42 entries
Medicine
Ulcers, appendixes, and tonsils: medical facts your school confidently taught that clinical evidence overturned.
Changes here run from 1992 to 2026.
- Disproved23
- Updated14
- Replaced5
- DisprovedNot in textbooks yet
TaughtMedicines work by binding a target protein and blocking it, like a key jammed in a lock. The drug has to stay bound to keep working, and proteins the body considers 'undruggable', with no good pocket to grab, are simply out of reach.
NowOn 1 May 2026 the FDA approved vepdegestrant (Veppanu), the first PROTAC ever authorized anywhere. Instead of blocking its target, it tags the protein for the cell's own disposal machinery, so the protein is destroyed rather than merely occupied.
- UpdatedNot in textbooks yet
TaughtThe CRISPR therapy Casgevy that can functionally cure sickle cell disease was approved for people twelve and older. Young children, who suffer the most damage from the disease early on, were left waiting on the sidelines.
NowOn 1 July 2026 the FDA expanded Casgevy (exagamglogene autotemcel) to children as young as two with severe sickle cell disease or transfusion-dependent beta thalassemia: the first one-time genetic therapy approved for that age group, adding roughly 5,500 eligible children in the US.
- UpdatedNot in textbooks yet
Cerebral folate deficiency has no treatment
Changed in2026TaughtWhen a genetic fault blocks folate from reaching the brain, children develop seizures, movement disorders, and severe developmental delay. It is a devastating, untreatable condition; you manage the symptoms and little else.
NowOn 10 March 2026 the FDA approved Wellcovorin (leucovorin calcium) as the first treatment for cerebral folate transport deficiency caused by variants in the FOLR1 gene. Leucovorin is a form of folate that can slip into the brain by a different route, bypassing the broken transporter.
- DisprovedNot in textbooks yet
TaughtWhen a child is born deaf because of a genetic defect, the ear is broken at the source. A cochlear implant can route sound around the damage, but there is no way to fix the underlying biology and give the ear its own hearing back.
NowOn 23 April 2026 the FDA approved Otarmeni (lunsotogene parvec), a one-time gene therapy for deafness caused by variants in the OTOF gene. It delivers a working copy of the gene to the inner ear, and most treated patients gained usable hearing, some reaching normal levels, including whispers.
- UpdatedNot in textbooks yet
TaughtArginase 1 deficiency lets the amino acid arginine build to toxic levels, causing stiffness, seizures, and developmental regression. There is no drug for it. Management means a severely protein-restricted diet, for life, and it is rarely enough.
NowOn 23 February 2026 the FDA granted accelerated approval to Loargys (pegzilarginase), an engineered enzyme injected to break down the excess arginine the body cannot clear on its own, the first therapy that directly targets the disease.
- UpdatedNot in textbooks yet
For early bladder cancer, BCG is the only option, and nothing has improved on it in decades
Changed in2026TaughtHigh-risk bladder cancer that hasn't invaded the muscle is treated by putting BCG, a tuberculosis vaccine, into the bladder. It has been the standard since the 1970s, and despite the cancer often coming back, nothing has been added to it in a generation.
NowOn 28 May 2026 the FDA approved durvalumab (Imfinzi) in combination with BCG for high-risk, non-muscle-invasive bladder cancer: the first immunotherapy combination for the disease, and the first genuinely new approach layered onto BCG in decades.
- UpdatedNot in textbooks yet
Nothing can reach the brain damage of Hunter syndrome
Changed in2026TaughtIn Hunter syndrome, a missing enzyme lets sugary molecules pile up in cells throughout the body and the brain. Enzyme replacement can help the body, but the replacement enzyme cannot cross the blood-brain barrier, so the cognitive decline is untouchable.
NowOn 25 March 2026 the FDA approved Avlayah (tividenofusp alfa), an enzyme replacement engineered to cross the blood-brain barrier: the first treatment for Hunter syndrome aimed at its neurological damage, and the first FDA approval for the disease in nearly twenty years.
- DisprovedNot in textbooks yet
TaughtThe biologics that clear moderate-to-severe psoriasis are large antibody proteins. Swallow one and your gut digests it like food, so they only work as injections. A pill that targets the same pathway is not chemically possible.
NowOn 18 March 2026 the FDA approved Icotyde (icotrokinra), the first oral IL-23 pathway drug for plaque psoriasis. It is a small engineered peptide designed to survive the gut and block the same target the injected biologics hit.
- UpdatedNot in textbooks yet
TaughtHigh blood pressure is treated with the same handful of drug families your parents took: diuretics, ACE inhibitors, ARBs, calcium-channel blockers, beta-blockers. Nothing mechanistically new has arrived in decades, and for resistant patients the cupboard is bare.
NowOn 18 May 2026 the FDA approved baxdrostat (Baxfendy), an aldosterone synthase inhibitor, the first mechanistically new class of blood-pressure drug in decades. It blocks the enzyme that makes aldosterone, a hormone that drives hard-to-treat hypertension.
- UpdatedNot in textbooks yet
TaughtFocal segmental glomerulosclerosis scars the kidney's filters and marches toward dialysis or a transplant. There is no drug approved specifically for it; doctors borrow steroids and blood-pressure medicines off-label and hope.
NowOn 13 April 2026 the FDA gave full approval to sparsentan (Filspari) as the first medicine ever approved specifically to treat FSGS, based on the phase 3 DUPLEX trial showing it reduced the protein leakage that drives the disease.
- DisprovedNot in textbooks yet
TaughtTriple-negative breast cancer lacks the three receptors that targeted drugs aim at, which is what 'triple-negative' means. With no target to hit, treatment falls back on general chemotherapy, and outcomes are poor.
NowOn 22 May 2026 the FDA approved Datroway (datopotamab deruxtecan), the first targeted therapy to beat chemotherapy on survival in first-line metastatic triple-negative breast cancer. It homes in on a protein called TROP2 and delivers a chemotherapy payload directly to the tumor cells.
- DisprovedNot in textbooks yet
A gene therapy has to be developed for a whole patient population, never for one child
Changed in2025TaughtDeveloping a gene-editing therapy takes many years and enormous cost, so it only makes sense for diseases shared by thousands of patients. A treatment designed and manufactured for a single individual's exact mutation is science fiction.
NowIn May 2025 a team at Children's Hospital of Philadelphia treated an infant known as KJ Muldoon, who had a severe CPS1 urea-cycle disorder, with a CRISPR base-editing therapy custom-built for his specific mutation, from diagnosis to dosing in about six months. It was the first personalized in-vivo gene-editing medicine made for one person.
- UpdatedNot in textbooks yet
Nothing you can be given lowers your risk of dementia
Changed in2025TaughtDementia is a matter of genes and age. There is no vaccine and no ordinary medication that measurably lowers a person's chance of developing it; prevention is limited to vague lifestyle advice.
NowIn April 2025 a study in Nature exploited a vaccine-eligibility cutoff in Wales as a natural experiment and found that people who received the shingles vaccine were about 20% less likely to be diagnosed with dementia over the following seven years, the strongest causal-leaning evidence yet that a widely used vaccine is associated with lower dementia risk.
- DisprovedNot in textbooks yet
TaughtThere is no HIV vaccine and no long-lasting way to prevent infection. Prevention comes down to condoms or, more recently, a pill taken every single day without fail.
NowIn June 2025 the FDA approved lenacapavir (Yeztugo), an injection given just twice a year that prevented HIV in essentially everyone who received it in trials, close to 100% effective.
- Updated
TaughtThe U.S. Preventive Services Task Force recommended that routine screening mammograms begin at age 50. For women in their 40s, whether to screen was an individual decision to weigh with a doctor, not a blanket recommendation.
NowOn 30 April 2024, the USPSTF issued a final recommendation that all women at average risk begin screening mammography at age 40, every other year, through age 74, moving the universal starting age down a full decade.
- Disproved
TaughtNon-alcoholic steatohepatitis (NASH), the serious, scarring form of fatty liver disease, has no medication. Despite affecting millions, the only treatment is losing weight through diet and exercise; every drug candidate had failed in trials.
NowOn 14 March 2024, the FDA approved resmetirom (Rezdiffra) for NASH, now called MASH, with moderate-to-advanced liver fibrosis. It is the first drug ever approved for the disease, after decades in which every candidate fell short.
- Updated
You cannot transplant an animal's organ into a human
Changed in2024TaughtTransplants have to come from human donors. An organ from another species would be rejected by the immune system within minutes, so cross-species transplants are impossible.
NowOn 16 March 2024, surgeons at Massachusetts General Hospital transplanted a gene-edited pig kidney into a living patient, the first time an animal organ was placed in a living human. Earlier gene-edited pig hearts and kidneys had been tried in brain-dead recipients and, in 2022, in one living heart patient.
- Updated
Gene editing is experimental, with no approved therapy
Changed in2023TaughtCRISPR is a remarkable laboratory tool for editing DNA, but using it to treat patients is years away and purely experimental. No gene-editing therapy has been approved for use in people.
NowOn 8 December 2023 the US FDA approved Casgevy, a CRISPR-based therapy for sickle cell disease, the first approved medicine that edits a patient's DNA. The UK had authorized it weeks earlier.
- Disproved
Nothing can slow Alzheimer's, only ease the symptoms
Changed in2023TaughtThere is no way to slow or stop Alzheimer's disease. The available drugs treat symptoms like memory loss and agitation for a while, but the underlying decline is unstoppable.
NowIn 2023 the FDA fully approved lecanemab (Leqembi), an antibody that clears amyloid from the brain and modestly slows cognitive decline, the first treatment shown to change the course of the disease rather than only its symptoms.
- Updated
TaughtNaloxone (Narcan) can reverse an opioid overdose in minutes, but it is a medication; you get it through a pharmacist, a prescription, or a special standing order. It is not something you buy off a shelf like aspirin.
NowOn 29 March 2023 the FDA approved Narcan nasal spray for over-the-counter sale, the first naloxone product cleared for use without any prescription, clearing the way for it to be stocked in supermarkets, convenience stores, vending machines, and online.
- Disproved
There is no pill for postpartum depression
Changed in2023TaughtPostpartum depression is treated with the same general antidepressants used for everything else, which take weeks to work. There is no medication designed specifically for it, and the one dedicated drug that existed required a 60-hour IV infusion in a hospital.
NowOn 4 August 2023 the FDA approved Zurzuvae (zuranolone), the first oral medication developed specifically for postpartum depression, a once-daily pill taken for 14 days that can improve symptoms within days rather than weeks.
- Disproved
There is no vaccine for RSV
Changed in2023TaughtRespiratory syncytial virus (RSV) sends tens of thousands of older adults and infants to the hospital every year, and there is nothing to prevent it. Sixty years of vaccine attempts had failed (one 1960s trial made the disease worse) so RSV was the textbook example of a virus we could not vaccinate against.
NowIn May 2023 the FDA approved Arexvy, the world's first RSV vaccine, for adults 60 and older, followed within weeks by a second. In trials a single dose cut the risk of symptomatic RSV illness by about 83% and severe illness by roughly 94%.
- Replaced
TaughtOnce you reach middle age, a baby aspirin daily is basic preventive care. It thins the blood and protects against heart attack and stroke, with essentially no downside.
NowThe US Preventive Services Task Force reversed the recommendation in 2022. For adults 60 and over with no cardiovascular disease, do not start daily aspirin: the bleeding risk outweighs the benefit. For ages 40 to 59 it is now an individual decision with a doctor, not a default.
- Updated
TaughtTransplants come from human donors. The human immune system destroys animal organs within minutes to hours, 'hyperacute rejection', so putting a pig's heart into a living person is a fantasy that has never been, and may never be, achieved.
NowOn 7 January 2022, surgeons at the University of Maryland transplanted a genetically modified pig heart into David Bennett, a living man with end-stage heart failure. The organ was not rejected on the table; it beat and sustained him for two months.
- Disproved
TaughtCRISPR gene editing works in the lab: you take cells out of a patient, edit them in a dish, and return them. You cannot inject the editing machinery into a living person and have it find and fix the right gene inside the body; that is far too imprecise and dangerous.
NowIn June 2021, Intellia and Regeneron reported in the New England Journal of Medicine the first successful in-vivo CRISPR editing in humans: a single intravenous infusion of NTLA-2001 switched off a disease gene in the livers of patients with transthyretin amyloidosis, cutting the harmful protein by up to 96%.
- Disproved
There is no vaccine for malaria
Changed in2021TaughtMalaria kills hundreds of thousands of people a year, most of them young children, and there is no vaccine against it. The parasite is too complex and shape-shifting a target; a century of attempts had produced nothing usable.
NowIn October 2021, the World Health Organization recommended the first malaria vaccine, RTS,S (Mosquirix), for widespread use in children across sub-Saharan Africa, the first vaccine ever recommended against a human parasitic disease.
- Disproved
TaughtAntibiotics do nothing against viruses, and for most viral infections there is no cure at all; you treat the symptoms and wait. Coronaviruses in particular have never had a single approved drug to fight them.
NowOn 22 October 2020 the FDA fully approved Veklury (remdesivir) for treating COVID-19, the first drug ever approved to treat any coronavirus infection. It is an antiviral that jams the machinery the virus uses to copy its own genome.
- Disproved
No vaccine has ever been made from messenger RNA
Changed in2020TaughtEvery vaccine works by showing your immune system a weakened, killed, or fragmented version of a germ, grown in eggs or cell cultures over many months. Messenger RNA is far too fragile to use as a medicine, and no vaccine built from genetic instructions alone has ever been approved for anyone.
NowOn 11 December 2020 the FDA authorized the Pfizer-BioNTech COVID-19 vaccine: the first mRNA vaccine ever cleared for use in people, with Moderna's following a week later. It carries a strand of messenger RNA that instructs your own cells to make one harmless viral protein, training immunity without any piece of the virus itself.
- Disproved
There is no cure or approved treatment for Ebola
Changed in2020TaughtEbola is a near-certain death sentence. Doctors can only offer supportive care (fluids, oxygen, treating whatever else goes wrong) and hope. No drug has ever been approved to treat the virus itself.
NowOn 14 October 2020 the FDA approved Inmazeb, a cocktail of three monoclonal antibodies from Regeneron, the first approved treatment for Zaire ebolavirus. A second drug, Ebanga, was approved that December. In the trial that tested them, they roughly halved deaths, and cut them far more when given early.
- Updated
TaughtYou are only 10 percent human. Microbial cells outnumber your own cells by ten to one, a striking statistic repeated in every biology and health class.
NowThe ratio is closer to 1.3 to 1, and it fluctuates around 1 to 1 depending on when you last used the bathroom. A single bowel movement can shift it. You are roughly half human by cell count, which is still remarkable but not the same claim.
- Replaced
TaughtRolled your ankle? RICE. Rest it completely, ice it, compress it, elevate it. Inflammation is the enemy and ice is how you fight it.
NowGabe Mirkin, the doctor who coined RICE in 1978, publicly retracted the rest and ice components in 2015. Current guidance favors early controlled movement and loading, and inflammation is now understood as part of healing rather than something to suppress.
- Replaced
Shake off a head knock and get back in the game
Changed in2013TaughtYou got your bell rung. If you did not lose consciousness, it is not a real concussion. Count fingers, walk it off, and get back out there. Being tough about it is part of the sport.
NowLoss of consciousness happens in a minority of concussions and is not required for diagnosis. Any suspected concussion means immediate removal from play with no same-day return, and all 50 US states passed youth concussion laws between 2009 and 2014.
- Replaced
Tonsils should come out if they give you trouble
Changed in2011TaughtRecurrent sore throats mean the tonsils come out. It is a rite of passage, you get ice cream, and the tonsils are not good for anything anyway.
NowTonsillectomy rates fell dramatically as evidence showed limited benefit for most children with recurrent throat infection. The 2011 and 2019 clinical practice guidelines set specific thresholds, seven episodes in a year, five a year for two years, or three a year for three years, and recommend watchful waiting otherwise.
- Disproved
The MMR vaccine might cause autism
Changed in2010TaughtA 1998 Lancet paper raised a possible link between the MMR vaccine and autism. The question was presented as open and legitimately debated, and worth being cautious about.
NowThe paper was retracted in full by The Lancet in February 2010, and Andrew Wakefield was struck off the UK medical register in May 2010 for dishonesty and unethical conduct. Studies covering millions of children have found no link. The research was fraudulent, not merely mistaken.
- Disproved
Grief has five stages
Changed in2007TaughtGrief proceeds through five stages in order: denial, anger, bargaining, depression, acceptance. If you are stuck in a stage, or skipping one, something is wrong with your grieving.
NowThe stage model has never been supported by good evidence. Grief is highly variable, and the most common trajectory is resilience: most bereaved people do not pass through fixed stages at all. Elisabeth Kübler-Ross's 1969 model described dying patients, not the bereaved, and she said so.
- Disproved
The appendix is a useless leftover
Changed in2007TaughtThe appendix is a vestigial organ, a shrivelled remnant of a plant-eating ancestor's gut, with no function at all. Its only role in your life is to occasionally become infected and try to kill you.
NowThe appendix appears to be a reservoir of beneficial gut bacteria, a safe house that helps repopulate the intestine after illness flushes it out. It also carries substantial lymphoid tissue and plays a role in immune function.
- Disproved
Suck the venom out of a snakebite
Changed in2002TaughtSnakebite first aid: cut an X over the fang marks, suck out the venom, and apply a tourniquet above the bite to stop it spreading.
NowDo none of that. Cutting, sucking, extractor pumps, tourniquets, ice, and alcohol all cause harm and remove essentially no venom. Keep the person calm, immobilize the limb at heart level, remove rings, and get to a hospital for antivenom.
- Disproved
Tilt your head back for a nosebleed
Changed in2000TaughtNosebleed? Tip your head back and pinch the bridge of your nose until it stops.
NowLean forward and pinch the soft part of the nose, below the bony bridge, for 10 to 15 minutes without checking. Tilting back sends blood down your throat, where it can cause vomiting or, rarely, be aspirated.
- Disproved
Get antibiotics for that cold
Changed in1998TaughtIf you have a bad cold, a sore throat, or an ear infection, the doctor prescribes antibiotics and you get better. Antibiotics are the answer to being sick.
NowColds are viral, and antibiotics do nothing to viruses. Roughly 28 percent of outpatient antibiotic prescriptions in the US are unnecessary, and antimicrobial resistance was associated with nearly 5 million deaths globally in 2019.
- Disproved
Your deoxygenated blood is blue
Changed in1995TaughtBlood carrying oxygen is red, and blood returning to the heart is blue. That's why your veins look blue, and why the diagram has red arteries and blue veins.
NowHuman blood is never blue. Deoxygenated blood is dark red, close to maroon. Veins look blue because of how skin scatters and absorbs light, not because of what is inside them.
- Disproved
Ulcers are caused by stress and spicy food
Changed in1994TaughtStomach ulcers come from stress, worry, and a hard-driving personality, aggravated by spicy food. The treatment is antacids, a bland diet, and calming down. You will have them for life.
NowMost peptic ulcers are caused by Helicobacter pylori, a bacterium, and most of the rest by NSAIDs like aspirin and ibuprofen. A course of antibiotics cures them. Barry Marshall and Robin Warren won the 2005 Nobel Prize for it.
- Replaced
Put babies to sleep on their stomachs
Changed in1992TaughtLay an infant face-down to sleep. It is safer, because a baby on its back might choke on spit-up, and stomach sleeping is more settled.
NowBack sleeping is the safe position. The American Academy of Pediatrics reversed the advice in 1992 and launched Back to Sleep in 1994. SIDS rates in the US fell by more than half, and healthy infants do not choke on their backs.