A character is either dying or badly injured when they start bleeding from the mouth.
In Real Life, coughing blood can indeed indicate life-threatening damage. It can result from organ and tissue damage from disease or trauma; punctures in the respiratory and gastro-intestinal tracts; and massive trauma to the body as a whole. This is an especially big warning if the lungs have been punctured, as the victim can drown in their own blood if not treated. As a death trope it's caused by any fatal injury, and is less a symptom than a signal to the audience that this dude's a goner. Much like the chest-clutching and doubling over in days of old, Blood From the Mouth is a sign of death that won't horrify us with the specifics, keeping our focus on the story itself.
However, not all Real Life bloody mouths are immediately dangerous. Damage to the gums in a fistfight, biting your tongue, or a particularly copious nosebleed can just as easily replicate the appearance. When it's not a death trope, blood around the mouth simply indicates the character has just taken a worse beating than usual. Our hero gets smacked around some and ends up with a bloody lip - not a big deal unless there's staggering involved. They might even spit out the blood defiantly, along with a tooth, just to showcase their resolve. Was that hit fatal? If the character wipes the blood away and it does not return, it's cosmetic Blood From the Mouth. Expect to hear My Name Is Inigo Montoya any second now.
A subtrope of He's Dead, Jim.
See also: First Blood, Soap Opera Disease and Incurable Cough of Death. Saying I'm Cold... So Cold... is another very bad sign. Occasionally overlaps with Deadly Nosebleed.
Not generally related to the Psychic Nosebleed; combine the two and get Blood from Every Orifice. If it's the only sign the character gives that they're injured, it's a Mortal Wound Reveal. Blood from the mouth is also an increasingly popular way to show damage taken from a Deadly Upgrade, or over reliance on a Super Mode.
A stream of blood trickling from the mouth is also shorthand for "I am a vampire."
As a Death Trope, all spoilers will be unmarked ahead. Beware.
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Anime and Manga
Happens a lot in Shonen series that focus on combat. Used to show that a character really has lost a battle.
The Hyūga families fighting style uses chakra to inflict internal injuries rather than external ones. You only know you have been hit after you cough up blood.
When Naruto fights Sasuke in an effort to stop him from defecting to Orochimaru, the first hit Sasuke gives him is a Megaton Punch that causes this in addition to sending him flying.
We later see it happen to Itachi during his final fight with Sasuke. No, he hadn't been hit by a Hyūga, he just had tuberculosis or something the entire time. And he still kicked ass.
Also happened to Kimimaro who had a fatal disease.
Jiraiya has quite a bit of blood coming from his mouth when he dies, as a result of his throat being crushed. Hinata, while appearing to be dead in the eyes of many viewers, had a trickle of blood coming from her mouth. Pain coughs up blood after using Chibaku Tensei, having already used up most of his chakra.
In one of the more recent chapters Naruto is bleeding from his mouth after a brutal beat-up from a Cloud ninja.
Who can forget Part 1's Big Finale, after which Sasuke coughs up blood near Naruto, who is passed out on the ground? (It was a rough fight.)
Danzo starts drooling the red stuff after getting squeezed by Sasuke's Susano'o. But it's apparently not fatal nearly as what happens at the end of the chapter (He's okay). He starts again (for real) after taking a fatal hit and Karin does as well (she lives though).
Tsunade has Blood From the Mouth in her battle with Orochimaru after she jumps out in front of his Kusanagi sword to protect Naruto. Subverted, though, in that she gets up and continues to fight (and even heals herself).
He somehow does it through a face-concealing mask in his later fight with Grimmjow.
Censorship in the anime (which is incredibly inconsistent about whether real blood can be shown) gets a bit silly with this. When Uryu's stomach is destroyed by Szayel Aporro, blood pours out of his mouth; in the anime, WATER comes out instead.
Yu-Gi-Oh!: Happens a few times in the final story arc. Whenever one of their monsters are destroyed, many of the characters cough up a small amount of blood, often shortly before dying. The most extreme example would be Bakura (or at least one of the numerous versions of him), who, upon losing a duel against Yuugi, coughs up a huge glob of blood, not long before dying.
The ancient Bakura actually vomits blood before dying. He comes back.
Yu-Gi-Oh! GX: In an episode explaining Daitokuji-sensei's, or rather, Amnael's, origins, he coughs up a little bit of blood due to succumbing to a terminal disease, but he makes a second body right before his first one dies.
Fai spits out blood when he fails to transport himself and Kurogane out of the collapsing world of Celes. Pretty much expected when half his power has been diminished after C!Syaoran ate his left eye.
Also happens to Kurogane's mother earlier on.
Played with in Pandora Hearts: Break sometimes does this after a battle, but it doesn't mean he's lost; in fact, it's a pretty good sign that he just stomped someone into the ground with Mad Hatter. It's just that using Hatter puts such a strain on his body that he'll probably be dead in a year.
Hyatt from Excel♥Saga does this constantly. She also has the tendency to die, sometimes from this; in the final episode, she bleeds so much from her mouth that the world floods.
Pretty much every time a character in Dragon Ball Z got a nice hit in the gut, they'd fall to their knees and start hacking up blood. They are usually fine a few seconds later, strangely enough. It makes more sense in the dub, where the blood is edited out so that it seems like they are coughing just because the wind got knocked out of them.
This happens so frequently that when a DBZ character hacks up blood, it's treated with about the same concern as if they just had the nonlethal, busted-lip variety. One notable instance was in the first Broly movie; blood is dripping down Broly's face, and he stares at his opponent... then abruptly smiles and licks it off, getting a fairly entertaining Squick reaction from Goku.
In the original version, Trunks gets one after getting a hole blown through his chest by Perfect Cell.
When Krillin is impaled by Frieza, he throws up a damn river's worth. This one was justifiable, though, as that hit would have killed him if not for Dende.
Which Frieza licked off of his face too.
When Frieza charges Goku at one point during their battle, Goku punches him right in his chest, causing him to vomit a big gob of blood, as a reminder of Goku's new-found Super Sayian power.
In the movie Bojack Unbound, this happens to Bojack when Super Sayian 2 Gohan punches a hole straight through his stomach. In this case it's, if not a mortal wound (Future Trunks doing the same to one of his minions killed them instantly), then a severe one that likely would've killed him if he weren't so powerful.
This usually starts happening to people near the end of a season of Slayers.
Just about every time someone dies in Samurai7, they do it half-choking on blood.
Although toned down in the anime, by a lot, in the manga, you can't help but feel sorry for Tsuna when he gets punched around or nearly suffocated to death by the Big Bad. All this beat down results in a lot of that unpleasant red stuff. Good thing the manga portrays it as black.
Resident Ill Girl Chrome suffers from this whenever her illusionary organs give out. Immensely freakier in the manga where they actually show her coughing up quite a bit of blood.
While fighting Envy in Gluttony's stomach, Ling gets punched and flung into a stone pillar with enough force that he coughs up a small gob of blood.
During his Last Stand battle with Scar, King Bradley briefly stops to cough up a puddle of blood. Justified in this case, as it's established he's already mortally wounded and wants to go out fighting.
Homunculi are capable of healing any wound by relying on the power of the red stones they've consumed, so the first real step in defeating them is often to perform an alchemical ritual which causes them to vomit up all of their red stones.
Greed vomits up red stones and blood.
Also happens to Edward in the last episode, when he is stabbed in the chest by Envy.
In the movie, rivers of blood ooze from Wrath's mouth after he is bitten by Gluttony, and he spews even more when Gluttony nearly chomps him in half. Also, Alfons Heidrich develops a life-threatening illness that causes him to cough up blood from time to time.
Subverted in Metal Armor Dragonar, in which a somewhat minor Humongous Mecha pilot is shown coughing up blood constantly within the two episodes he is in. However, getting blown up when his giant robot is destroyed is what finally does him in.
Since the demons of Chrono Crusade have the ability to regenerate, this trope is often used to show when someone's given them a serious blow. It's rarely used for humans, however—the only time is when Mary Magdalene is given a fatal blow by Aion in the manga.
Negi gets some blood from the mouth after being impaled by a giant stone spear shortly after returning to the Magic World. He also heavily pukes blood after getting the complete crap beaten out of him by Rakan in the final match of the tournament. Both times, these are caused by obviously major damage. Both times, he gets up anyway.
It happens in a flashback too, when the Mage of the Beginning obliterates Ala Rubra in one hit, most of them have Blood From the Mouth.
Happens to Graham Aker every time his Mid-Season Upgrade (he's had a fairly absurd number of them) surpasses his body's tolerance. The explanation seems to be that the G-forces are messing with his internals. He lives, though.
Also happens to Sergei Smirnov, after his son "fatally wounds" his mobile suit. He is killed in the ensuing explosion.
Happens again with Nena Trinity before she dies, although her blood is a result of the Regnant's Fang destroying almost her entire abdomen. She uses the little energy she had left to let Louise know EXACTLY how she feels about her for doing that.
In Zombie Loan, Michiru exhibits this in the second episode. Although it's not as much of an indicator as the massive pool of blood around her after she took a sword strike for another character. She got better.
Though it's more a sign of grief than death, it happens in Slayers Evolution R (episode 10) to Zelgadis when he learns Rezo can't cure him. Oh the poor, poor dear...
Though to be fair, Rezo was likely screwing with him. Having the source of ultimate evil sealed in your soul and all that, maybe he just lied to keep Shabranigdo in check.
The trope is played straight during the more brutal battles, though. The most noteworthy case is from the same season above when Zelgadis is nearly crushed by the resurrected Rezo-Shabranigdo, causing him to cough up a notable dose of blood.
Luffy coughs up blood more than once in his fight with Rob Lucci. It's subverted when Luffy not only keeps going after coughing up blood, but stands right back up.
Usopp pretends to be coughing up blood from previous injuries while fighting Luffy, but uses it to make Luffy hesitate.
Played straight with Usopp by the end of the episode.
Played for Laughs by Sanji when he is forced to admit his poorly-drawn Wanted Poster is indeed him by Ivankov.
Dr. Hiriluk in Chopper's flashback does this to show that he's dying of an incurable disease.
In the manga of Elfen Lied, this occurs to Lucy repeatedly as she overuses her enormously powerful vectors, causing her body to deteriorate from the effort. Eventually, she is reduced to nothing more than a puddle of flesh, bones, and organs.
Happens to Haruhi while taking story suggestions from the SOS Brigade for their new amateur film. She has to be hospitalized at the end of the sequence.
In Saiunkoku Monogatari, Sa Sakujun bleeds copiously enough from the mouth to soak the front of his clothing, even though rather than suffering any internal injuries he is succumbing to a poison he'd taken much earlier in the day. Transferred to Shuurei's lips afterwards.
In Fushigi Yuugi, the first sign that Nuriko is a goner in his battle with Ashitare is when he coughs up blood, bleeding much from his lips among other places afterwards.
This seems to happen to Allen Walker in nearly every battle of D.Gray-Man, though it doesn't so much indicate his death as just him being beaten the crap out of by bad guys. He usually returns the favor.
In the first episode, Van is knocked aside by the dragon and rolls a little ways. He then vomits well over a quart of blood. Which is odd, since he survives so much damage during the series that he's clearly some sort of robot.
There's also a later time where Van begins coughing up blood, seemingly unprovoked, while the heroes are imprisoned by Zaibach. Rather than a rapid onset of Tuberculosis, it turns out to be because the bad guys have started dismantling the mech he's permanently synched to. Heart first.
Happens rather graphically◊ to Miroku in InuYasha whilst trying to suck Naraku into his Air-Rip. He not only bleeds from the mouth but from the nose, ears and eyes.
This is shown to be a symptom of the virus in the manga Bloody Monday, as well as that of those suffering from neutron radiation.
Happens at least twice in Kara no Kyoukai, when Fujino was dying due to her appendicitis, and when Araya was impaled by Shiki.
A Certain Magical Index: Index, in bit of a creepy moment when she's in her 'self defense' personality, is going through the magical requirement to heal her slashed internal organs - and hello proper reason to actually have such bleeding. She's trying to get Komoe to perform magic when she pauses to cough up blood and then instantly continues in her former robotic manner.
Towards the end of the first season, after November 11 has killed his treacherous boss, he's seen staggering down the street, trying to get call someone on his cell phone. He stops and coughs up blood, and smiles sadly—then the camera angle changes to show that he's been shot in the stomach and there's blood all over his suit. Blood From the Mouth was the least of his worries.
Also happens to Havoc earlier in the season when November 11 kills her.
Rave Master abuses this one. In a sword fighting manga blood from the mouth is more common than cuts.
This happens occasionally. Notable examples include when Death The Kid realized he'd had part of his hair cut (making it asymmetrical), Maka after the fight with Free on London Bridge, where the blood was black, indicating she was affected by... black blood and Mifune after being defeated by Black Star for the third time. In the anime he lives, in the manga he does not.
Karate Shoukoushi Kohinata Minoru: During their fight Kevin squeezes Minoru's throat hard enough to make him cough up blood and drinks the blood.
Subverted constantly in Berserk. Whenever Guts takes a massive blow from an enemy, especially if it slams him into the wall or floor, blood pours vigorously from his mouth, and he certainly appears dead most of these occasions. But he never dies.
Black Butler II: Alois does this at the end of the 7th episode after being stabbed by Ciel.
In Emerging, blood running from the mouth and eyes is a good sign that the unknown disease ravaging Tokyo is entering its final stage. This generally precedes blood gushing from the mouth, nose, eyes, and every other orifice.
In Beyblade, blood drips from Kai's mouth when he is battling Brooklyn.
Haku in Spirited Away was bleeding a consistent amount after being inflicted by a curse and Yubaba didn't even try to help him, saying he would die eventually. It is Justified since he had originally swallowed Zeniba's golden seal. And of course, he is healed by Chihiro.
Liang Qi in Canaan, as a side effect of failing to give herself Synesthesia.
Almost everyone in Claymore has had blood spurt from their mouths at some point or another. It's usually justified by the character having just taken a sword or clawed hand straight through the gut. The blood itself usually isn't indicative of impending death on its own, as they can heal massive amounts of damage.
In Future GPX Cyber Formula, this is how Hayato's father, Hiroyuki dies when he coughs up blood from his mouth after being seriously injured in a car accident (in which said car exploded and the debris stabbed him), and the accident was set up by Smith.
Tsukune from Rosario + Vampire coughs up a decent quantity after getting his shoulder crushed via an enraged half-breed monstrel.
In the conclusion of Rebuild of Evangelion 2.0, the Tenth Angel impales Unit-01, causing Shinji to vomit up a torrent of High-Pressure Blood due to his high synchronization rate. This is the first hint that things are going to happen, since it shows that Shinji retains an absurdly high synchronization with his Evangelion despite the fact that Unit-01 was impaled after the power ran out. Now angry, he reactivates the Unit, and an impressive resurgence against the Angel occurs.
In the Strike Witches movie, Yoshika gets this while she's being pursued by the giant tower Neuroi. She gets a much worse injury at the end of the fight, though.
In a non-serious example, England from Axis Powers Hetalia coughs up blood whenever the Fourth of July comes up or anything relating to independence is mentioned.
A Cruel God Reigns: Ian coughs/throws up quite a bit of blood after a long stint of stress over his relationship with Jeremy and Jeremy's emotional state.
In Macross Plus, we see this just before Guld crashes his fighter into the unmanned drone; he coughs out a giant gob of blood as the G-forces crush his internal organs.
Happens to Abe Sapien in a Hellboy issue, who spits up quite a bit of blood after being impaled through the chest by a spear; understandable in this case, since the spear most likely punctured a lung. He gets better, though.
When Marv is in the electric chair in the Sin City story, "The Hard Goodbye", the first jolt fails to kill him, but it makes him spit up a mess of blood (though in the movie it may not be blood, since his blood was always shown as a bright red while the goo was black. Considering he's a smoker, he might have been chewing on the stub of a cigarette; which darkens ones' spit.)
This trope is evoked with the Red Lanterns. Becoming one involves a person's blood being replaced by a burning red acid which they can use as a weapon by puking it at opponents.
When Superman-Prime captures Mr. Mxyzptlk and tortures the hell out of him, at one point he vomits blood. Prime comments on how disgusting it is.
Jhonen Vasquez once made fun of this trope in his deliberately horrible comic, The Bad Art Collection. A character is wounded and blood comes from the mouth. Paraphrased: "Oh, no! I did a blood burp! That means I'm dying!"
During the fight between Zeus and the Incredible Hulk, Zeus punches the Hulk in the stomach and he vomits up a mass of green blood.
In Legion of Monsters: Morbius the Living Vampire, a girl spews up a geyser of blood as she's turning into a vampire.
In The Punisher v7 #13 a mook is shot with a type of bullet that opens up to reveal the crab-like construction inside, which then digs its way through the victim's body. Said victim ends up spraying a 2-feet-high fountain of blood from the mouth. He still manages to get up and run.
Inverted in Morbius v2 #2. Morbius coughs up blood just as the wound from a shotgun blast to the chest heals and gets back up.
Very prominent in I Did Not Want To Die, where the protagonist is first shot in the stomache, and realizes that he's been mortally wounded once he starts coughing up blood.
Happens to Mercutio in this Romeo and Juliet fanfic.
A less serious variety happens in thisDigimon Adventure fanfic in chapter 4. Tai gets kicked in the face during a major soccer match and notices something's wrong when he spits out blood. He's forced to leave the game because of it.
In the "Tamers Forever Series", Takato's deteriorating health is shown from him coughing up blood several times during Silent Sorrow. During his torture by the Kurasarimon, the author showed he was Not Pulling His Punches by using this (more so even than Takato's screams of agony).
Happens to both Patchouli Knowledge (though she was just badly injured) and Koakuma in the Touhou fanfic "Scarlet in Black's" first part.
How Kevin knows that Ben's not doing well after the fight with Fusion Buttercup in "Pipeline".
Done in the Fantastic Four. When the bad guy starts discovering his powers, he shoots someone straight through the chest with some kind of electric shock. The injury nowhere near the mouth, but the guy has a stream of blood tickling down his mouth before he collapses, obviously dead.
The lead characters in The Sting have blood coming out of their mouths after a shooting at a racehorse betting counter. The blood, however, and the entire shooting were all staged, and the characters are perfectly fine and comfortably richer, too.
In Lawn Dogs, a man who quite frankly deserves it, is later seen bleeding from the mouth after getting shot in the back by Devon, the 10 year old heroine, who is trying to protect her friend Trent.
In The Bucket List, Edward confirms he has cancer when he coughs up blood into a handkerchief.
In Blade Runner, blood flows from Deckard's mouth into a backlit shot glass. Possibly the most beautiful Blood From the Mouth scene ever shot- but honestly, do you expect anything less from Ridley Scott?
After being impaled by Shelob in Lord of the Rings, Frodo starts frothing from the mouth before collapsing.
Boromir has blood from the mouth when he gets shot by multiple arrows.
Masterfully done in Return of The King. Shots of Faramir leading a suicide mission are inter-cut with Denethor casually, and messily eating food. You see Orcs shoot a massive amount of arrows at the men of Gondor... and cut to red juice dribbling down Denethor's chin.
Naturally shows up a few times, given all the people getting beat across the mouth. Tyler makes particularly disgusting use of the effect to intimidate a guy. Also turned on its head in the case a bullet-hole in the cheek - does the blood still count if it's not actually come out of the "mouth"?
Inverted (literally) with the Narrator's line, "You can swallow a pint of blood before you get sick."
In Moon Child, Sho spits up blood when he is shot by Son. From the position of the bullethole and difficult breathing, the bullet might have punctured his lung.
'Jaws'': As Quint gets munched on, blood dribbles from between his clenched teeth and down his chin.
The opening scene from the Drivers' ed film Mechanized Death features a woman coughing up blood after an accident. Serious nightmare fuel.
In The Woman in Black, a girl who drank lye suffers from a severe amount of of oral bleeding immediately before dying.
Used to show how badass a secondary character in The Last Samurai was. In the middle of the climactic battle Ujio is shot in the stomach by a soldier whom he kills after an appropriate stagger. Several other samurai come to help Ujio but he unceremoniously pushes them away, spits out a bright red spray of blood and goes on fighting. It takes the Gatling guns to finally finish him off.
In the Bollywood film Rang de Basanti, Aslam coughs up blood after he gets beaten up by the police at a demonstration. He gets better.
Nicole Kidman's character has this as a symptom of her dying in Moulin Rouge!. Justified since she's dying of tuberculosis and bloody mucus is one of the symptoms.
In the film Silver Streak, Ned Beatty's character is shot and dies talking to Gene Wilder with blood coming from his mouth.
In Wong-Kar Wai's last movie The Grandmaster, Gong Er, played by Zhang Ziyi, spits blood on her white scarf.
In Wild at Heart, the girl they find at the roadside, victim of some car crash. Totally unjustified, but a clear signal of Lynch's playing with tropes, and most probably the most chilling instance of "Wicked Game" as background music, ever.
In Predator, the titular alien hunter coughs up blood (bright green, glowing blood, but still blood) as he activates his doomsday self-destruct device.
In Jane Campion's Bright Star, Fanny finds out that Keats is ill when she sees blood-stained linen (he's not seen coughing blood at that point, but the implications are pretty clear.)
In Das Boot the lethal version of this happens to the Captain. In the novel, it is explained that he has shrapnel wounds through his back.
Happens frequently in slasher films, eg in Scream 2 when Phil is stabbed in the head.
In The Doctor, William Hurt's title character coughs up blood while leaving a party. This turns out to be the first sign that he has cancer.
In the movie Kiss Kiss Bang Bang Perry is shot in the chest. Harry gives him a couple of breaths (he probably "learned" CPR from the movies), then pulls away and a stream of blood flows from the corner of Perry's mouth. He got better, though.
Socko from Freaked. Despite being a mutant with a sock puppet covering a human hand for a head, he somehow manages to bleed from his 'mouth' as he lies dying from gunshot wounds.
In Batman Begins, the old man referred to as Ra's al Ghul was bleeding from the mouth after being hit by a pile of logs in a burning building Bruce Wayne and Ra's al Ghul were both in.
The father from The Road coughs through most of the movie, but his fate becomes absolutely apparent when he coughs out a large amount of blood near the end.
Found in Red Tails Lighting coughs up blood before his death.
Played straight then subverted in the Korean film Thirst, where a priest volunteers for an almost certainly fatal experiment. As the disease spreads throughout his body, he coughs a huge amount of blood over (and through) the pipe that he had been playing. He dies shortly thereafter, but makes a miraculous recovery. Later on, he experiences a sudden resurgence and coughs blood again, but this time doesn't die...well, nottechnically.
In the Undisputed films, particularly the sequels, a shot of blood spewing from someone's mouth as he takes a huge shot to the chin, usually accompanied by the mouthguard flying out, seems to be an almost universal symbol that the fight is done, and the bleeder has lost. It rarely goes more than 30 seconds from that point.
In Herschell Gordon Lewis' The Gore Gore Girls, a woman is chewing bubble gum, and is blowing a bubble, when she's bashed over the head with a mallet, and the inside of her bubble is sprayed with blood.
In Stahlnetz: PSI, a German crime movie, a small girl is kidnapped for ransom and at some point hit in the face by one of the kidnappers. This is not directly presented as dangerous, but this signifies the danger of her situation.
In Heroic Trio almost every fight scene involves one or more fighters spitting up blood. The climax is definitely a repeat offender.
In Vertical Limit, two characters suffer from pulmonary edema (water forms inside the lungs) after getting trapped inside an icy cave. They cough up blood as a result.
In Lara Croft: Tomb Raider: The Cradle of Life, the establishing character moment for the bioterrorist/scientist villain Jonathan Reiss is him in a private jet with his clients. He poisons one who snitched on him to Interpol, intoning "this is the sound of a traitor dying" as he gurgles his last, bleeding profusely from his mouth.
In Cabin Fever 2, the attendees of a school prom have been drinking punch that a) was made from bottled water from the small town featured in the first Cabin Fever movie—you know, the stuff that's infected with necrotizing fasciitis—and b) was thereafter pissed in by a custodian infected with the same disease. About halfway through everyone starts vomiting blood all over the place as they apparently realize that their internal organs have liquefied.
In Three Extremes a female character bleeds from the mouth right after she killed the offspring in her womb.
In Apache Gold, Klekih-petra, an old man who is a white father to the Indians dies with the ominous blood, being murdered by Santer. He doesn't die immediately and begs Winnetou, a future Apache chief, to save the peace.
In Fruitvale Station, Oscar Grant sports this after being shot. Sure enough, the doctors reveal that he has been hit in the lung and that the damage is so severe that it had to be removed. This proves to be futile, as they are unable to stop his internal bleeding and he eventually dies.
In Higher Learning, a gunshot victim spits up blood. Sure enough, she rapidly dies.
One of the more squicky parts of the werewolf transformation in The Wolfman (2010). What? You think those pointy teeth just poof into your mouth?! Might also possibly be from internal organs shifting around and what not...
This is very common in Chinese literature, where characters are described as expelling blood through the mouth due to not only injuries or disease but also anger, sorrow, and annoyance.
After repeatedly being thwarted by the genius strategist Zhuge Liang in Romance of the Three Kingdoms, Zhou Yu expires from coughing up blood in rage.
A few chapters before her demise, the heroine of A Dream of Red Mansions, Lin Tai-yu, does this after learning an unfortunate secret.
In Dan Abnett's Gaunt's Ghosts novel Ghostmaker, when the Ghosts run across a particularly bad patch of Chaos, they start bleeding at the mouth.
Also used straight in the same novel, when a wounded trooper dies while Gaunt is calling for a medic.
In Sabbat Martyr, while Kolea is lugging Mkvenner to the Saint, Mkvenner's coughs splatter blood. Justified because he suffed from severe internal damage.
And Rawne coughs up some when a Chaos sorcerer is trying to control him.
In Dan Abnett's Warhammer 40,000 novel Brothers of the Snake, the seriousness of Inquisitor Mabuse's injuries shown by having him bleed at the mouth, though he lives long enough to provide the Marines with evidence that they were working for him.
In Harry Potter and the Half-Blood Prince, Harry is described as wiping a trickle of blood from Dumbledore's mouth after the latter is hit with a Killing Curse and blasted off the Astronomy Tower.
Older Than They Think! In Act V, Scene 2 of Shakespeare'sHenry VI, Part 3, as Warwick dies he complains that he cannot speak clearly for all the blood and sticky stuff erupting from his mouth.
Even older than that. The Song of Roland has the titular character blow a horn so hard he gives himself an aneurysm. A stream of blood flies out through the horn, and his brains start leaking from his ears. Roland wanders around a bit more, pays his respects to his fallen, climbs a hill, tries to destroy his sword, fails and destroys a very large rock instead, kills one more stray bad guy by bashing him with the horn, and symbolically faces the land yet to be conquered before the cranial hemorrhaging and displaced brains catch up with him.
A strange subversion happened in a Doctor WhoEighth Doctor Adventures novel: Fitz smokes thirty a day, so it's no real surprise when he suddenly starts coughing up blood for no reason in particular. The weird thing is that it's never brought up again and whatever was the matter with him apparently clears itself up between books.
Played with in Darkness Visible - when putting his brain under extreme stress, Lewis bleeds from the nose and the eyes, but not actually from the mouth. The sense of this being a Bad Thing remains the same.
Hawkfrost coughs up clots of blood shortly before he dies at the end of Sunset.
Tigerstar at the end of the Rise of Scourge manga.
Non-fatal example: At one point in Forest of Secrets, Graystripe has blood bubbling from his mouth.
After he is hit by a car, blood trickles out of Whitethroat's mouth as he tries to speak.
In Moonrise a doomed Tribe cat has blood coming out of its mouth after being slammed against a wall.
Snowfur, when she's hit by a car.
In the short story "The Clans Decide", blood comes out of an injured she-cat's mouth as she tries to speak. She gets better, but she is near death at this point.
Phase, in "Ayla and the Grinch", in the Whateley Universe. After she tries to stop a demon who wants to force its way into their world, she's so badly injured she's bleeding from her mouth, nose, and eye. And elsewhere. Lots of elsewhere. It turns out she was dying from her injuries, but she gets saved in the nick of time by a mutant healer.
Spider, near the end of Anansi Boys by Neil Gaiman, justified in that his tongue had been ripped out by the Lady Of Birds.
The Spencer Dunmore novel Bomb Run is about the crew of an RAF Lancaster in WWII. One of the gunners is injured by flak and when the others attempt to contact him he tries to speak 'but his mouth was full of blood.'
In There Is a Happy Land by Keith Waterhouse, the unidentified narrator finds Marian's body in this condition. It's implied that she had an extremely brutal and horrifying death, but the very young narrator doesn't realise this.
This is one effect of the fictional disease Chimera in the novel Gravity by Tess Garritsen.
A dead man in A Brother's Price is found to have blood clotted in his nose and mouth. His tongue was cut out, but someone botched it and he either bled to death or choked on his own blood.
In the novel Gone with the Wind, Scarlett is relieved when the injured Ashley does not have this, because she frequently saw this while she was a nurse during the Civil War and came to know it as a harbinger of death.
In Dave Barry Slept Here, the Five Token Bands who fought World War II in movies "would learn, despite their differing backgrounds, how to trickle syrup from the corners of their mouths to indicate that they had been wounded. In the actual war, of course, real blood was used."
In The Hunger Games, President Snow's mouth is constantly bleeding as a side effect of the numerous poisons he's had to ingest while inducing the poisoning of political rivals (antidotes having only been able to do so much). It tends not to seep out, but it smells so strongly that he constantly wears genetically modified roses in order to cover it up.
Live Action TV
In Three Kingdoms, this is the main indicator of illness, severe injury, poisoning, shock, and every other ailment that results in a character collapsing or dying shortly afterward.
Derek, after getting claw-stabbed in the back by an Alpha Peter Hale.
Scott, after being shot by Kate.
Parodied in the Spaced episode "Combat". Mike takes a paintball for Tim, and starts coughing up paint. Probably not for the first time; before the game starts, Tim is lecturing Mike not to take things too seriously and get himself banned again. One of the things he tells him is "not to eat the paintballs".
When Clayton and Simpson duel to death, at first the villainous Simpson collapses and Clayton appears uninjured, but then a trickle of blood comes from his mouth and it turns out he's been fatally shot.
Lt. Eccleston in "The Even Chance". It's a variation of this trope since the bleeding doesn't seem to be internal but he was either hurt in his mouth or his lips were badly cut. However, visually, it's definitely Blood from the Mouth.
Another instance of Kill the Cutie from "Retribution": Mr Midshipman Wellard dies a heroic death, facing death with dignity. Before that, he kills some of their Spanish enemies, but is shot and Blood from the Mouth indicates that he is not going to make it. He manages to confess a possibly important secret to Gunner Hobbs.
Jack Hammond, a rather hopeless Midshipman, is shot at the end of "Loyalty", just as he was proving himself brave and worthy. Some blood comes out of his mouth, he has a heart-wrenching dialogue with his uncle, his courage is commended, and that's the end for Jack Hammond.
Providing proof that being a Jamie Bamber fangirl means a hard, hard life, Law & Order: UK sent off Matt Devlin in nearly the exact same manner as his character Archie Kennedy from Hornblower (right down to the Heroic Sacrifice). The last seen of him on screen in "Deal", he's bleeding from the mouth (and elsewhere); in the beginning of the next episode, "Survivor's Guilt", he is mentioned to have died of his wounds.
This is used literally almost every episode in Supernatural. Except, oddly enough, both Dean and Sam's first death scenes.
In the LOST season 5 finale, this happens to both Jacob and Juliet.
And in Season 6 this is what prompts Richard to get some real help for his wife. Instead of saving his wife, he ends up accidentally killing the doctor, Isabella still dies and things go From Bad to Worse from there on.
Considering all the deaths in Torchwood, this happens a surprising once. To Owen.
Subverted in Breaking Bad. At first it seems to demonstrate that Walter's lung cancer is getting worse which convinces him that he needs to step up his meth production to make enough money for his family after he's gone. However, it turns out later that his cancer is actually in remission and the blood he was coughing up was the result of an (easily treatable) tear in his esophagus.
In House of course, the list of people who don't spew blood is shorter than the list of people who do.
Angel: This is the first sign that something is wrong with Fred in "A Hole In The World". In the middle of an incredibly sweet scene in what has been until now a mostly light-hearted episode, she starts coughing up blood, sending Lorne and Wesley into panic mode, and giving the audience a severe case of Mood Whiplash. She dies at the end of the episode.
On NCIS, when Tony contracted pneumonic plague, one of the signs that things were going downhill was when he started coughing up blood.
At the beginning of Season 15, one of the first signs that something is seriously wrong with Greg is when he starts spitting up blood.
Another, earlier episode had Carter going to someone's house trying to track down a patient. He almost tripped trying to back away from a woman who was coughing up blood (she had TB, he didn't want to get it).
Happens to Clark Kent when Doomsday socks him in the gut repeatedly, although he bounces back and wins. From the Smallville Season 8 finale.
Variation from The Sopranos: When Christopher starts coughing up blood, Tony decides it's safe to kill him.
In the eight season of Deadliest Catch, Captain Phil Harris, found himself coughing blood after getting a cracked rib in a nasty storm. It turns out to be from a blood clot in the lung.
In The Event, blood from the mouth, eyes, and nose was the first sign that the passengers of flight 514 had been infected with some unknown agent by their Human Alien captors.
Fatal Attractions had a woman gotten bitten by one of her pet snakes and had her throwing up blood everywhere since snake venom makes you bleed more.
The dying Shingo Izumi has blood pouring from his mouth - though he's resurrected via a Puppeteer Parasite shortly afterwards.
Later, Akira Date spits up blood after being injured by the Greeed, but he survives and is far less badly wounded than Shingo was.
In Kamen Rider Gaim, Kota bleeds from the mouth during his first battle with the Byakko Inves.
In the last episode of Choujin Sentai Jetman, Radiguet's otherwise-unstoppable One-Winged Angel form is impaled through a weak spot on its back, and blood starts pouring from the mouth of the human face that's still there on his torso. Ya don't see that in Power Rangers..
Chris's death in the second series of the British Skins.
From an episode of Forensic Files, where a teenager has killed his father note Only the 911 transcript was shown, so it's possible the body was right next to the door:
The first season of the Australian drama Underbelly is ridiculously fond of this trope. Greg Workman, Alfonse Gangitano, Nick The Russian, Mark Moran, Dino Dibra, Paul 'PK' Kallipolitis and Carl Williams all get shot and end up with blood pouring from their mouths. Carl is the only one who survives, but to be fair he's the only one who receives a single bullet wound.
Played hilariously Up to Eleven and Crosses the Line Twice in It's Always Sunny In Philadelphia in an episode where Charlie is masquerading as a cowboy with tuberculosis. In order to sell the disguise, he swallows "Like a million of those little blood capsules", hoping to cough up blood and impress the girl he's with. However, he gets sick and proceeds to VOMIT (fake) BLOOD all over her. Bonus points for trying to pass it off as "A touch of consumption".
In Criminal Minds, when Reid contracted Anthrax he began coughing up blood when he took a turn for the worse.
In Chinese Paladin, Ling'er bleeds from the mouth after her Heroic Sacrifice. Unlike most examples, there is a lot of blood involved, and it gets very messy very quickly.
In The Walking Dead, When Rick is forced to kill Shane, you can see the blood as one of them apologizes.
During the second season of Ice Road Truckers, Alex Debogorski begins to suffer from shortness of breath and cough up blood. The cause turns out to be a blood clot in his lung, and he is forced to go home because his doctor worries that he may give himself a heart attack if he keeps driving.
In the Wallander episode "Firewall", this is how you tell that Ella's not going to make it. Indeed she seems to have been shot in the gut. Averted in "The Man who Smiled", although it would have been fatal without Wallander's prompt intervention.
In The City Hunter, Young-ju is left drooling blood after a fatal No-Holds-Barred Beatdown. In this case, however, the blood from the mouth is clearly from superficial wounds, and the least of his problems.
Like the Real Life example with Ronald Reagan below, the Secret Service doesn't notice that Jed Bartlet had been shot until he started spitting up blood.
Rome. Atia orders the slave girl who's bringing her soup to sing for her, but everyone is puzzled when she starts bleeding from the mouth while doing so. Until she drops dead, having sampled the soup on the way to her mistress, who's just escaped a poisoning attempt.
In the Masters Of Horror episode "Imprint", the disfigured prostitute tells how her father eventually coughed up blood after a prolongued illness and promptly died in a river.
In the 2nd season premiere episode of The West Wing, the Secret Service doesn't know that President Bartlet has been shot until he begins spitting up blood as he talks (much like the Ronald Reagan example in the Real Life section below).
In Call the Midwife, Dr Turner and the nurses don't realize that there's a TB epidemic starting in Poplar until one patient at the maternity clinic begins coughing up blood during her appointment.
The Malcolm in the Middle episode "Malcolm Holds His Tongue" has Malcolm keep his opinions to himself for once, but the stupidity of the basketball team proves too much for him to handle, and he suffers a peptic ulcer, throwing up blood on the coach's shirt.
In the video for Trio's "Da Da Da", a waitress is stabbed in the back and reappears in a nearby TV set bleeding from the mouth while singing the chorus. Bordering on terrifying.
Cripple Billy in Martin McDonagh's The Cripple of Inishmaan. (See also Bury Your Disabled.) Justified, in that a large part of the plot revolves around whether or not he has TB.
In Freuds Last Session, Sigmund Freud coughs up blood a couple of times- he is suffering from oral cancer and has to wear an ill-fitting prosthesis after part of his jaw was removed.
Spec Ops: The Line: If Walker is killed by the squad sent to save him from Dubai, he will cough up blood as he lays on the ground dying.
In Breath of Fire: Dragon Quarter, after Ryu and Bosch have ended their battle in their D-Dive dragon forms. Bosch, realizing he is defeated and can no longer control his D-Link willingly allows Ryu to finish him off by means of a claw into his chest. As Ryu holds Bosch in the air, Bosch hacks a flurry of blood into Ryu's face and his body goes limp.
Ryu has a very simillar experience long before that - blood from a mouth and a nightmare face, as Bosch stabbed him before he went "Oh Crap" as Ryu started to transform.
The first Mega Man X game has Zero with blood/mech fluid/oil/some red substance running from the corner of his mouth after sacrificing himself to destroy Vile's Ride Armor. Notably, he does not bleed from anywhere else despite having been torn in half.
In Prince of Persia: The Sands of Time, in the first few cutscenes the Vizier is shown coughing violently, getting blood in his handkerchief. Since he wasn't in a fight beforehand and this has nothing to do with his later death - either of them - it may fall under Vader Breath.
Actually, this particular case of Blood From the Mouth is death related. Specifically, the Vizier knew he was dying, which was part of his motivation for finding the Sands, and thus immortality. I'm sure the whole ultimate-god-like-power thing also had something to do with it, though.
In the Sega CD game Snatcher, the Benson that turns out not to be a snatcher begins to bleed from the mouth as he says his final words to Gillian. The blood is a modest drip; which is strange considering his injuries are so devastating, that Metal Gear Mk. II can't even get the words out.
In the JoJo's Bizarre Adventure Fighting Game by Capcom, if you finish off your opponent with a Super Move, you are treated to a Manga style (complete with black and white shading) close up of your opponent's face, generally with blood coming out the mouth, very satisfying to see, too!
In Final Fantasy Tactics there are several characters who die with blood from the mouth. Duke Larg and Duke Goltana both die coughing a burst of red pixels, and in his final character portrait, Islude is also portrayed as bleeding from the mouth.
Happens fairly often in Trauma Team. This is the result of the hemorrhagic fever caused by the Rosalia virus. True to the trope, this typically means whoever is vomiting blood is nearly dead. Also tends to coincide with Tears of Blood for the same reason.
Averted in Resident Evil 4. Leon and Ashley cough blood throughout the game, but it's hardly a spoiler that neither of them die.
This is all over the place in Vagrant Story. Sydney sports a few pixels of it in the very beginning, courtesy of a crossbow bolt to the lung, and then again toward the end, after Guildenstern has had his way with him. Hardin gets a bad case after Guildenstern (again) stabs him. Neither of the former two take; the latter, however, eventually does.
Crisis Core: Zack bled all over the place, including from his mouth.
Mass Effect 3: This happens a lot over the course of the game. Mordin / Padok if you betray them during the Tuchanka mission, Kirrahe if he's shot by Kai Leng, Kai Leng himself after his boss fight. Finally, this happens to Shepard after surviving a Thanix blast from Harbinger on the way to the Citadel. This is the first time the player has seen Shepard bleed, much less from the mouth, so you know he/she is badly hurt.
Paige from Brothers in Arms Earned in Blood succumbs to this after he is wounded after an attack that vaporizes his squad leader. However, he manages to gather just enough strength to pull Hartsock to safety before dying.
Duck from The Walking Dead begins to cough up blood when he's on the verge of death after being bitten by a walker.
Tsukihime: When Akiha does this near the end of Hisui's trueending, that's how you know that she's about to die.
Unsurprisingly, Okita Souji in Hakuōki inevitably starts coughing up blood as his tuberculosis sets in. In his final bad ending, he takes a sword to the chest and bleeds from the mouth (in addition to bleeding copiously from the actual wound) as he dies.
Ever17 features a (usually) fatal disease called Tief Blau, the primary symptom of which seems to be coughing up and sneezing blood. Until you choke to death on it, usually clawing your throat out at the same time.
In the webcomic Gnoph, Abbey is constantly coughing up blood as a side-effect of the symbiote living in her lung. It's actually referred to by its medical name, hemoptysis.
In Girl Genius, Doctor Vg after a Mercy Kill, as a revenant interprets a vague command as a direct order to activate a deadly weapon, and wishes to spare his friend the coming horror.
In Hanna Is Not a Boy's Name, Hanna throws up quite a bit of blood pretty early on in the story. Subverted in that he doesn't die / isn't apparently dying and is pretty fine afterwards.
Homestuck features fiveinstances so far. Later on, during [S] Cascade, Sollux would start bleeding from the mouth from the stress of psychically moving the trolls' asteroid to the green sun. In this case, the blood from the mouth was just part of the damage, as a lot of the veins on his face were bursting at the same time.
And a sixth time, though in this case, it's more a matter of getting conked on the head and spitting out teeth than any kind of serious injury.
Gamzee spends roughly the entirety of Act Six Intermission Four gushing blood from his mouth after being shot.
Fairly common so far in Shadownova, despite the comic still being fairly new. So far it seems to be justified in most cases. Karen is impaled on a pointy bit of metal and while Carver and Scruffy both only seem to have light external injuries when you consider that the both crawled out of the wreckage of a destroyed building damage from shockwaves and hits from falling debris isn't really a stretch. In Cam's case it's made obvious it's just a split lip.
Seen a few times in Dominic Deegan: Oracle for Hire. In one of the more memorable instances, Szark's infernal wound acts up and causes him to yark blood in his parents' living room. It's the last thing Dominic needs. It's non-fatal, though, and he even apologizes for the carpet he ruined.
In Mitadake Saga, Koji spits up blood after being stabbed.
Page 627 of Haru-Sari has June throwing up a LOT of blood.
In UC, after a group of bullies beat the living daylights out of Nicodemus, he begins to cough up blood. It’s just a result of his broken nose bleeding into his lungs, and he most certainly does not need to go to the hospital, thank you very much, Kelsi.
In Clockwork Game, William Schlumberger has Black Vomit, in which someone pukes up partially digested blood. It's the final stage of Yellow Fever.
Nuzlocke Comics and spinoffs thereof frequently use this to indicate that a Pokemon has been fatally injured.
This happens twice in Broken Saints: the first time to Charles, Bravado, and their men when Shandala gives them a good old Emotion Bomb mind blast; the second time to Raimi in the Grand Finale.
A YouTube video which purports to be a real execution shows a man in the electric chair who starts bleeding from the mouth when the first jolt hits him. Several comments on the video note that the "execution" was, in fact, staged as part of a TV documentary on prison life.
In the YouTube phenomenon "Blood", a toddler accidentally hits his infant brother in the face while playing, splitting his lip and causing him to bleed. The toddler becomes extremely distressed upon seeing his brother bleeding, and tries to tell his dad that there's blood on his brother's face. Hilarity Ensues.
In part 2 of the Synchronicity series from Vocaloid, Rin is shown bleeding from her mouth as a sign that being a Dragon Diva is slowly eating away her life force.
The DCAU was pretty loose with this - one gets the impression that Batman must have had internal organs with incredible regenerative properties, given how many times he's had blood running from his mouth and not died. More reasonable to assume it's a split lip, or accidentally biting his tongue or cheek hard enough to draw blood when he gets hit, especially since they seem to come more often after blows to the face. His mouth is the only visible part of his body. This was even Lampshaded at one time in a comic where after fighting Clayface, an unmasked Bruce showed he had received a black eye from their confrontation, (as well as several other bruises around his chest and torso); something that his Expressive Mask covered up.
In the intro, Him spits out a bunch of teeth and a little blood from a kick in the face from Bubbles, though it could be coming from his nose.
In an episode of Metalocalypse, Nathan vomits blood after seeing the others vomit. It turns out he has a bad liver, getting it replaced later on. This prompts Toki to make a note that "Blood Puke" is a good name for a song before remembering they already wrote it.
In The Simpsons episode "Brother from the Same Planet" during Homer and Tom's fight near the end blood is dripping from Homer's mouth before he is knocked onto a fire hydrant.
In The Boondocks during fight scenes characters will often cough or spit out blood.
In Transformers Prime Cliffjumper bled Energon from the mouth, shortly before Starscream ripped him open.
In Transformers: The Movie, Prowl starts bleeding smoke from his mouth just before he collapses dead.
The British Museum in London has a series of bas relief of lion hunts from ancient Assyria. They are incredibly clear and beautiful, and several of the dying lions show this trope. Since these date to about 650BC, they make the trope Older Than Feudalism.
Attila the Hun actually died this way. It's unknown exactly why he died but he was found drowning in his own blood.
Truth in Television for anyone who's done high school wrestling, in which it's common for wrestlers to be wearing metal braces, and one of the principal moves is the cross-face, which is basically a jab across your opponent's mouth. There are mouth pieces designed to prevent this, but most eschew them because it makes it harder to breathe. Most teams have, during a match, at least one person on duty just to clean up blood from the mat.
When President Ronald Reagan was shot in 1981, the Secret Service agents whisking him away didn't immediately know he had been hit—until he started spitting up blood, whereupon the limo was diverted to the hospital. Reagan survived a bullet wound in his lung.
When Archduke Franz Ferdinand was shot by Gavrilo Princip at Sarajevo in 1914, the fatal bullet entered the Archduke's neck under his tunic collar, severing his jugular vein and badly damaging his trachea (windpipe) before lodging in his spine. This caused blood to spray out forcefully from his mouth, striking one of his staff officers in the cheek. His wife, Duchess Sophie, saw that and cried out, "For heaven's sake, what's happened to you", before collapsing to the floor of the automobile, the victim of a bullet in the abdomen which caused her death within minutes from massive internal bleeding.
Several serious lung conditions, including pleural effusion (fluid in the lung cavity) and pneumothorax (air between the lung and the chest wall, collapsing the lung) present with pinkish-red, frothy sputum as a critical sign. When a patient actually bleeds from the mouth, it's usually from ruptured esophageal varices (swollen, fragile blood vessels in the esophagus) in the context of liver failure. Neither situation is anything to laugh off, as you can't breathe with a collapsed lung, and you can lose a major portion of your blood volume from bleeding varices very quickly.
Blood from the mouth, mixed with mucus, is a symptom of tuberculosis.
During rioting following the 2009 Iranian election, a woman named Neda Soltan received a bullet wound in the chest and died. A cell phone camera video taken of her immediately after being shot received major international attention. The video clearly shows her bleeding from the mouth and nose. And not the little dribble of blood normally used in the trope either. There was a lot of bleeding from the mouth involved.
Mughal Emperor Shah Jahan I invoked this to avoid an assassination/usurpation attempt by his stepmother Empress Nur Jahan. He faked an illness over a period of about three weeks while various officials of the court visited him. On the morning of day one of the closest to his stepmother visited, he allegedly drank three goblets of goats blood, then vomited it up while the official was with him, faking his death well enough to fool the doctors attending him.
In real life, if blood comes from the stomach, it's a brown color, and can be mistaken as a large amount of coffee grounds, bearing no resemblance to "common" human blood. This is one of the common signs of an ulcer in the stomach.
This often happens to people who tend to get bad nosebleeds. Blood trickles into the throat, and the person spits it out. Also happens to some people who get bad nose-colds that TURN into nosebleeds, due to dehydration, a chapped nose, or other causes.
When the battleship Prince of Wales was hit during her duel with the Bismarck, the staff in the combat centre beneath the bridge found blood dripping from the voice-pipes. It was Captain Lynch, the only survivor on the bridge, and he got better.
A blow to the Adam's apple (aka, that lump on the center of a man's neck) can likely cause internal bleeding and forces the victim to cough out blood. It can be fatal if done with sufficient enough force.
As shown in Untold Stories Of The ER this happens to trauma patients. One patient was violently coughing blood and they could not figure out how. Turns out he had accidentally inhaled a push pin that had fallen from a poster his tenant had put up. And the coughing was causing it to shred more of his lung.