Psycho Serum



""It's a potion I've invented where, when the patient drinks it, he turns into a axe-wielding homicidal maniac. It's basically a cure... for not being an axe-wielding homicidal maniac! The potential market's enormous!""

- Vyvyan, The Young Ones

Super Serum with some unpleasant side effects, most commonly insanity. The Psycho Serum could be the result of questionable government programs Gone Horribly Wrong or freak lab accidents; the user might be unaware of the side effects... or just doesn't care. Consequences include, but are by no means limited to:


 * Recurring and persistent addiction.
 * Physical dependence.
 * Insanity.
 * Evil.
 * New appendages.
 * Anti-human tendencies.
 * Rebelliousness.
 * Murderous rage.
 * Psychic Nosebleeds.
 * Meltdowns.
 * Lower life expectancy.
 * Harmful Healing.
 * Tainted Veins.

Since the idea is that it makes one more likely to be victorious (usually in battle) despite the above, it's closely associated with the concept of Race To The Bottom.

This item is available in the Trope Co Catalog

Anime & Manga

 * The titular chemical warfare agent in MW has effects that turned Michio Yuki Ax Crazy.
 * Ichigaki in Yu Yu Hakusho, arguable considering he was already a Complete Monster, albeit an ineffective one.
 * Cowboy Bebop has the Red Eye serum, which speeds up reflexes to superhuman levels and allows perception in Bullet Time. However, withdrawal causes vomiting, trembling, and bloodshot eyes, hence the drug's name. Julia proudly displays Red Eye paraphernalia on her windowsill. Asimov Solensan uses a high-grade variant when flying high-speed spacecraft.
 * Use of the B303 Devilfish of Eureka Seven requires the wearing of a painful-looking apparatus on the head that shoots reflex-enhancing drugs straight through your sinuses. It is stated to be outright required in order to humanly operate the machine, which has no performance limiters, or defense for that matter. For obvious reasons it's mentioned not-so-subtly that this is something you would not want to use on a regular (let alone semi-regular) basis.
 * Also, Anemone takes - or is forced to take - injections of some sort of Psycho Serum for piloting TheEnd, which suppresses her headaches but makes her psychotic and vicious. She quits it by the end of the series.
 * Akira likewise has super drugs that either give Psychic Powers or kill the user messily, the latter being the more common result. Tetsuo is dependent on these at first but gives them up after discovering that they dampen his potential.
 * The Dark Spores from Digimon Adventure 02 might qualify for this.
 * In Black Cat, one minor character drank the Tao juice, allowing him to access a superpower. For him, he could increase his muscle mass drastically, eventually being able to block bullets with his biceps. When he comes across the heroes, he loses, and returns, putting his whole being into increasing his muscles. He dies from using too much energy, and degenerates into a shriveled husk.
 * BLACK BLOOD. ENOUGH FRICKING SAID.
 * Well...it covers insanity (and by this universe's extension, alas, evil), addiction, theoretically shorter life expectancy, and super-powered evil side.
 * Insanity and evil are only synonymous in the Anime. In the manga, madness is handled differently.
 * Gasaraki has the Eyeglobulum, which when injected into a person give them the same quantum abilities as Yushiro, enhancing the way they pilot their Mecha, however as a side effect which always occurs, namely that said person will quickly turn psychotic, adopt animalistic behaviour and have psychic nosebleeds, with a 25 percent chance of lapsing into a coma and a 50 percent chance of dying from cardiac arrest.
 * Witch Hunter Robin has a green liquid that prevents military meninblack from being harmed by witch powers... until they go insane/scream/flip out.
 * Mobile Suit Gundam SEED has Gamma Glipheptin, a stimulant given to the Earth Alliance's enhanced pilots that boosts their stamina and reaction speed, but has horribly painful withdrawal symptoms (and since only the Alliance can make it, the pilots can't defect). The chemical is the primary reason for the trio's Fan Nickname "The Druggies".
 * A modified version appears in Mobile Suit Gundam SEED Destiny. By this point, the drug has been refined to the point where it takes a full days' withdrawal to kill the user, and not the few hours from SEED. The results are Super Soldiers who while less powerful than the original trio, are saner, and thus able to follow orders and go undercover more effectively.
 * The Euphoric Virus in Speed Grapher is essentially this, given that when the Big Bad contaminates products with a strain of it, the murder rate in Japan skyrockets. At least in the case of the hero and Big Bad, overusing Euphoric powers has negative impacts, and while it's ambiguous whether it actually drives you insane (it's averted with The Hero, Big Bad, and The Dragon), if you're crazy to begin with, it makes you crazier.
 * Orochimaru of Naruto created this effect in his finalized curse seal. When activated, it releases an enzyme into the user's body that greatly enhances strength, speed, and chakra levels even before activating the second stage's horrific transformation.
 * Side effects include near-berserker aggressiveness, rapid chakra depletion, and insanity given prolonged usage. A rare side effect may cause complete disintegration of body while still alive. Nine of ten recipients note cases of sudden death due to curse seal application. Curse seals are not for everyone; don't check with a doctor as Orochimaru will give you one anyway.
 * The E.S.S. drug of One Piece grants incredible power

Card Games

 * In the CCG Magic the Gathering, most Red/Black creature enhancing abilities tend to take this route. Take, for example, the flavor text of Brute Force, the reimagining of Green's iconic Giant Growth: "Blood, bone, and sinew are magnified, as is the rage that drives them. The brain, however, remains unchanged -- a little bean, swinging by a strand in a cavernous, raving head."
 * Can't forget the classic Unstable Mutation. +3/+3, but takes a cumulative -1/-1 penalty every subsequent turn -- and Defence 0 means death.

Comicbooks

 * Batman villain Bane used the drug Venom to boost his already considerable strength to titanic levels but eventually withered into a coma from overuse.
 * And predating Venom is the "Monster Serum" made by Hugo Strange, first in the Golden Age, but eventually re-introduced into modern comics. The subject becomes larger and more powerful than Bane; the Golden Age version made Monster Men strong enough to tear out elevated train supports, but reduces the subject's mind to little more than that of the stereotypical caveman's.
 * Another Batman villain, Scarecrow used fear gas that exploited the target's phobias, driving them mad.
 * Not really relevant, as that's the result he was going for, not a side effect of getting them super...
 * Probably applies to the drugs he was unknowingly given to transform him into "Scarebeast", a hulking monster with a vicious mentality. When he returns to normal he doesn't remember what happened.
 * Deadpool is a Marvel Comics example. Originally Wade Wilson, a mercenary dying of cancer, he elected to be given an artificial healing factor to help cure his cancer. It didn't work all that well. He received a healing factor but as a side effect his cancer got turned Up to Eleven, meaning that his entire body is constantly in flux between being eaten by cancer and being healed. Also the process seems to have left him very, very, very insane, though he would consider that a benefit.
 * Hourman from The DCU used the drug Miraclo to gain superpowers for one hour, overused it, and became addicted. Though he's since beat the addiction, he continues to fight crime with the drug, constantly battling his old habits.
 * While the original Mr. Hyde in the classic story was not originally a super-power drug, Mr. Hyde of The League of Extraordinary Gentlemen is.
 * It's rather more complex than that. An element of the classic story was that Hyde got stronger as Jekyll got weaker (Hyde's drives give Jekyll strength, while Jekyll's morals only restrain Hyde). By the time of the first League book, Hyde is a superpowered ogre because Jekyll is reduced to a sickly, emaciated wreck.
 * Members of Weapon X and related programs in the Marvel Universe were subjected to this to enhance their strength, stamina, and government-instilled psychoses. As Nuke says, "Gimme more reds! More! MORE REDS!!!!"
 * Subverted Trope in Nuke's case; the "Reds" and "Blues" are.
 * The Green Goblin's juice seems to cause dissociative identity disorder.
 * In Ultimate Marvel, Bruce Banner's attempt at recreating the Super Soldier serum turns him into the Hulk, then Pete Wisdom's attempt to do the same leaves him with Psychic Powers at the expense of having a head too heavy for his neck.
 * Empowered has a variant -- Mayfly gives you Mad-science level genius, at the cost of filling your brain with tumors that kill you within forty-eight hours. And that's only when it works -- which is point two percent of the time. Mostly it just kills you.
 * FX 7 in No Hero is based off of a psychedelic drug already. So, not only does it give you super powers but it makes you have living nightmares and many of the Levelers had to get into Downers to counter the drug. Oh yeah, there's also a chance that it could make you explode when you first take it.
 * Daniel Clowes parody of Captain America (comics), "The Battlin' American" goes through heroin-like withdraw symptoms if he doesn't get a regular dose of supersyrum.
 * This is primarily why attempts to reproduce Prof. Erksine's work in Project Rebirth that created Steve Rogers' enhancements into Captain America (comics) proved a continual failure. For instance, the 1950s version of Cpa tried to do with a Nazi copy of the Super Soldier Serum, but those notes made no mention of the necessary Vita-Ray component and the raw chemicals he injected into himself drove him insane.

Fanfic

 * Imperfect Metamorphosis: Marisa utilizes what is apparently a rather excessive amount of magic-boosting concoctions prior to the mass brawl against . She, a Badass Normal in comparison to her comrades in the fight, is the only member to make it out of the whole snafu unscathed, at least by   herself: she's bedridden with intense nausea and hallucinations from the aftereffects later.

Film

 * Mr. Tony Montana of Scarface fame achieved partial-Implacability through the heavy use of cocaine, which also caused his estrangement from his wife and the death of several of his friends.
 * Not a serum, but a surgical technique, is used to ease the agony of burn-victim Darkman, soon after his near-death at the hands of Mafia thugs. Unfortunately, the severing of spinal tracts that carry pain signals to his brain also causes extreme moodiness and bouts of uncontrolled rage.
 * The Reavers in Serenity were the result of an experimental drug pumped into the air on the planet Miranda. The Pax killed most of the population, but some had the opposite reaction, becoming mindlessly aggressive.
 * How did it kill them? Why
 * The film version of The League of Extraordinary Gentlemen reduces Doctor Jekyll's serum to this, leaving out the psychological explanation. One particular moment that breaks some viewers Willing Suspension of Disbelief has an enemy Mook downing a whole bottle of the potion to become a gigantic version of Mr. Hyde...which makes no sense, as all the potion is supposed to do is release your evil side. Drinking a larger amount shouldn't really make a difference.
 * Possibly the normal dosage eliminates a person's good side, but spares the neutral aspects of one's personality along with the evil? An overdose could suppress good and neutral both, meaning that not even basic self-preservation instincts would remain to keep the evil side under control.
 * Bear in mind also that this was Dante drinking it, The Dragon for . Not only was he drinking the attempted replication of the Hyde formula, and a whole lot of it, I imagine that he's got considerably more malevolent natural tendencies than Jekyll. And also remember that while Hyde might be a monster, he has his redeeming moments. Especially since both sides affect the other, it would make sense if they did so passively, too: Jekyll's mind seeps into Hyde's personality, even if his body is weak.
 * The Crazies is based on a psycho serum being released into the local watershed.
 * The Direct-to-DVD Steven Seagal vehicle Attack Force has a villain dumping a drug called CTX into the water supply of Paris to turn them into vampire-like killers.
 * Max Payne, has Valkyr redesigned into a super-soldier serum. While it initially shows promise in granting soldiers increased focus, stamina, and reaction speed, repeated or prolonged use ultimately results in a schizophrenia, delusions, and ultimately, homicidal behavior.
 * Emil Blonsky in The Incredible Hulk. Though in his case, it isn't serum but

Literature

 * The Strange Case of Doctor Jekyll and Mr. Hyde
 * The Spice in Dune is a cornerstone product: it gives a host of benefits like longevity, higher intelligence, and the possibility of Psychic Powers. It is vital to interstellar travel, as Navigators of the Spacing Guild require huge amounts of it constantly in order to perceive the "higher mathematics" needed to safely guide their ships. Drawbacks include addiction, vivid blue eyes, Psychic Dreams for Everyone, risk of death from overdosing or withdrawal, mutation into zero-g floating Fish People (for Guild Navigators) and a crippling galaxy-wide dependence. On the planet Dune, the source of the spice (which must flow), addiction and the blue eyes are the only main problems, though.
 * Imriel gets a surprise dose of this in Kushiel's Mercy. Ironically, being flat out of his head for a month turns out to be the best thing for him, given the situation that he's in.
 * Weirdly subverted in Jonathan Strange and Mr. Norrell where the insanity is not a side effect but the reason he's taking it to give him Power Born of Madness.
 * Andre Norton's Sargasso of Space described "crax seed," apparently chewed like tobacco (there's a reference to someone having spit out a crax cud). While high on it, you're lots faster, stronger, and smarter than normal. When you come down, you come down hard: "What occurred to them later was not pretty at all."
 * In Stephen King's book, Firestarter a government organization called the Shop uses a drug called Lot Six on college students (they tell them that it's a harmless hallucinogenic). Lot Six causes the participants to develop various supernatural powers, such as telekinesis and mind control, but out of the twelve participants, two die right away, two go insane, and five eventually commit suicide because of it.
 * Superchacol was this in the Hawk & Fisher novels.
 * Malazan Book of the Fallen: the "Blood Oil" used by Karsal Orlong's people induces Berserker Rage, blood lust and just plain lust. It says something about Karsa's people that they seem to consider the boost in strength the stuff confers icing on the cake.

Live-Action TV

 * The famous comic book artist/writer Isaac Mendez from Heroes used heroin to access his clairvoyance. He later went clean and learned to use his power sans-drugs.
 * The serum that used on himself probably qualifies, given its less than desirable secondary effects.
 * Despite her initial reluctance to using them, Beka Valentine on Andromeda used Flash, a "stim," to boost her reaction times and become a formidable pilot, but eventually quit it.
 * In The Invisible Man Darien Fawkes, former Gentleman Thief, can turn invisible thanks to a gland implanted in his brain which secretes a substance nicknamed Quicksilver from his pores. If he uses the Quicksilver too much, it builds up in his bloodstream and drives him insane. The show also inverts this trope, as Darien needs regular injections of a Counteragent to * keep* him sane.
 * Season 4 of The 4400 revolves around the mass release of "promicin" injections, which have a 50% chance of giving the recipient paranormal abilities, and a 50% chance of killing them outright.
 * Doctor Who had this in "The Fires of Pompeii". Breathing in the special hot spring vapours would give a person psychic powers, and with time and repetition, turn them into a giant creature made of rock.
 * The Wraith enzyme in Stargate Atlantis confers strength, increased sensory ability and resistance to Wraith weapons at the cost of the user's sanity after a prolonged period of use, and harsher withdrawal symptoms.
 * The armbands SG-1 uses in the episode Upgrades give increased physical and mental abilities, but impaired judgment and reasoning. Also, they could not be removed. I don't recall an addiction, though.
 * The Sarcophagus is very useful for curing illnesses, injuries, and, y'know, death, but can cause severe addiction and nasty withdrawal symptoms, as Daniel Jackson found out in the episode Need.
 * Repeated use steadily causes insanity. It's mentioned that this is probably why the Goa'uld are so unbalanced...and thus why they are Genre Blind Card Carrying Villains to a man (except for the Tok'ra, who don't use the Sarcophagus for this exact reason...Q.E.D.).
 * One episode of Law and Order Special Victims Unit featured several rapes committed by soldiers due to the aggression-enhancing effects of experimental battle-stims disguised as a malaria vaccine.
 * On The Young Ones, Vyvyan creates a potion that turns the drinker into an ax-wielding homicidal maniac. Subverted and lampshaded in that this is, in fact, precisely what Vyvyan had intended it to do.
 * He in fact described it as "a cure for not being an ax-wielding homicidal maniac!"
 * Babylon 5 featured "Dust", which temporarily gives its users uncontrollable telepathic powers which allow them to rip memories from the minds of others.
 * Since the ending implies it was developed by Psi Corps, who were themselves influenced by The Shadows, its psychotic effect was probably deliberate and not just a side effect.
 * The Lost Girl episode "Raging Fae" concerns a human prize fighter whose protein shakes are being secretly spiked with Fae sweat which allows him to Hulk Out. Unbeknownst to him and the Fae spiking his drinks, the enhancement is giving him increasingly frequent rage blackouts and slowly killing him.
 * Half the Buffy the Vampire Slayer episode "Beauty and the Beasts" was based on this trope. A high school kid took Psycho Serum and turned into a big evil monster guy.
 * Sam Winchester of Supernatural spent half the season break between three and four, and all of season four, using demon blood to enhance psychic powers conferred upon him by feeding him demon blood as a baby. This allows him to kill demons without necessarily killing their hosts, a power no one else in the setting except angels ever demonstrates, and angels rarely bother. There turn out to be three definite problems with the system:
 * One, the woman providing him with it is engaged in a long-term manipulation to help the current Big Bad with her
 * Two, most definite an unavoidable problem: The stuff is incredibly addictive, and his growing addict behaviors are not good for any other part of his emotional life.
 * Three, it apparently is, to some degree, slowly turning him into something other than human. To what degree his bad behavior stems from this instead of straightforward addiction is impossible to determine; he never seems to approach outright Transhuman Treachery, and he demonstrated a capacity for being dangerously obsessive before he started on the stuff. A majority of his choices were actually pragmatic logic for the greater good, but they sure as hell wrecked his relationship with his brother, who has this weird power to be right about everything even when it's for the wrong reasons.
 * At any rate, a Sam willing to make sacrifices was a major change in his character, and it was one way or another down to the combination of Poisonous Friend Ruby and Psycho Serum.

Tabletop Games

 * In the Tabletop RPG Rifts, one of the character types is "Juicer". A juicer has a device that continually delivers a cocktail of drugs into his bloodstream, granting him super strength, reflexes, and senses. The catch? It's instantly addictive, and withdrawal can be fatal. If they don't quit, the drugs will kill the user within seven years of starting. Also, he rolls a percentage to see if the drug causes one of several mental disorders.
 * There are also the Crazies, who gain superhuman strength via brain implants, at the cost of sanity.
 * Fungus brew in Warhammer Fantasy gives the goblin chugging it superhuman (OK, supergoblin) strength. It also turns them into a gibbering lunatic who has to be subdued by the rest of his unit sitting on him until the enemy get close enough, at which point said goblin is hurled at the enemy and left to rotate around the field for the rest of the battle, pulverising everything he crashes into with an Epic Flail... until the brew wears off (causing a brief demonstration of a spiral in action), or the goblin crashes into a tree, is pulled down by sheer weight of numbers, or gets shot by the enemy/his own side (depending upon tactical needs). A hero with the Madcap Mushrooms can make this even worse for whoever gets hit.
 * As with everything, Warhammer 40000 doesn't so much run with this trope as shoot it into space. Too many factions to count in the Imperium use versions with the most famous being the Eversor Assassins, who are injected with such a vast and volatile concoction of Psycho Serums that they not only have to be kept unconscious between missions due to being dangerous and deranged even by Imperium standards but explode when killed. Then there are the Chaos and Dark Eldar versions, which are impressive not only for their tendency to be made from human remains but their ability to turn already daemonically-enhanced, Axe Crazy psychopaths more insane and into even more brutal combatants, the Emperor's Children Legion in particular known to have about fifty percent of their bloodstream composed of nothing but combat stims.
 * Don't forget the COCAINE! NANANAAA!!!

Videogames

 * Terran Marines from Starcraft use stimpacks to boost their damage, with the cost of 10 HP (and Terrans Marines only have 40 HP total) with each dose. It is also stated by the Marine webpage on Starcraft2.com it causes long-term effects not limited to insomnia, weight loss, mania/hypomania, seizures, paranoiac hallucinations, internal hemorrhaging, and cerebral deterioration. There is a character within the Starcraft universe who apparently got addicted to stim packs.
 * Slightly subverted in that the same web page mentions that Marines almost never live long enough to see these side effects anyway.
 * In Starcraft II, terrazine gas is a rare variant of vespene gas that stimulates psychic powers, but in its raw form it's highly addictive and lethal -- cutting it with jorium crystals makes for a more stable compound that is used to transform Ghost candidates into the Superpowered Prototype Spectres.
 * Xenogears has "Drive", a stimulant that gives Solaris' soldiers heightened abilities but can cause addiction and violent behavior. For Elly, this manifests in a boost to her ether power but also makes her go berserk until The Power of Love calms her back down. Oddly, neither she nor any of your other party members suffer these side-effects from using Drive as an inventory item, where it merely gives them a permanent stat boost.
 * Even After the End, the Fallout series is chock full of such 'chems' as buffout, mentats, stims, med-x, jet and, yes indeed, psycho! While a range of side-effects from temporary stat penalties to damage occur immediately upon taking them, and a chance of becoming addicted (which will cause further stat penalties if you go without them too long, accumulating repeatedly until withdrawal is completed) exists, there is one exception: It's a-ok to regularly pump yourself full of fistfuls of the completely side-effect free standard size stimpacks every single day.
 * And don't forget the always popular FEV.
 * And with your stims, be careful on the recommended dosage; too much, and while you'll regenerate like a Ghoul in a reactor, you're going to get the side effect of Stim Sickness.
 * Phazon from the Prime trilogy of the Metroid series. It isn't quite clear whether to call it Psycho Serum, radioactive ore, or malevolent fungus.
 * Radioactive Psycho Fungus.
 * The Corruption sounds more fitting.
 * The Super Stem Cell juice Adam in Bioshock allows users to literally rewrite their DNA to give them all manner of superpowers, from fireballs to computer hacking to shooting bees from their hands. Naturally, it quickly becomes a very highly sought-after resource in Rapture, and despite the obvious dependency issues and the tendency of users to become hideous mutants with hooks for hands (an acceptable cost), the struggle for control of it quickly tore the city to pieces.
 * Oddly there is no in-game penalty for using plasmids or tonics when the protagonist uses them. Possibly justified since he is . Either that, or he just hasn't been using them long enough for the side effects to occur.
 * The side effects on the protagonist are hinted at in the good ending:
 * Also evident in the slippery slope leading to the bad ending. Killing more than two little sisters, even if you save all the others causes you to Harvesting gives you more ADAM than saving and if everyone else who used ADAM turned insane, why should you be any different?
 * City of Heroes has a whole pharmacy's selection of these drugs.
 * Overuse of Superadine is what turns people into Trolls in City of Heroes. Side-effects include green skin, hair loss, growing horns, developing super strength, and becoming a big dumb brute.
 * The Council loves this stuff. By level 30, most of their troops have been given dozens of supersoldier serums augmenting everything from strength to height, at what is hinted to be a great cost of free will and intelligence. Nictus Fragments either turn you into a barely sentient warwolf or provide minor dark matter generating powers before an alien awareness takes over your entire nervous system in a fit of unadulterated evil. Shadow Cysts are a planet-wide version of the Psycho Serum concept; they allow Nictus free access and seem linked to the opening of Pandora's Box, which empowers Heroes, but enough of them cause the entire planet to be overwhelmed in darkness and every sentient being to turn into warwolves.
 * Freakshow have a cocktail of different drugs of all types, but Excelsior is the real Psycho Serum of the bunch. Thanks to an experimental Crey military booster drug, Freakshow can regenerate from normally lethal wounds, augment themselves with questionably sanitized cybernetics, and even come back from the dead. Those that weren't already insane before joining the Freakshow are universally driven off the brink by the drug's side effects and nasty withdrawal, and most Freakshow carry around packs of the stuff feeding directly into their veins.
 * The Lost and the Rikti are intentionally exposed to a nasty and powerful mutagen causing extreme physical deformations and psychic powers, at the cost of drastically changing entire modes of thought and eventually hooking the user up into the Rikti psychic network, driving them against normal human society. Oh, and the physical deformations ain't pretty.
 * Arachnos Tarantulas were once human beings, doused in chemicals, and hooked directly into machinery that could not fit a whole human body. The Tarantula Queens are defined as those who came out of the process with two things: amazing psychic powers, and crippling insanity.
 * Except Becky!
 * Hamidon himself picked up a Psycho Serum that turned him from a human-hating man into a human-annihilating giant jello blob of death; he was probably mad to start with, though. His followers, the Devoured, are normal humans who may or may not have liked the Devouring Earth's demands, and turned into freakish monsters with amazing powers but utterly subservient to Hamidon's insanity.
 * The Infected and the Contaminated drank sewer water and Rikti drugs, respectively. Results may include glowing eyes, superhuman resistance to damage, electrical powers, and a desire to bring down society.
 * Krylov's Creations invert the concept; they started out villainous, took the relevant Psycho Serum to gain powers, and either went on a mad killing spree in a villain lab or decided to go play hero... while being slightly insane.
 * The Well of the Furies itself can be a Psycho Serum, as it empowers whomever imbibes it's waters with the powers of a random deity. There are three characters known to have imbibed directly from the Well of The Furies.
 * Marcus Cole: A.K.A. Statesman, who received the powers of Zeus. This granted him Flying Brick powers with a side dose of Shock and Awe.
 * Stephan Richter: A.K.A. Lord Recluse, who gained the power of Tartarus. This caused him sprout spider legs out of his back and become increasingly sensitive to sunlight, though he did get a major strength and intelligence boost.
 * And the most compelling case of all... . The Well of the Furies doesn't seem to have a very good track record so far... And don't even get me started on Tyrant and the Reichsman...
 * Oh yeah, that one other thing...
 * In Final Fantasy VII and its associated works, cells from Jenova (the game's Eldritch Abomination) are frequently used to give the subject enhanced physical abilities (e.g., strength, speed, durability, etc.) as well as unusual powers. But those same alien cells also frequently cause varying degrees of psychological instability and/or gross physical mutations, depending on the amount and the method of infusion, as well as the specific individual involved.
 * Regular SOLDIERs such as Zack are carefully screened and selected for both physical and mental fitness by Shinra. They develop superhuman combat abilities after being subjected to a combination of Mako and Jenova cells, but don't appear to suffer any noticeable side-effects. The only visible abnormality from their transformation is slightly glowing eyes from the Mako infusions.
 * Sephiroth clones, Cloud included, were subjected to Mako and Jenova cell treatments similar to SOLDIERs. However, since they weren't screened for mental stability like normal SOLDIER candidates, Sephiroth Clones generally suffer severe personality breakdowns and become vulnerable to Sephiroth's mental control. They're frequently seen hunched in black robes, muttering disjointed phrases related to Reunion, Jenova, and Sephiroth.
 * Cloud also received enhanced physical abilities from the Sephiroth Clone experiments, which helped make his claim of being an actual SOLDIER believable.
 * Special research prototypes such as Sephiroth, Angeal, and Genesis were subjected to significantly more extreme experiments involving Mako and Jenova cells. On top of the expected enhanced physical abilities, they also develop various special powers (e.g., Angeal's ability to absorb other creatures as well as produce Angeal clones, Genesis's ability to transform others into Genesis Clones, etc.). However, the presence of extreme amounts and/or types of Jenova cells in their bodies probably resulted in all three developing varying degrees of mental instability (e.g., Sephiroth's descent into insanity at Nibelheim, Genesis's obsession with 'the gift of the Goddess', Angeal's suicidal self-loathing, etc.), as well as blatant physical mutations (e.g., Sephiroth's cat-like eyes, their ability to manifest a single wing, Angeal's ability to absorb and fuse with other creatures, etc.)
 * Hojo mutated into various monstrous forms, presumably as a result of injecting or ingesting excessive amounts of his own special Jenova cell-based Psycho Serum.
 * Jenova cells are also responsible for the enhanced combat abilities of many of the Tsviets and Deepground fighters in Dirge of Cerberus, but probably also contributed to the craziness displayed by many of them.
 * How can anyone forget William Birkin from Resident Evil 2 who goes as far to inject himself with his own virus when attacked by a team sent to steal it from him? He massacres them all (except for one, a card-carrying Badass) and goes on to become the game's Big Bad.
 * The nightmare drug Valkyr from the first Max Payne was originally meant to be a Super Serum of sorts for the military, enhancing the stamina and morale of infantry troops. Project Valhalla, which was responsible for creating Valkyr, was canceled after the nasty effects of the drug made themselves known. But the key figure of the project, Nicole Horne, knew exactly what she had in her hands and continued the experiment unauthorized..
 * Valkyr eventually became a common street drug; with a memorable encounter between Max and Jack Lupino, a gangster driven insane by his "V" addiction. The sequence was either full of terror, Narm, or both. Additionally, Max's nightmare sequences in the first game are a result of being dosed with Valkyr.
 * In Jak II Renegade, one of the ways the Baron tried to recapture his prized experiment, Jak, was by warning him that the Dark Eco in his system, though granting him powerful combat abilities, would eventually drive him insane and soon afterwards kill him horribly. Judging by the previous game's Big Bads, he wasn't exaggerating.
 * Red Flowers in Cave Story turn the cute little Mimiga bunnies into giant Killer Rabbits. The kicker? The Big Bad figures out how to use it on himself.
 * Haze revolves around the Psycho Serum Nectar. One faction uses it; the other faction doesn't . You play as both in the course of the single-player or cooperative game.
 * The Dark Nostrum from Suikoden V sends those who take it into an instant Unstoppable Rage with increased power on top of that, but said rage is so extreme that the user loses all rational thought and is reduced to simply screaming at the opponent while going ballistic on them. Oh, and it also kills the user after the effects wear off.
 * In The Elder Scrolls IV: Oblivion, a certain rival guild is discovered to be using Hist Sap, a revered substance in its homeland and a powerful Psycho Serum.
 * The plot of Batman: Arkham Asylum involves a chemical called Titan, derived from Bane's Venom formula.
 * Far Cry revolves around the Mad Scientist Dr Krieger who developed a mutagen that enhances every organ in the body but turned the subjects into ultra violent killing machines - the Trigens.
 * Project Eden has a drug than grants immunity to pain and increased strength, just one side effect
 * The Halo series has what are called Waverly Class Augmentors, also known as Rumble Drugs, that have been used by rebels in their attempts to fight Spartans by overriding the body's natural safety limits. Most died well before even getting near a Spartan but not before doing terrible damage to anything in their way. In the short story/animation "The Heart of Midlothian", an AI directs an ODST who was stabbed with an energy sword to inject himself with one so that it will keep him long alive long enough to destroy the ship which has been boarded by the Covenant.
 * Warcraft have several of these. In the pen-and-paper RPGs optional rules include that all arcane casters are prone to arcane magic addiction which can cause (and not limited to) growing extra limbs (sometimes not functioning limbs as fingers and eyes and even horns), paranoia, spontaneous casting (including self teleport while sleeping) and other mental and physical ills. Addiction to demon magic (Fel Magic) is the same only on the highway and with auto-white/green-glowing-eyes (also turns the user to evil in many cases). More literal serum is drinking demon blood (especially Mannaroth's) which turns the drinker into a fighting addict psychopath with uncontrollable urge to kill anything else that has not turn to CHAOS RACE (but mostly orcs). Comes with glowing red eyes, increased size and strength (enough to kill a god with special damage type to accomplish this) and in more sever cases the skin also change color to dark red (also makes the drinker a total traitor and douchebag as an unpleasant extra).

Web Comics
"Agatha: (still tipsy) I believe another forty-five point three seconds, and I would have exploded or something.
 * You do not under any circumstance eat the Mind Honey. Ever.
 * If you're strong enough to "take" it, the Jägerdraught from Girl Genius grants super-strength and near-immortality, but horribly mutates your body. And if you're not, it may kill you outright or mutate your body even more horribly until you beg for death.
 * And the same probably goes for the battledraught Mamma Gkika gave Gil to save his life (which is labelled "Slightly Better than Death", FYI). At least there isn't any better explanation for Gil's superstrength and other, um, interesting behavior against Dr. Merlot and his clank...
 * It appears both of these are derived from . Heterodynes got either resistance or adaptation--to a degree.


 * ...or something."


 * Additionally, Moveit #11.
 * in Season 2 of TV Tome Adventures.
 * Ink in Bibliography is this for Pages.

Web Originals

 * In the backstory of Ruby Quest,
 * In 1999, Bill Clinton injected himself with a highly unstable experimental growth serum.

Western Animation
"Superboy: I get the flight, the heat vision...but I also get angry. Well, angrier."
 * Recounted in The Powerpuff Girls, Mojo Jojo gave a blatantly multicultural group of kids (including one in a wheelchair) some Chemical X, giving them superpowers. Once hooked, he ordered them to destroy the Girls. Afterwards, their actions were completely excused by noting that Mojo put "something bad" in the Chemical X.
 * As I recall it, the first hit was free.
 * Transformers could take Nucleon (from the heart of a black hole) to become stronger and faster, at the cost of Mode Lock.
 * With the use of biomechanical Psycho Serum, wizened Yoda-look alike Colossus Rhodes from Transformers Animated can turn into a giant.
 * In Transformers Prime the Autobots have created an incomplete, which made , tougher, but also more aggressive.
 * From the original My Little Pony series' second TV special "Escape from Katrina": Witchweed potion. It grants strong magical power (plus a size-boost), but wrecks the true personality of the drinker and is highly addictive. Fortunately, Katrina manages to kick the habit.
 * In Young Justice, the "shields" gave to Superboy suppress his human DNA for one hour. He gets the full range of Kryptonian powers, but since the human DNA was used to stabilize Superboy in the first place, Superboy also becomes far more unhinged and aggressive.

Real Life

 * Truth in Television: At high enough doses, PCP & similar narcotics grant their users near super-human fighting abilities, because they prevent the users from feeling pain or fear, in addition to making them crazy, of course. This also means the druggies have no way of knowing, or caring, how badly they get hurt, which can have some pretty horrific consequences. Don't do drugs, kids!
 * This is referenced on Buffy the Vampire Slayer, where cases of vampires going on a rampage are always written off as "thugs on PCP."
 * This was also used to rationalise away the first Terminator.
 * There was a TruTV police car dashboard-cam video (with audio) of a guy on PCP. The wild mood swings were unnerving enough, but the completely inhuman roaring and growling, plus a voice straight out of The Exorcist (when the user was capable of intelligible speech) was serious Nightmare Fuel.
 * Technically PCP is not a "narcotic" (that classification includes codeine, morphine and their related compounds); it's a dissociative anesthetic, originally marketed as such for surgical use. At sufficiently high doses--which, apparently, isn't much (unlike ketamine, which has similar effects but in a less horrifying manner, usually)--the user completely loses all physical sensation. Think of it as the ultimate Out of Body Experience. (Whereas with narcotics you still realize there's pain, but it doesn't bother you.) Evidently the human mind can't cope with The Void, so it tends to "fill in the blank" with what appear to be surreal alternate realities, or...?
 * Above info for the purpose of clarification only. Just because they lie about some drugs, don't assume all drugs are relatively harmless. Some of them truly have the ability to mess up your head, permanently.
 * In the trial for the LAPD officers who beat Rodney King near to death, the officers attempted to justify their actions by claiming that they were afraid that Mr. King was high on PCP and going berserk when he resisted arrest. Turns out that he was actually just really, really drunk, mildly stoned, and just plain tough enough to throw off multiple officers attempting to wrestle him down and to shrug off two taser shocks before the brutal beating commenced.
 * There's also certain prescription medicines that in already mentally ill (though not psychotic) individuals caused homicidal ideation.
 * Ephinephrin was used heavily by many insurgents on the Second Battle of Fallujah for this exact purpose; while under the effects of these drugs, their bodies would keep functioning (brains, muscles, and heart activity would continue) even after being injured to the point that they would die from shock, making them sort of like zombie terrorists.
 * One theory on the source of Viking Berserkers' Unstoppable Rage is that they ate large helpings of psychoactive mushrooms before battle.
 * While the more potent varieties tend to prefer more tropical climates, several varieties of psychoactive mushrooms do indeed grow in the cold climatic regions inhabited by the Vikings.
 * Not to mention that Fly agaric is even named "Berserkjasveppur" (Berserker mushroom) in Icelandic.
 * Anabolic Steroids are also known to lead to increased aggression in many users, a phenomenon colourfully known as "Roid Rage". Though you really shouldn't mention "the R word" on any body building forum.
 * Those Wacky Nazis used meth in large quantities, under names as "tanker's chocolate" (in quantities of over 17 million pills per month during the Battle of France). Many of the German flying aces were (sometimes constantly) on meth, and it's widely assumed that the Luftwaffe wouldn't have been able to support the blitzkrieg offensives if their pilots weren't able to fly 12 hours straight thanks to meth. It did lead to... some side effects after the war. Hitler himself also became increasingly addicted to the stuff up until his death at the end of the war after it was initially prescribed to him for his constant health problems.