baldness treatment is hair transplant with ongoing maintenance, as it is the most likely to actually be worth the money spent on it with the least systemic side effects.

For similar forms of hair-related hilarity, see MyHairCameOutGreen and occassionally KaleidoscopeHair. See also AllNaturalSnakeOil for the same principle applied to more serious ailments, not usually played for laughs. Compare BaldnessAngst and FirstGrayHair, which might make people turn to the untrustworthy hair tonics.
----
!!Examples:

[[foldercontrol]]

[[folder:Advertising]]
* In a fake ad that is interrupted by the Advertising/EnergizerBunny (the actual product being advertised), a man hawks a hair tonic that's way too ''effective'': it causes hair to sprout not just on his head, but also on his back when the excess spills and even on the concrete pool surface when the Bunny knocks the bottle over.
[[/folder]]

[[folder:Anime & Manga]]
* An early ''Manga/InuYasha'' story has two demon brothers kidnap Kagome. She thinks they simply want to eat her, but it turns out one of them is severely balding and embarrassed about it, and he has heard you can get a hair growth potion by ''boiling down a human maiden''. At hearing this, Kagome angrily insists they eat her instead. (Not 100% really this trope, since we never learn whether the potion works -- but the kidnapping does lead to the demon losing his last few hairs -- before he is killed.)
* ''Manga/NegimaMagisterNegiMagi'' has a female variation, when short-haired Ako thinks she should grow her hair out to be more attractive. A (not so) helpful denizen of the magic world promptly gives her a magic hair-growth potion, which works perfectly for all of a minute before the hair begins to engulf her.
* On ''Manga/RanmaOneHalf'' Genma is quite embarrassed about his baldness and has tried all kinds of cures. This doesn't stop him from trying new remedies. There was the one that only works when he's angry, the one that comes from a one-of-a-kind dragon's whisker, and so forth.
* In the gag manga ''Manga/UrayasuTekkinKazoku'', 43-year-old Daitetsu Osawagi has a bald spot and fearing of becoming completely bald like his father. A RunningGag had him losing hair by force, such as laying unconscious on an escalator and pulling off a glued wig. Chapter 51 in the ''Ganso'' series showed him losing faith in his hair tonic dumping every bottle in his hair-clogged sink. The tonics cause hair in the sink to grow out of control and start to consume Daitetsu and the house.
[[/folder]]

[[folder:Comic Books]]
* In an ''ComicBook/AchilleTalon'' comic strip, Achille tries multiple ways to cure his baldness, all of which turn out to be ineffective. His last attempt is a hair tonic that is revealed to work very well -- too bad he accidentally falls into it, covering him of hair everywhere ''except'' on his scalp.
* In an ''ComicBook/ArchieComics'' comic, Professor Flutesnoot invents a hair tonic which apparently does a great job growing one's hair back. Though he stresses that he's still testing it, Mr. Weatherbee insists on secretly using it on himself. By the end of the comic, it's revealed that the tonic makes one grow a freakish amount of hair, with pouring water on it being the only way to stop the process.
** In another comic, Jughead has created a hair tonic and tested it on a cue ball. Weatherbee gets it of course, and pretty soon has a headful of hair again. Flutesnoot then reveals that he analyzed Jughead's formula, and that a key ingredient is swamp muck; Weatherbee has a headful of ''moss''.
** An issue of the comic book adaptation of ''WesternAnimation/ArchiesWeirdMysteries'' has it that [[BigfootSasquatchAndYeti bigfoots]] converts humans into more of them by convincing them to use an ointment that makes their hair grow before transforming them fully. The substance constantly replenishes, and compels them to both keep using it and convince others to use it.
* An issue ''ComicBook/BartSimpson'' has him stealing a powerful hair growth formula from Professor Frink to prank everyone with. This is after finding out that he's genetically immune to its effects, which he exploits both to handle it without protective gear and as part of the delivery mechanism.
* A ''ComicBook/DisneyDucksComicUniverse'' comics story "Black Wednesday", written by Creator/CarlBarks, features Uncle Scrooge selling hair tonic to the "Chillyboot Indians", which actually causes baldness. Donald later returns with a hair tonic made by Gyro Gearloose; that one works too well.
* ''WesternAnimation/TheGrimAdventuresOfBillyAndMandy'' story "Nose No Bounds" (''ComicBook/CartoonNetworkBlockParty'' #41) has Grim letting Billy use some otherworldly hair tonic. He inhales it, and it causes his nose hairs to grow and gain sentient life.
* In ''ComicBook/TheSmurfs'' story "The Great Smurfette", Gargamel was reported to have given a bald person a potion for growing a full head of hair, but the side effect is that it has given the person a chronic case of incurable hiccups.
* One issue of Atlas comics had a balding man try out an experimental formula invented by his barber. It's successful, but with the unintended side effect of giving the man, a 90 pound weakling, super strength and invulnerability. Tiring of his newfound attention, he pretends to have lost his powers, then shaves his head and pretends to the barber that it didn't work.
* Played with in ComicBook/{{Dollicious}} Lasagne and Bow by acident put Ramens hair tonic into a tomato soup... Since Ramen hair is made out of noddles, the noddles in the soup grows into Jack and the Beanstalk-style noddle stalk all the way to heaven.
[[/folder]]

[[folder:Comic Strips]]
* One ''ComicStrip/BloomCounty'' arc features a compound made from cat sweat, which [[MadScientist Oliver]] originally intends as an underarm deodorant, but causes massive hair growth wherever it's applied. Oliver immediately turns it into a hair tonic instead. Sales are ridiculously, dangerously good for a while... and then customers start going "ACK!", presumably because it's made from Bill the Cat's sweat, this being his VerbalTic. In a coda, Oliver's dad (a long-term user) sneezes one morning and causes all his hair to fall out instantly.
* It's happened a few time in ''ComicStrip/{{Curtis}}'', often thanks to the titular character's misuse of a Flyspeck Island substance.
* ''ComicStrip/DreamOfTheRarebitFiend'': [[http://www.comicstriplibrary.org/display/912 A balding man has a dream]] where he's using a hair tonic to restore hair to his shiny dome. It winds up working too well, and the now extremely hairy man becomes a sideshow attraction.
* ''ComicStrip/TheYellowKid'' once used a new miracle hair tonic to turn his robe into a fur coat.
[[/folder]]

[[folder:Film — Animation]]
* In ''WesternAnimation/CloudyWithAChanceOfMeatballs'', one of Flint's [[BunglingInventor failed inventions]] is "Hair Unbalder." A little bit squirted on the scalp causes his dad to burst out with hair on his entire face.
* Similarly, some hair-voodoo worked by Dr. Facilier in ''WesternAnimation/ThePrincessAndTheFrog'' initially grants a man a full head of hair, but it quickly spreads to the rest of his body. In this case, it's not a potion but a magical powder Facilier blows in his face. [[ForTheEvulz Given Facilier's evil chuckling at this afterward, it was obviously deliberate rather than an unfortunate side effect]].
* In ''WesternAnimation/TheSpongeBobSquarePantsMovie'', King Neptune tries to use some hair tonic, but accidentally it gets into his eye. [[EyeScream/SpongeBobSquarePants So his eyeballs grow hair]].
[[/folder]]

[[folder:Film — Live-Action]]
* ''Film/BodyBags'': In the "Hair" segment, a balding guy goes to a new clinic to get an experimental hair transplant. It works, but then his hair keeps growing all over his body. At one point he even has to pull a new hair out of ''his tooth''. [[spoiler:It turns out the "hair" are really spindly aliens who want to eat his brain.]]
* While demonstrating his experimental candies to the guests in ''Film/CharlieAndTheChocolateFactory'', Wonka brings up a gum intended to grow hair that he's working the kinks out of. We're shown an Oompa Loompa who tested a piece, who walks up looking like Cousin Itt.
* In ''Film/TheNakedGun 33 1/3'', there's a flashback with the detectives in what's supposed to be the 1970s. Drebin has long hair, and when Nordberg appears, he has an Afro so huge he can't fit through the door. After the movie returns to the present, Ed says to Nordberg, "I do remember! You were one of the first cases for minoxidil." [[note]]Minoxidil is probably best known to the general public under the name Rogaine.[[/note]]
* In the Canadian family film ''Film/ThePeanutButterSolution'', a boy loses his hair after seeing ghosts, then grows it back with the titular solution. It works only too well. Unfortunately, he used too much peanut butter making it, so it won't stop!
* In ''Film/PetesDragon1977'', when [[SnakeOilSalesman Dr. Terminus]] comes to town, the townspeople confront him about his various medicines that didn't work the last time he was there, including one man whose hair turned from gray to pink, thanks to the doctor.
[[/folder]]

[[folder:Literature]]
* In ''Literature/CharlieAndTheChocolateFactory'', one of the works-in-progress in the Inventing Room is Hair Toffee, which gives its eater a full head of hair plus a mustache and beard, a half hour after it's consumed. It's still a work in progress because currently it's too powerful -- when an Oompa-Loompa tested it, "In the end we had to use a lawn mower to keep it [the hair] in check!" according to Willy Wonka. Also, it apparently has the same effect on men ''and'' women, and even works on children -- which is his intention, in order that "there'll be no excuse any more for little boys and girls going about with bald heads!"
* In ''Literature/TheCityOfSilentRevolvers'', the main character is blackmailed into switching identities with a conman, and ends up getting in trouble for all of his earlier scams. A faulty hair tonic called Probatbicol is one these scams.
* In the ''Literature/{{Discworld}}'' short story "The Sea and Little Fishes", when Granny Weatherwax is experimenting with being nice to people, she gives one bald farmer a bottle of hair tonic. He decides to test it on the dog; unfortunately he's too worried to read the instructions and gives it a overdose. When a group of peasants petition Nanny Ogg to tell Granny that WeWantOurJerkBack, they report that the entire family is currently spending all their time shearing the dog.
** A variant in ''Literature/{{Jingo}}'' with the character "Snowy" Slopes (who's not an assassin; [[DistinctionWithoutADifference he just kills people for money]]) and his terrible dandruff, which he resorts to various forms of AllNaturalSnakeOil to cure and ends up being identified as a suspect because of them. None of them ever worked.
* In ''[[Literature/DanShambleZombiePI Hair Raising]]'', Dr. Victor is determined to invent a hair tonic that will subvert this trope. [[spoiler: He succeeds in creating one that grows hair, but it won't ''stop'' growing it ... even when the hair in question is clogging up the shower drain.]]
* Crocodile tears in the book ''Literature/HubertsHairRaisingAdventure'' by Bill Peet. The zebra notes that crocodile tears might help Hubert regrow his mane. Getting them proves enough of a problem...and then the tears cause the mane to grow so long so fast that it winds around Hubert and the other animals. They have to call a baboon with some shears to cut them loose.
* The title character in ''The Witch's Son'' by Vivian Van Velde goes through several variations on regrowing a girl's golden hair, [[HilarityEnsues none of which work.]]
[[/folder]]

[[folder:Live-Action TV]]
* In the ''Series/BetterOffTed'' episode "Father Can You Hair Me?", Ted tests an experimental hair tonic (packaged as an aerosol) on his arm, causing massive amounts of hair to grow not only on Ted's arm, but also on his desk.
* In (what turned out to be) the final episode of ''Series/TheBradyBunch'' Bobby gets some mail-order hair tonic to sell, which turns Greg's hair orange. In the [[http://jonrowe.blogspot.com/2004/11/my-sense-of-humor-my-best-friend-david.html memo]] attributed to Robert Reed about how weak the show's internal logic had become, he complains about this in particular:
-->Why any boy of Bobby’s age, or any age, would be investing in something as outmoded and unidentifiable as “hair tonic” remains to be explained. As any kid on the show could tell the writer, the old hair-tonic routine is right out of ''[[Film/TheLittleRascals Our Gang]]''. Let’s face it, we’re long since past the “little dab’ll do ya” era.
* In a DreamSequence on ''Series/TheDickVanDykeShow'' Rob's hair turned into lettuce, because he was given a baldness preventative[[note]]as opposed to cure -- he had hair, he was just worried about losing it[[/note]] that was basically oil and vinegar -- aka salad dressing.
* ''Series/DoctorWho'': In [[Recap/DoctorWhoS30E3PlanetOfTheOod "Planet of the Ood"]], Mr. Halpen, the balding head of Ood Operations, is constantly drinking hair tonic given to him by his personal Ood servant, Ood Sigma. [[spoiler:It's actually Ood graft which eventually [[KarmicTransformation transforms him]] into the very species he had been enslaving.]]
* A ''Series/GoodEats'' episode on celery has a sketch of a celery drink just made regrowing hair, then shows Alton paying the man whose hair supposedly grew back in private.
* One early episode of ''Series/MarriedWithChildren'' had Al and Steve freak out about their baldness and try an experimental "tonic" to reverse it. Not only did it not work, but Al's dog Buck took to the stuff better than their hair did [[spoiler:(they were actually using some kind of dog food in their hair, and the doctor who sold it to them was a quack)]].
** Another episode features an accidental hair tonic made by the daughter experimenting with paint. It works wonders, but has the nasty[[labelnote:*]]by Al Bundy & Co's standards, obviously[[/labelnote]] side-effect of [[spoiler:[[LovePotion making the users horny for their wives]]]].
* ''Series/MyWifeAndKids'': In "The Sweet Hairafter", Michael's friend Jimmy has a hair-growth pill that makes him paranoid. Once Michael starts to take the pills, he displays the same symptoms.
* ''Series/{{Seinfeld}}'': George Costanza's Chinese baldness cure. We never find out whether or not it actually works, because it smells horrible and [[ItMakesSenseInContext he recently developed a crush on Elaine]], so he rushes to wipe it off whenever she comes around.
* ''Series/TwoAndAHalfMen'' feature 'Captain Terry's Spray On Hair' as well as pills, both of which Alan try before going on dates. The first ends up running down his face when warm and the pills cause bizarre follicle growth.
* ''Series/TheTwoRonnies'' did a skit at an inventors' conference, one of the inventors had created a hair tonic with two problems. First it makes the hair grow pink and second is that it falls out if the drinker has a shock.
[[/folder]]

[[folder:Theatre]]
* Pirelli's Miracle Elixir from ''Theatre/SweeneyToddTheDemonBarberOfFleetStreet'', which turned out to be, in Sweeney's words, "an arrant fraud, concocted of piss and ink."
[[/folder]]

[[folder:Video Games]]
* ''VideoGame/LISAThePainfulRPG'': Hair tonics can be equipped as headgears for bald characters. Their descriptions say they never work "but it helps to dream".
* ''VideoGame/PhantasyStarZero'': One of the first sidequests available comes from Major Dairon. He asks the hunter to retrieve some special flowers found in the Gurhacia Valley. It is later revealed he plans to use them in a tonic to stop his thinning hairline from getting worse. It didn't work and the concoction stank to high heavens.
* Conroy Bumpus of ''VideoGame/SamAndMaxHitTheRoad'' uses so much hair tonic that his pillow is completely drenched with the stuff. He also wears a toupee all the time, so it seems the tonic doesn't work on him.
[[/folder]]

[[folder:Web Animation]]
* Used for {{squick}} factor when Disco Bear from ''WebAnimation/HappyTreeFriends'' dunks his head in hair tonic after burning his afro. His hair grows back... but in his eyes. Cue EyeScream when he cuts his eyes off with a razor as he tries to remove the hair from his eyes. He slips on a bottle of hair tonic and falls to the tub of hair tonic and grows more hair.
** And not just Disco Bear, Cuddles coughs out his hairy organs before choking to death after mistakenly drinking a bottle of the formula that fell into his soda cooler and a bottle bursts open on Flaky while driving, causing her spines to impale her passenger, Handy.
[[/folder]]

[[folder:Webcomics]]
* ''Webcomic/DocRat'' featured Mr Pigg complaining to the chemist that the tonic he'd purchased which promised to "add body to your hair" had caused him to sprout hair everywhere. Turned out he'd read the label upside down; it actually said "adds hair to your body".
* ''Webcomic/PvP'' had a storyline where Brent cuts off his ponytail to prove that he's just as confident and hip without it. Obviously, this quickly backfires, and he desperately tries to get his hair back, leading to Skull giving him a hair growth potion. Unfortunately, Brent uses up most of the bottle, which was supposed to be diluted in water first, and he immediately grows hair so long he looks like [[Franchise/TheAddamsFamily Cousin It]], including [[BodyHorror on his hands]].
--> '''Brent''': My scalp feels tingly...
[[/folder]]

[[folder:Web Original]]
* ''Website/GaiaOnline'' has an item called Gro-gain: "New and improved, all natural formula guarantees DRAMATIC new hair growth, or your money back!" It can give you a huge mustache on your crotch, "Coiling Pit Hair", "Unforgivable Leg Hair", "Evil Hair" on your head, and more. It can even turn you into a "Fearsome Hairy Beast". It even caused a child character to develop a CasanovaWannabe alter ego and experience RapidAging.
* The ''Website/SCPFoundation'' had a [[http://scpclassic.wikidot.com/scp-491 hair tonic]] which caused its users to be "completely torn apart from the inside by torrential amounts of internal hair growth."
** There's also [[http://www.scp-wiki.net/scp-3802 "hare growth by dado,"]] made by an... [[LiteralMinded interesting]] pharmacologist at the request of a parent whose daughter lost her hair to chemotherapy. It actually does [[ExactlyWhatItSaysOnTheTin what the name says it does]], but that typo isn't there by accident (and [[BodyHorror God help you if you're not a child]]).
* Hazmat of the ''Literature/WhateleyUniverse'' is cueball-bald due to his failed hair tonic. Aquerna arranges for Phase to look at it and plans are put into place to sell it as a hair-removal application for women.
[[/folder]]

[[folder:Western Animation]]
* In an episode of ''WesternAnimation/AaahhRealMonsters'', a prank gone wrong causes Krumm to lose his armpit hair, and Ickis, looking to help out his buddy, comes across some Super Grow Hair Tonic (thrown out in the dump by a scientist who thought the tonic was useless since he didn't grow hair on his bald head the second he rubbed the tonic on it) and uses eleven bottles of the chemicals to regrow Krumm's armpit hair, which ends up growing longer to a point where it is now grown all over the dump.
* ''WesternAnimation/CourageTheCowardlyDog'':
** In the episode, "Hothead", Eustace applies for an experimental hair tonic, with the warning that the recipient not be angry when in use. Little does Eustace know, is that every time he uses the tonic, it amplifies his anger to the point that he can cause explosions (and to add insult to injury, he doesn't grow any hair other than one long strand at the end of the episode, which immediately wilts again, making him so angry he blows up the house with himself inside it, Courage escaping with Muriel at the last moment.)
** Another episode has Eustace's mother be involved in human experimentation for various hair related products. The twist here is that their method DOES work, extremely well in fact, causing people to grow huge amount of hair to be used in experiments. At the end, after Courage has freed Muriel from her unwilling participation, Eustace returns to the farm, now ''covered'' in a thick head of hair, and holding fistfuls of cash for his participation. This is pretty much the high point of Eustace's life on the show.
* In ''WesternAnimation/DextersLaboratory'', Dexter makes a hair tonic for Dee Dee after she accidentally cuts off one of her pigtails. Despite repeated warnings to use only one drop, Dee Dee uses the entire bottle. Three guesses what happens next.
--> '''Dee Dee''': I ''did'' use one drop, just... [[ExactWords a very big drop]]...
* A ''WesternAnimation/FreakyStories'' story involves a boy inventing a hair tonic that, while capable of growing hair on any surface, doesn't seem to work on him. After dousing himself with it in a panic, he realize all to late that it takes longer for the tonic to grow hair on a human, and it turns him into a werewolf.
* ''WesternAnimation/{{Gasp}}'': In "Hair of the Fish", Gasp buys a Peruvian hair tonic online in an attempt to cure the bald patch he accidentally created on Catflap. After he is doused in the tonic, Gasp ends up growing hair all over his body. Gasp, it should be pointed out, is a fish.
* ''WesternAnimation/GetBlake'': In "Get Hairy!", Blake and Mitch use an experimental hair growth formula invented by Mitch's dad to grow moustaches so they can get in to a see a scary movie. The next morning, they try to shave off the moustaches only to discover that Mitch had not read the label and it was actually a 'Never-Ending Hair Growth Formula'. Their entire bodies end up covered in hair, causing them to be mistaken for sasquatches.
* An episode of ''WesternAnimation/TheGrimAdventuresOfBillyAndMandy'' has Billy purchase a hair growth product because he wants to have a beard. Nothing happens at first so Grim uses his scythe to supercharge the product. Unfortunately, not only does he overuse the potion on himself, he ''drinks it'' as well! He soon grows a large beard, which turns into a Bigfoot pelt. Billy is fine with this... [[BodyHorror until he grows hair on his tongue as well]].
* ''WesternAnimation/{{Grojband}}'': In "Hair Today, Kon Tomorrow", Kon uses a hair tonic (intended for dogs) that causes him to become completely covered in hair. A blow to the head then gives him DelusionsOfDoghood.
* An episode of ''WesternAnimation/HiHiPuffyAmiYumi'' had Kaz ordering a hair tonic to overcome his male pattern baldness, and it ends up frequently turning him into a werewolf who terrorizes the girls' cats. The cats later take the tonic themselves to use it against Kaz, and when Yumi finds the smashed tonic bottle she points out these kinds of products usually have side effects; in this case, Kaz and the cats have all of the hair on their bodies fall off.
* ''WesternAnimation/JohnnyTest'' has this happen due to a couple of Susan and Mary's inventions. The Zoomer Groomer could create mustaches and worked as advertised, but Bling-Bling Boy overused it, became ''very'' itchy, and grew thick hair all over his body. Another episode had Susan and Mary use a hair tonic which [[GoneHorriblyRight worked too well]], eventually leading to them looking like a woolly mammoth.
* In the ''WesternAnimation/LooneyTunes'' short "WesternAnimation/RabbitOfSeville" Bugs Bunny rubs and sprinkles a number of tonics (including fertilizer) on Elmer Fudd's scalp, only for flowers to sprout from his head instead of hair. On the other hand, the hair tonic he used earlier in the same short to grow him a beard worked perfectly.
* The ''WesternAnimation/MotherGooseAndGrimm'' cartoon had a hair tonic which could grow hair on billiard balls, as advertised...but it couldn't grow hair on anything else.
* ''WesternAnimation/MyLittlePonyFriendshipIsMagic'': In "[[Recap/MyLittlePonyFriendshipIsMagicS7E20ItIsntTheManeThingAboutYou It Isn't the Mane Thing About You]]", when Rarity loses most of her mane in an accident involving misuse of a powerful magical cleaning product and tries to grow it back, it turns out that hair magic is ridiculously hard to use. When Twilight Sparkle and Starlight Glimmer (two of the setting's most powerful magic-users) try to use magic to restore Rarity's hair, the first spell they try takes the hair from another pony and transfers it to Rarity (before said hair simply shatters), the second creates wooden hair from a chunk of a door, and the third causes long hair to appear on the castle's walls.
* ''WesternAnimation/PhineasAndFerb'' has a female example in "Bad Hair Day", when Candace uses a machine her brothers built for her in order to fix her hair after a botched attempt to cut it herself. Of course, she can't wait the designated time and decides to [[OvenLogic turn 30 mins into 10 seconds by cranking up the power level]]. Cue Candace getting covered in hair and being mistaken for a tangerine orangutan.
* ''WesternAnimation/RegularShow'' episode "Bald Spot" depicts this straight. Muscle Man purchases a hair tonic that supposedly hides his bald spot, [[spoiler: which is later revealed to be an accidental haircut near the end]], only for said substance to leak off of it.
* ''WesternAnimation/TheSimpsons'' uses this trope twice.
** In the episode "Simpson and Delilah", "dimoxonil" actually ''does'' grow hair on Homer's head, but the SnapBack to baldness comes because Bart spills Homer's bottle[[note]]splashing it on his face in hopes of growing a beard[[/note]] and he can't afford any more (mainly because the dimoxonil cost Homer 1000 dollars, which he could only afford by [[InsuranceFraud lying about his medical insurance]]). There's also the affordable tonic the doctor offers Homer because he can't afford the 1000$ dimoxonil, which the doctor even states that any hair growth Homer would experience while using it would be purely coincidental.
** At the end of the episode "Barting Over" Homer acts in a commercial for Viagra-gaine, a drug that "gives you hair and what you need down there" and has side effects including loss of scalp and penis.
* Gargamel and Brainy learned this lesson the hard way in ''WesternAnimation/TheSmurfs'' episode "Symbols of Wisdom" when they both try to grow their own beards, since it caused their beards to grow so long. Also, Papa Smurf had Hogatha's hair spell in "Smurfette's Golden Tresses" purposely altered by giving her bear fur dyed in the color of Smurfette's hair, which caused the hair to grow so long on Hogatha's head that it covered her face and immobilized her.
* A running gag subplot in an episode of ''WesternAnimation/TotallySpies'' involved their balding boss Jerry experimenting with hair growth potions. They work in making hair grow but fail in making it grow ''anywhere'' but the top of his head where he wants it. At one point he excuses being late because one variation sprouted long locks on the ''soles of his feet''.
** Eventually, Jerry would later find success in ''WesternAnimation/TheAmazingSpiez'' A villain of the week was part of a trial for a hair growth formula, and ended up covered in hair. Seeking revenge, she weaponizes the formula, which can grow hair on seemingly ''any surface'' to similarly disfigure those who ran the trial. Jerry gets some and uses it to give himself a voluminous pompadour at episode's end.
* In the ''WesternAnimation/VictorAndValentino'' episode "It Grows" an envious Victor steals a hair growing tonic that Maria Teresa uses to [[MundaneUtility reset a haircut she doesn't like to have it redone]] so he can grow a mustache. The mustache is alive, prehensile and independent, and it wants more of the tonic to grow a lot more.
[[/folder]]
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