Fantastic Medicinal Bodily Product

"Dragon liver can cure a cold, dragon powder grows hair, with dragon blood you'll never grow old.
Dragon cartilage keeps you thin, dragon fat is for burns, a dragon tear will clear up your skin."

— Pete's Dragon (1977), "Every Little Piece"

A creature, or an entire species, possesses remarkable healing abilities due to a particular bodily product. Usually the product is a fluid, likely saliva or blood. In various media, for example, vampire saliva is a natural coagulant and helps the puncture wounds close (incidentally making it a handy tool for maintaining the Masquerade). However, it could be any other bodily product, such as urine or bone. The medicinal properties of the product can also range from healing wounds to curing illnesses to bestowing invincibility. Very often, the healing factor only works on other species, not their own, though this is not a strict requirement for the trope.

Psionic powers used to heal or take away pain do not count under this; they are examples of the Empathic Healer.

Sub-Trope of Bizarre Alien Biology. May be a Panacea.

Compare Swiss-Army Tears and Healing Hands for other body products/parts that heal. If someone tries to profit from these healing body parts through captive monsters, see Monster Organ Trafficking. If the product in question is a waste product or a secretion, see Solid Gold Poop. If the product is repugnant, such as snot or pee, it could be used in a Revolting Rescue. See also Crafted from Animals.

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Examples:

Anime & Manga

• 3×3 Eyes: Invoked by the vampire-like Chui, who seems to firmly believe that drinking the blood of Pai, the last Sanzhiyan (Triclop) will make him immortal. However, it's implied by Parvati that this is a mere rumor and not an actual fact.
• Black Bird (2006):
  • Kyo, a bird demon, licks Misao to heal her wounds.
  • Misao's blood can heal demons, which can be sexually transmitted as well.
• Bleach: Nel's saliva/drool is capable of healing people from near death.
• Blue Ramun: The blood of members of the Blue Ramun tribe can cure nearly all diseases, neutralize most poisons, and accelerate the healing of wounds. The healing powers inherent in the Blue People are explicitly stated to be one of the most potent magical forces in the entirety of the low-magic setting — which is why the Garicalege traffics in stolen blood of the Blue Ramun tribe, and why Dr. Zai murdered his fellow Blue tribe members and attempted to craft medicine from their hearts.
• Mahou Sensei Negima!: in the Magical World, there's a species of demi-humans who have horns that can channel large amounts of magic power. Unfortunately, these horns can also be cut off and used to produce a Panacea. While it is illegal to use their horns like this, that doesn't stop the black market from hunting them.
• Miss Kobayashi's Dragon Maid: Tohru claims that dragon saliva has healing properties (on top of being able to wash delicate clothing), but Ilulu says that she's just looking for an excuse to lick Kobayashi.
• Neon Genesis Evangelion: The LCL that sustains life within the entry plug (that is described as being identical to amniotic fluid) is the bodily fluid of Lilith, the being that spawned all of humanity.
• One Piece: In one arc, the main antagonist is after a rare and old Millenium Dragon, whose bones are said to grant immortality to those who consume them. Later on in the arc, his right hand man betrays him to go after the bones himself.
• Samurai Deeper Kyo: Demon Eyes Kyou at one point uses his own blood to bring a dying Kyoshiro back to life just out of spite. May also count as a case of New Powers as the Plot Demands.
• trash.: The blood of Hiroshi gives those treated with it a Healing Factor but sends people who use it too much into a berserker state in which they can no longer tell friend from foe, which happens to Soo-in and ultimately Francesca herself.

Audio Plays

• Big Finish Doctor Who: In The Bride of Peladon, the Doctor uses his own blood as an antidote, because he'd been attacked and injured badly enough to activate his souped-up Time Lord immune system, releasing special platelets to heal his injuries instead of having to regenerate, effectively turning his blood (temporarily) into a panacea.

Comic Books

• Brat Pack: True-Man's blood is capable of curing HIV and bestowing a healing factor.
• In one issue of the Futurama comic book, Fry's cold infects the citizens of New New York, and once a person gets better they cough up a gelatinous mass that comes together to create a giant Blob Monster. Leela becomes afflicted too, but after her illness goes away, which included stripping naked and living with a pack of squirrels for a few days, she shows off a giant white blood cell on a leash, and Professor Farnsworth deduces that her mutated immune system is what created the large white cell, and they go to the sewers to infect the mutants. When they spit out their giant white cells, the two blobs meet, and destroy each other, saving the city.
• Judge Dredd has a peaceful and harmless intelligent alien race called Stookies — who just happen to have glands in their bodies that make humans appear younger when they eat them. Since the glands can only be harvested by killing the Stookie, this is desperately unethical and immoral, even by Dredd's Crapsack World standards. However, due to Fantastic Racism, it's only a ten-year sentence instead of fifteen to life for murder as alien lives are worth less than humans'.
• Marvel Universe:
  • The Incredible Hulk: In an issue from the early 1990s, Jim Wilson, a former teen sidekick of the Hulk, asks him for a transfusion because he's dying of AIDS and thinks that the Hulk's irradiated blood makes him immune to HIV and will cure him. Hulk refuses, worrying that a blood transfusion might also turn Jim into a gamma mutate, much like it made Bruce Banner's cousin Jennifer into the She-Hulk.
  • X-Force (Milligan & Allred): At one point the team is deployed to Central America to kidnap a boy whose mutant powers make him a living pharmacy. Mr. Sensitive revolts against the team's financial backers after learning that they intended to harvest the kid's organs and bodily fluids to make new drugs.
• Monstress: The Cumean witch-nuns can use the body of Arcanics to create a substance called Illium. It has many healing effects, and even brings a character back from the dead.

Comic Strips

• Bloom County: In one arc, Oliver makes a nearly-magical hair tonic out of cat sweat. It makes balding men grow their hair back overnight.

Fan Works

• Infinity Train: Boiling Point: Witches that are heavily attuned to Healing magic have this in the form of their blood, as explained by Cat.
• Lysenne takes the healing saliva of the vampires of The Saga of Darren Shan and expands on it, like it does with most of that series' vampire worldbuilding. Luca Balsa, the vampire "mad" scientist, has experimented with it and analyzed some of what it does and how.
• Songs of the Spheres: Besides the standard healing body parts available to The Multiverse — your unicorn horns, your dragon livers, your phoenix down — eventually Corona Shimmer comes up with a solution involving her own blood. It bestows immortality.
• A Thing of Vikings takes the How to Train Your Dragon example and runs with it; many of the dragons produce substances (mostly venoms, but some tears and saliva) of medicinal value, including anesthetics, heart medications, paralytics, sterilizing agents, and even abortifacients.

Film — Animated

• Ponyo on the Cliff by the Sea: Ponyo heals Sousuke's wound by licking it.

Films — Live-Action

• Alice in Wonderland (2010): The Bandersnatch's saliva is one of the few things that can heal the wounds left by its poison claws.
• Edge of Tomorrow If the alien's blood gets on you while you're dying it will bring you back to life and send you back in time.
• Naked Lunch: William Lee trades a typewriter to a rival author with the following comment: "Tom, I've brought you a new typewriter (actually an alien head) which conveniently dispenses two types of intoxicating fluids when it likes what you've written."
• Pete's Dragon (1977): According to Dr. Terminus, dragon body parts have a variety of medical uses — for instance, dragon livers can cure the common cold, dragon fat cures burns, and dragon blood halts aging.

Literature

• Adventures of a Demon-Hunting Soccer Mom: Ground saints' bones can reverse death.
• Artemis Fowl: Dwarf saliva is apparently a healing balm, at least against burns.
• Dreamsnake has the snakes used by healers, who have been genetically modified to have medicine for venom. Snake can even feed them certain compounds to create different kinds of medicine.
• Dune: The Spice, which is a product of the life cycle of the sandworms of Arrakis and is the most valuable substance in the Known Universe because it can greatly extend human lifespan, provide enhanced mental and physical abilities and even enable the power to see through time and space. Its value is even greater because of prohibitions on artificial intelligence in this setting, which requires that human potential be maximized.
• Guts and Sass: The Lridrisy, a species of giant shapeshifting cats, have blood with potent healing properties.
• Harry Potter:
  • Phoenix tears can cure any wound they are applied to.
  • Unicorn blood is able to heal people even halfway from death, but due to the atrocity of shedding the blood of something so innocent, anyone who drinks from it is cursed with a half-life from then on.
  • Fantastic Beasts and Where to Find Them elaborates on certain body products.
    • Re'em blood gives the drinker Super-Strength for a short amount of time.
    • Salamander blood is mentioned to have rejuvenating properties, and is thus often used in strengthening potions.
    • Pickled murtlap tentacles can be eaten to improve resistance to jinxes, or made into a salve to soothe painful cuts and abrasions.
• Illegal Aliens: There is a species of sapient trees whose leaves, seeds, and other body parts have remarkable healing properties when used as medicine by any other race in the galaxy. On top of that, the trees themselves are doctors.
• InCryptid: Johrlac blood is a natural painkiller/antibiotic.
• Nightshade Trilogy: The blood of the Guardians (wolf shapeshifters) can heal whoever drinks it, but only if it is offered by said Guardian as a gift.
• Pit Dragon Chronicles: Dragon saliva is healing for human wounds and human saliva is healing for dragon wounds. In a subversion, dragon blood is acidic and burns human flesh.
• The Saga of Darren Shan: Vampires have healing spit. In the prequels, a vampire even runs makeshift hospitals for humans using his saliva and that of two other vampires.
• Semiosis: The sapient Plant Aliens on Pax can synthesize all kinds of chemicals, from complex drugs to deadly poisons. As one of the smartest, Stevland learns to produce fruit containing various human medications.
• The Snow Queen Series: The blood of the mers, a creature native to the planet Tiamat, is harvested to produce the "water of life", an Immortality Inducer. The mers are in danger of being hunted to extinction because of this.
• Star Wars Expanded Universe:
  • Both bacta and kolto — potent healing fluids central to the galaxy's medical industries — are derived from secretions of specific species. Kolto is said to be produced by a huge shark-like fish known as the Progenitor, while Bacta is produced by mixing together cultures of a specific type of bacteria and the secretions of the insectoid species that manufactures its.
  • The Fosh ex-Jedi Vergere uses the Force on a microscopic level to alter the biochemistry of her tears, allowing them to be anything from a fast-acting contact poison to a medication to stop the progression of Mara Jade Skywalker's spore illness. They're dangerous to her unborn son, though, and she has to stop taking them after getting pregnant.
• Stranger Station by Damon Knight: An alien gives a liquid from its body that cures disease on Earth. It turns out that a human is necessary adjacent to the process, because humans are repulsive to the aliens, and the elixir is actually sweat produced out of their agony enduring our presence.
• Tales of the Five Hundred Kingdoms: Unicorns produce a range of healing items. Hair from a dead unicorn prevents illness; hair from a living unicorn not only protects from illness but from evil magic as well. Unicorn horn neutralizes poison, unicorn tears heal mental disorders, and unicorn blood cures diseases and injuries.

Live-Action TV

• Agents of S.H.I.E.L.D.: "T.A.H.I.T.I." reveals that Coulson was resurrected by a drug called GH.325, derived from the bodily fluids of a Kree corpse, codenamed G.H. It is then used to heal Skye's fatal bullet wounds.
• Battlestar Galactica (2003): Hera's hybrid blood temporarily cures Roslin's cancer.
• Earth 2: The Grendlers — squat, roughly humanoid primitive scavengers and traders on Planet G889 — possess saliva with healing properties so powerful that it can cure humans of basically anything.
• Farscape:
  • "...Different Destinations": Fellip urine has healing properties (or at least, can numb pain). Naturally, this being Farscape, it's Played for Laughs.
  • The Virtual Zhaan's "milk" in the episode "John Quixote". However, this is all part of a virtual reality game and may not be based in the reality of the show's setting.
• Forever Knight:
  • "If Looks Could Kill": A vampire doctor used injections of her own blood as a "miracle youth-restoring treatment" marketed to rich elderly women. Unfortunately the users suffer from homicidal outbursts, and Rapid Aging if the treatments stop.
  • "Fever" has an undeadly virus going about the vampire community. Originally contracted by sucking the blood of a lab rat which had been used to test an HIV vaccine, it can only be cured by sucking the blood of an AIDS victim.
• Heroes: Claire's blood turns out to be a miracle cure.
• The Immortal (1969): A man discovers that his blood not only makes him immortal but can cure diseases in any person it's transfused into.
• Lexx: Protoblood (implied to be produced by the alien Insects) can reanimate the dead as servants of His Divine Shadow.
• Midnight, Texas: Vampire blood can be ingested by humans, doing so will temporarily dramatically enhance their healing and resilience. However, it has the side effect of creating a Psychic Link between them and the Vampire from whom the blood was taken.
• The Outer Limits (1995): In "The Grell", the Grell, a race of humanoid aliens held in slavery by humanity on Earth, have saliva with rapid healing properties.
• Star Trek: Enterprise:
  • "Dawn": When Trip is stranded on a hostile planet with an Arkonian pilot, he discovers that Arkonian saliva can heal wounds rapidly.
  • Dr. Phlox takes advantage of the medicinal properties of several non-sentient alien species in his sickbay.
• True Blood: Vampire blood. In addition to being an addictive psychoactive stimulant/steroid/win-button, it can be ingested by injured humans to bring them back from the brink of death.
• The Vampire Diaries: A human who drinks vampire blood will temporarily gain a slightly weaker version of the Healing Factor that vampires have, allowing said human to recover from otherwise fatal injuries. Similarly, the blood of the Original hybrid, Klaus, can be used to heal a normal vampire from a werewolf bite, which is typically fatal to non-Original vampires.
• War of the Worlds (1988): In one episode, the aliens reduce a number of human brains into a drop of fluid that cures them of the flu.

Music

• Silverchair: The Music Video for "Freak" has an old woman paying to consume sweat produced by the band while they are playing. Not satisfied with just the sweat causing her to be de-aged, she demands more. This causes her to mutate alien features such as yellow-green eyes, purple lips and bony ridges. She does seem quite happy with the changes.

Myths & Religion

• The Celts had a belief in the healing power of saliva, which is where the idea of "kiss it better" originates.
• In the medieval German epic Nibelungenlied, the hero Siegfried becomes invulnerable by bathing in a dragon's blood.
• In a folk tale from Southern Italy, the protagonist is an enchanted woman who lives in a rosemary plant (A Wizard Did It) and falls in love with the Prince who buys the rosemary. However, when the Prince's jealous sisters find her and give her a beating, she falls ill and the rosemary wilts. The gardener responsible flees the palace and, in the forest, overhears the discussion a couple of Dragons are having about the rosemary maiden, and one of them confess that the only remedy to save her is a mixture made from the blood from his throat and grease from the other dragon's hide. As soon as the two fall asleep, the gardener kills them, recovers the blood and grease and use it to heal the rosemary plant and save the girl.
• Unicorn blood is held to have healing properties in several myths.
• In the Russian folk tale about Yeruslan Lazarevich, one of the hero's adventures is about curing his family who were blinded (either by a villain or due to sitting too long in a dark dungeon where said villain threw them). The cure required is the bile of a certain evil king.

Tabletop Games

• Dungeons & Dragons:
  • In the 3rd Edition supplement Creature Collection, the ewe of the Amalthean Ram gives milk that neutralizes non-magical poisons and diseases and heals the wounds of anyone who drinks it.
  • The Dragon Magazine #332 article "Cutting up the Dragon" describes how dragon bone marrow can be used to create a salve that can heal the diseases of those whose skin it's applied to.
• Gamma World 1st Edition adventure GW1 Legion of Gold. The PCs can encounter a parn nest in the buggems' underground lair. If drunk, the sweet smelling fluid in the parns' egg sacs heals 3-18 Hit Points of damage per liter.
• Hc Svnt Dracones: One of the genetic reclamations available to Canidae characters is Healing Saliva.
• Metamorphosis Alpha: In Dragon Magazine article "An Alternate Beginning Sequence for Metamorphosis Alpha'', one of the alternate mutations is "Immortal". Transfusing an immortal's blood into another creature heals between two and forty Hit Points of damage to the recipient.
• Pathfinder: Troll livers can be used to create healing items, taking advantage of their former owners' powerful Healing Factor.
• Rifts: The blood of the Cactus People can be used to brew Healing Potions.
• The Unofficial Hollow Knight RPG: Bugs with the Blood of the Ancients Trait have blood with miraculous healing properties, allowing the bug to sacrifice one Heart in order to let another bug drink their blood, giving the drinker one Lifeblood Heart. The Primal Ichor trait upgrades this so that it instead grants the drinker two Lifeblood Hearts, heals attribute damage, and clears status conditions and Damage Over Time effects.
• Warhammer: While consuming troll flesh is normally fatal, as it's toxic and its regenerative properties will cause it to grow and expand in your belly, ogre butcher-wizards can consume troll guts as part of a spell that imbues either themselves or other ogres with the troll's supernatural healing.
• The World of Darkness:
  • In Vampire: The Requiem and Vampire: The Masquerade, vampire saliva can heal skin punctures and remove the signs of fang puncture marks.
  • Hunter: The Vigil features the Cheiron Group, a conspiracy of monster hunters backed by an international pharmaceutical group that looks to capture and research supernatural creatures, and apply that research into developing new medicines. In the short term, their Endowment also equips their agents with biological enhancements like stolen vampire saliva glands grafted to agents to help them heal, and werewolf adrenal extracts to fight beyond human limits.
  • Leviathan: The Tempest: Leviathans with access to the Hydra's Rebirth channel can secrete a fluid that will heal wounds, cleanse toxins, cure sicknesses, and even reverse menopause and cure infertility. However, the ichor of an eldritch god is not wholly safe: each draught risks causing various deleterious mutations to the drinker (and of course his subsequent offspring).

Video Games

• Bloodborne: Old Blood, found within the Pthumerian Catacombs, can heal any injury or disease and lead to the city of Yharnam become famed for healing and medicine. The player character is a pilgrim visiting the city to be cured of an unknown illness. Not only that, the blood echoes stay inside the drinker so that their blood also provides healing. When the game begins, blood drinking is so common that Yharnam residents drink blood instead of wine. Sadly, blood echoes can also turn people into beasts on the Night of the Hunt, an astronomic event, requiring the Hunters to purge them.
• Disgaea 4: A Promise Unforgotten: Angel blood can cure any disease.
• Fate/Grand Order:
  • The saliva of Oryou (Ryoma's dragon steed) can heal people.
  • Asclepius mentions that the blood from the right side of the Gorgon for his resurrection potion and Noble Phantasm, Resurrection Fraught Hades. As such, she gets excited should you have summoned Gorgon, as it means he'll be able to recreate his most prized invention.
• Final Fantasy XIV:
  • Owing to the magical nature of the setting, many alchemical concoctions require animal products. For instance, wolf fangs can be used to make spine drops to treat cases of temporary paralysis. Imp wings can be turned into ethers to restore one's reserves of aether to help sling extra spells. The humours of a jellyfish can be distilled into a potion that induces Forced Sleep when consumed or inhaled.
  • Due to the harsh climate and terrain of Gyr Abania, many Ala Mhigans turn to natural remedies made of bodily products of the beasts that inhabit the area to treat illness.
    • An Ala Mhigan remedy for a poisoned wound consists of taking the horn from an antelope and grinding it with water to make a paste that is rubbed onto the wound. The Warrior gains the trust of Meffrid, a captain in the Ala Mhigan Resistance, by securing this remedy for one of his men after the elementals barred the conjurers of Gridania from providing aid.
    • The horns of muud suuds, a species of hulking Horned Humanoid found throughout Gyr Abania, can be ground into a powder and boiled in water to produce a flavorful, nutritious, and energizing broth with properties akin to coffee thanks to a recipe from the Near East. Meanwhile, the tallow of a muud suud has an intensely unpleasant and hard-to-wash out scent akin to chocobo dung, which Ala Mhigan scouts use to keep man-eating Qiqirn and other beasts away via Sensory Overload.
      Resistance Fighter: You would never guess something so wonderful could come from a creature so horrid, but such dishes made from the horns and bones of animals are quite common in Gyr Abania. Aside from their distinctive flavors, they all have varying effects that are quite beneficial to one's health.
  • Subverted by some other folk remedies mentioned in the series. Legends of mermaid flesh granting immortality are nothing more than myths, but it doesn't stop those who are Rich in Dollars, Poor in Sense to try to cheat death by trying to eat "mermaid flesh". This nearly gets Alpa killed when Kageyama has Nhaza'a Jaab kidnap her to sell her to the highest bidder.
• Hollow Knight has Lifeblood Seeds, tiny creatures filled with a bright blue liquid called Lifeblood. Lifeblood invigorates the body and makes the drinker feel stronger, which mechanically translates to temporary bonus Masks when you kill one.
• Illusion of Gaia: Unspecified body fluids from the Sand Fanger are thought to cure diseases. Lance uses some to cure his father's memory loss.
• The Legend of Zelda:
  • The Legend of Zelda: Breath of the Wild:
    • Cooking certain animals together with monster parts creates elixirs with various effects.
    • Molduga guts are said to possess healing properties, and one sidequest has you retrieve them to give to a Gerudo woman who needs them to help her sick husband.
  • The Legend of Zelda: Tears of the Kingdom: Similarly to Molduga guts in the previous game, the viscera of Gleeoks, three-headed dragons with elemental Breath Weapons, are a valuable component for medicine. The same Gerudo woman from the previous game needs to get her hands on this other ingredient, since her husband is sick again.
• Pokémon:
  • Chansey and Blissey have an egg-like object they produce in their pouch. Eating it brings happiness and health to whoever does so. Its signature move^note except for a few other lines in some games Soft-Boiled has the egg used to heal half the user's maximum HP, or give away some of its HP to a party member in the overworld.
  • Miltank produces and is farmed for its Moomoo Milk, which heals Pokemon by 100 HP. Its original signature move (which later was learnable by the Skiddo line) involves the Pokemon drinking its own milk to heal by half their maximum HP.
• Spelunky HD: Queen bees, when killed, drop royal jelly that restores a whopping 4 HP (6 in Spelunky 2) to the spelunker who picks it up.
• Subnautica: The mysterious enzyme needed to cure the Kharaa plague comes from the gastric fluids of the Sea Emperor Leviathan.
• Xenoblade Chronicles X features a side mission to collect a scale from the Telethia, a dragon-like megafauna known throughout Mira as the planet's guardian. A single scale is said to act as a Panacea and cure anything. However, you have to fight it and test your worth to obtain the scale, which the story treats as a death sentence. This side mission is ultimately Played for Laughs when you discover that Tatsu's rival Tora just needed to cure some rather bad indigestion and milked it as a life-threatening ailment.

Webcomics

• Cross Time Café: Unicorn boogers have undisclosed magical properties. Oompa Loompas wind up chasing White Pony around, trying to gather said nasal secretions.
• The Order of the Stick: Troll blood retains its Healing Factor when it's applied to a wound, though it creates patches of troll flesh where it heals. As trolls are generally disregarded as monsters fit only for killing, this property isn't widely known.
• Starslip parodies this. Cirbozoids, due to their Bizarre Alien Biology, produce a mind-bogglingly wide variety of secretions with an equally wide variety of uses. For any medical condition in other species (or for that matter, any non-medical emergency), the Cirbozoids secrete something that serves as an at least temporary solution.
• Zombie Ranch: The Undead are factory-farmed for the wonder-drug compounds in their blood.

Web Original

• Mystery Flesh Pit National Park: The Flesh Pit's "ballast bulbs" secrete a fluid known as amniotic ballast which can treat both cancer and dementia but has been known to cause addictions, with many suffering from "depressive withdrawal periods" after the park was shut down in 2007.

Western Animation

• Adventure Time: In "Escape from the Citadel", the blood from the Guardians of the Citadel can not only heal wounds, but also regrow flesh and muscles — not missing limbs, though. This can extend to an entire skeleton, as the Lich is unfortunate enough to experience.
• American Dad!: In "Big Trouble in Little Langley", Francine's mother, Ma Ma Ling, uses monkey dung to treat Haley's cold sore, which she calls "whore lip". It does not seem to actually work, though.
• Disenchantment has elf blood, an ingredient for the Elixir of Life which, when inserted into the Eternity Pendant, can grant the wearer immortality or heal them from any injury or other affliction. However, it has to be blood from a full-blooded elf, or it will not work.
• Drawn Together: When Wooldoor learns about the joys of masturbation, it turns out that the resulting "clum babies" can heal any illness... as well as being a great lubricant for squeaky hinges!
• In The Fairly OddParents!, drinking fairy sweat temporarily gives the ability to make one wish and have it come true.
• In Dragons: Race to the Edge, a rare species of dragon, the Buffalord, has medicinal saliva which is the only known cure for the disease known as the Scourge of Odin. However, this is only after it chews a special type of grass.
• The Simpsons: In "Treehouse of Horror XX", Bart is immune to a zombie plague. The other still-human residents of Springfield want to kill, cut up and eat him in order to acquire his immunity. They eventually decide to have him bathe in a soup for them to eat in order to acquire the immunity without killing him.
• Steven Universe:
  • The title character's spit can heal injuries or illness (even damage to inanimate objects) and turn plants into Plant Mooks. His mother, Rose Quartz, could do the same with her tears.
  • The Diamond Authority's sweat^noteOr more precisely, steam that's condensed on their body — full gems don't really sweat can bring some materials to life, and is part of what other gems are made of. It's likely that Steven's spit and Rose's tears are a different form of the same substance. Combining the essence of all four Diamonds together cures gem corruption and can repair a shattered gem from their fragments.

Real Life

• Vampire bat saliva contains anticoagulants, so that the bats' prey bleed longer and they can lap up more blood per feeding. The anticoagulants have been investigated for treating stroke patients, but they do not work any better than standard treatment with drugs that are easier to get.
• Early versions of hormone replacement therapy used things like testosterone extracted from bull testicles and estrogens concentrated from pregnant mares' urine (the latter marketed as "Premarin"). Now these are also more commonly synthesized in a laboratory.
• Enzymes extracted from the blood of horseshoe crabs are used to detect bacterial toxins in medical research. This has led to the practice of catching the crabs, drawing a portion of their blood (which is bright blue), and then releasing them. The enzyme can be synthesized, but making it from scratch has been more expensive then catch-and-release for the crabs.
• Medical insulin was originally isolated from the pancreases of cows and other animals. It's now human-analog insulin produced by engineered bacteria.
• Human lungs secrete pulmonary surfactant to keep all the little air-exchange sacs from sticking closed. If you are not producing enough on your own; you may be treated to sprays of replacement surfactant down your throat. It's made from the surfactant in cow, pig, or sheep lungs. Usually, this just involves getting the overstock lungs from a slaughterhouse and chopping them up very fine.
• In traditional Chinese medicine, animal parts and fluids are believed to cure various ailments. However, there's very little scientific evidence to suggest any of it actually works better than a placebo, and unfortunately, it also puts a high bounty on several endangered species. This has particularly had a negative impact on Chinese paleontology since local dinosaur fossils, which are often particularly well-preserved, were held to be the bones of dragons and ground into fine powder for the same medicinal purposes.

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