[[quoteright:330:[[Film/IronMan2 http://static.tvtropes.org/pmwiki/pub/images/IronManPaladiumPoisoning1_6237.jpg]]]]
[[caption-width-right:330:[[WhatCouldPossiblyGoWrong Who'd have thought]] [[EmergencyTransformation putting]] an experimental clean energy source in your chest might have [[PowerDegeneration harmful]] [[HeroicRROD side effects]]?]]

->''"He has veins on his forehead now, which is the official ''Franchise/StarTrek'' code for "This poor bastard is in for a horribly painful transformation and/or death." Seriously, if you are ever yourself in a ''Star Trek'' episode and you see this happening to yourself'', [[SuicideIsPainless turn your phaser on yourself]]. ''There is no hope if you have a veiny head unless you are [[RubberForeheadAlien an alien]] or [[PlotArmor a main cast member]]. Just put yourself out of your own misery."''
-->-- '''{{Website/SFDebris}}''' recaps ''Series/{{Star Trek Voyager}}'s'' "Threshold"

''[-[[WaxingLyrical Sometimes I feel I've got to (dum dum) run away I've got to (dum dum) get away from the pain that you drive into the heart of me]]-]... ''

In general, the tendency of people suffering some sort of abnormal condition to develop highly visible, off-color veins all over their body or near the distressed areas.

Might be due to catching a bite from someone/thing infected with TheVirus, or as a manifestation of a villain's RedRightHand after willingly succumbing to TheDarkSide or TheCorruption. It's also possible if the character is suffering a SuperPowerMeltdown, PowerDegeneration, or as a side effect to taking too much PsychoSerum. A [[OurVampiresAreDifferent vampire]], [[OurWerewolvesAreDifferent werewolf]] or other supernatural critter hit with DepletedPhlebotinumShells inducing a burning reaction (or even just partial sun exposure/blood starvation) may develop Tainted Veins because their [[GlamourFailure glamour is failing]]. Special mention goes to [[ZombieApocalypse zombie bites]] for always creating nasty necrotic veins wherever they bit.

Expect characters with a HealingFactor (or with friends possessing HealingHands and or a MagicAntidote) to quickly and neatly reverse the appearance of these veins.

See also VolcanicVeins for when they '''[[color:orange:glow]]'''. Compare VeinOVision, which is where a character has a power that makes them see the world this way.

This is a JustifiedTrope (TropesAreNotBad): There are toxins that cause venous thrombosis (clotting of blood in veins) which can make surface veins visible and dark - especially if the clotting is in deep tissue in an affected limb. For sake of {{squick}} control on the main page, RealLife examples should go in the Real Life [[RealLife/TaintedVeins section.]]

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!!Examples:

[[foldercontrol]]

[[folder:Anime & Manga]]
* Babidi's human henchmen in ''DragonballZ'' have unusually bulging veins without discoloration.
* This is one of the warning signs of Tetsuo's imminent mutation near the end of ''Manga/{{Akira}}''.
* Greed in ''Manga/FullmetalAlchemist'' gets these whenever he and [[spoiler:Ling]] have a disagreement.
** [[spoiler: Ed]] also gets these temporarily when [[spoiler: Pride tries to [[GrandTheftMe take him over]].]]
* [[http://static.tvtropes.org/pmwiki/pub/images/Yami_Marik_8267.jpg Dark Marik]] of ''Anime/YuGiOh''.
* Inverted in ''Manga/{{Bleach}}'', where highly visible veins are caused by the use of "[[GratuitousGerman Blut Vene]]", a [[spoiler:Quincy]] [[SuperToughness defensive technique]].
* Kurumu from Manga/GakkouGurashi gains these on her right arm, the right side of her neck, and a bit of the right side of her face, after her close brush with [[spoiler:zombification]]. It is unsure if this will be permanent however.
* These have a tendency to show up whenever someone's using their powers in Manga/SnowWhiteAndSevenDwarfs. With it being a series about being BlessedWithSuck, they're generally not a good sign.
[[/folder]]

[[folder:Film]]
* The vampires in ''Film/ThirtyDaysOfNight''.
* ''Literature/{{Dreamcatcher}}'' had this, but it was an alien plant growing into the infectee's face.
* The vampires in ''Film/InterviewWithTheVampire'' had visible veins on their faces, too, but that was as much due to their creepily transparent porcelain white skin as it was to their veins being full of freshly drunk blood.
* Tony Stark's Palladium poisoning in ''Film/IronMan2'' displayed these symptoms.
* alien-influenced humans in ''Film/{{Skyline}}''.
* Poison Ivy's toxic kisses cause these to appear on her victims in ''Film/BatmanAndRobin''.
* This happens to whoever Rogue touches in the ''{{Film/X-Men}}'' movies.
** Mutated Senator Kelly also has them before he dies.
* ''{{Demoni}}.''
* A sign that you are falling under the BigBad's sway in ''[[FiveGirls 5ive Girls]]''.
* Zombies in ''RockabillyZombieWeekend'', as part of the gradual breakdown of their body, have their veins gradually begin bulging out until they're visible as thick purple lines etched across their bodies.
* In ''Film/StarTrekFirstContact'', as the Borg invade the Enterprise, they convert crew members by injecting (presumably) some kind of nanobot version of TheVirus which can be seen spreading through dark veins from the point of injection.
[[/folder]]

[[folder:Literature]]
* From the ''Literature/DresdenFiles'' novel, ''Changes'', we are treated to a minor case of this courtesy of Ebenezar.
* In the ''Literature/SkulduggeryPleasant'' series, [[spoiler: people possessed by Remnants (evil shadows/sprits) get black veins and lips, but only if the Remnant wants to show itself. Otherwise they just look like normal people.]]
* When Tash Arranda is infected with TheVirus in ''Literature/GalaxyOfFear: The Planet Plague'', she starts off with a rash that becomes a swelling bump with raised brownish veins. [[spoiler: Then it starts [[BodyHorror leaking]] brownish-green BlobMonster goo.]]
** Spore assimilates people by sending out dark vinelike things that sink into the skin and are quickly only visible as a "dark tracing of lines", like veins.
[[/folder]]

[[folder:Live Action TV]]
* Dark Willow on ''Series/{{Buffy|The Vampire Slayer}}''.
* An episode of ''Series/StarTrekTheNextGeneration'' had Geordi get infected by a disease that covered him with [[VolcanicVeins invisible blue glowing]] veins. ItMakesSenseInContext.
** Borg assimilation does this, with added blueish-grey skin.
** SFDebris notes that if your veins start going weird (and especially on your forehead), you're screwed unless you're a main character.
* The [[Series/DoctorWho 2nd Doctor]] was up against a "plague" that gave a moonbase crew tainted veins. Eight years later, the same tainted veins gave the 4th Doctor a clue who he was up against.
** In the series 5 two-parter ''The Hungry Earth''/''Cold Blood'', [[spoiler:Alaya poisons Tony]]. His veins turn green.
* In ''Series/{{Smallville}}'', Clark gets 'em when [[KryptoniteFactor Kryptonite]] is around... and KryptoniteIsEverywhere.
* Happens a few times in ''Series/{{Supernatural}}'', more notably when [[spoiler:Castiel is possessed by the leviathans.]]
* Skinner in ''Series/TheXFiles'' episode "SR 819" was poisoned by {{Nanomachines}}. He got better. However, it was never fully resolved and he could be affected by it later at any time.
* In ''Series/{{Wolfblood}}'' when a character is close to transforming into a wolf they get these along with SupernaturalGoldEyes.
* This is the main symptom of the plague spread by Pestilence in the ''Series/SleepyHollow'' episode "John Doe".
* In ''Series/{{Helix}},'' victims of TheVirus develop black veins, particularly visible in the denuded infected lab rats the CDC researchers use for testing.
* In ''TheVampireDiaries'', this is a standard part of a vampire's GameFace. The veins around their eyes appear to writhe with a black taint.
* People affected by Alisha's power in ''Series/{{Misfits}}'' have their veins turn blue until contact is broken.
[[/folder]]

[[folder:TabletopGames]]
* The Seventh Soul in ''{{GURPS}} Villains'' has black veins all over its body. These are its only persistent identifying feature, since it reincarnates.
[[/folder]]

[[folder:Video Games]]
* After [[spoiler:Beatrice]] dies in ''VideoGame/DantesInferno,'' her spirit form has dark veins... [[FanDisservice all over her naked pale chest]].
* In ''VideoGame/DeusEx'' and other games set in the same universe, nanotech augmentation gives you this. Although you're [[SuperSoldier far from sick...]] [[spoiler: Actually, you ''are'' sick and your augs and Gray Death are one and the same, you are just immune to the bad symptoms]].
* In ''VideoGame/DragonAgeII,'' this is one symptom of the Darkspawn corruption that finally kills [[spoiler: Wesley]].
** [[spoiler:And Bethany/Carver, if she dies in the Deep Roads.]] Or anyone who dies via the Taint, of course.
* In ''VideoGame/{{Killzone}},'' Helghast have these, as a result of the first settlers trying to adjust to Helghan's sickly atmosphere and hundreds of years worth of forced evolution.
* In ''VideoGame/KnightsOfTheOldRepublic'', ash-pale skin with blue veins signifies your character going completely darkside.
* Happens to Leon in ''VideoGame/ResidentEvil4'', during a [[AllJustADream dream sequence]] after he's infected with the ''Las Plagas'' parasite. Fortunately for him, he's able to find a cure before anything like that starts to happen for real.
* In ''VideoGame/MetroidPrime 3: Corruption'', each time Samus absorbs a Phazon Core, her veins become more noticable; bigger, longer, bluer.
* ''VideoGame/{{Spore}}'' has this as a variant of coloration for your creature.
* Taken UpToEleven in ''VideoGame/{{Prototype}}'' and ''VideoGame/{{Prototype 2}}''. Alex Mercer's and James Heller's bodies are covered in thick, pulsating red and black veins when they unleash their Blacklight-virus powers.
* In ''VideoGame/FarCry'', seeing the veins in your arms turn dark is how you find out that you've been exposed to the mutagen.
* ''VideoGame/{{Skullgirls}}''' Painwheel has dark veins all over her body, thanks to the experiments that transformed her into her current state.
[[/folder]]

[[folder:{{Webcomics}}]]
* In ''Webcomic/WakeTheSleepers'', [[http://wakethesleepers.com/comics/53 Locke's hand]].
[[/folder]]

[[folder:WebOriginal]]
* In the ''GlobalGuardiansPBEMUniverse'', when the supervillain Virus injects his victims with the mind-control serum, their veins turn dark green around the injection site.
** Cyborg supervillain La Constructeuse has this sort of thing going on with her own body, but the vein-tracery looks like circuitry.
[[/folder]]

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