Medical mnemonics for USMLE Step 1
Last reviewed October 21, 2026 · 67 mnemonics across 17 systems
How should you use mnemonics for USMLE Step 1?
Use a mnemonic only for facts that have no logic to hang on: lists, sequences, and look-alike names. Learn the mapping from each letter to its fact the same day, then test yourself on it at growing intervals inside your question bank or flashcards. Retire the mnemonic once you can recall the facts without it.
A mnemonic is a retrieval cue, not knowledge. The first time you meet CHEDIAK or the Rule of 4 you store two things: the phrase, and the link from each letter to a clinical fact. The phrase sticks easily; the links are what fade. Spaced review works on the links. Review the mnemonic the day you learn it, again two or three days later, then after a week, and after that only when a question exposes a gap. Flashcards keep the intervals honest, and a question bank that tags misses by system shows which mnemonics need another pass.
Mnemonics backfire in three predictable ways. Letter collision: two mnemonics share a letter and a system, and under exam pressure the C from one list attaches to the fact from the other. False fluency: you can recite the phrase, so you feel you know the topic, but the vignette asks for the mechanism behind one item and the phrase has nothing to say. And misuse: a mnemonic for something with an underlying logic, such as which way potassium moves in acidosis. A mechanism you understand does not decay like a list, and it transfers to questions the mnemonic never anticipated.
StepGenie’s mnemonic posts are listed below, grouped by organ system and counted, so you can see where coverage is dense and where it is thin. Start with the four below, or jump straight to your weakest system.
Which mnemonics should you learn first?
Learn the ones for facts you cannot rebuild from a mechanism. These four are the ones we would hand a student first: each covers a list or a set of look-alike names with no underlying logic to fall back on, and between them they cover neurology, immunology, biochemistry, and renal.
Brainstem Syndromes Mnemonic: Rule of 4 & CN Nuclei
Rule of 4: medial brainstem lesions hit the 4 M's (motor tract, medial lemniscus, MLF, motor nucleus), lateral ones the 4 S's. Plus CN nuclei by level.
Read ImmunologyChediak-Higashi Syndrome Mnemonic: The CHEDIAK Acronym
CHEDIAK: Clumsy chemotaxis, Hypopigmentation, Enlarged granules, Defective degranulation, Infections, Axonal neuropathy, Killer (NK) cells impaired.
Read BiochemistryFamilial Dyslipidemias Mnemonic: Fredrickson Types I–V
Type I chylomicrons (LPL/ApoC-II), IIa LDL receptor, IIb LDL + VLDL, III ApoE2 remnants, IV VLDL, V chylos + VLDL, with xanthoma and pancreatitis clues.
Read RenalCKD Stages by GFR Mnemonic: 90-60-45-30-15 Countdown
G1 ≥90, G2 60-89, G3a 45-59, G3b 30-44, G4 15-29, G5 <15 mL/min. Plus albuminuria A1-A3, CKD vs AKI clues, and which complications appear at each stage.
ReadFeatured posts: selected by the StepGenie editorial team, September 2026. An editorial pick, not a traffic ranking.
All mnemonics by system
Biochemistry11 posts
Biochemistry practice questionsCollagen Types I-IV: Mnemonic, Tissues, Genes & Diseases
Collagen types: I = bone, skin, tendon (OI); II = cartilage, vitreous; III = vessels, reticulin (vascular EDS); IV = basement membrane (Alport, Goodpasture).
Copper Deficiency Mnemonic: Zinc, B12 Mimic, Menkes/Wilson
Copper deficiency mimics B12: posterior-column myelopathy, iron-refractory anemia, neutropenia. Causes: zinc excess, gastric bypass. Menkes vs Wilson.
Electron Transport Chain Mnemonic: Order & Inhibitors
ETC order NADH → I → Q → III → cyt c → IV → O₂, FADH₂ via II. Proton pumps 4-0-4-2. Rotenone, antimycin A, cyanide/CO, oligomycin; uncouplers DNP, aspirin.
Enzyme Cofactors Mnemonic: B Vitamins and Their Enzymes
TPN FAD CoA: thiamine (TPP), pyridoxine (PLP), niacin (NAD+), riboflavin (FAD), pantothenate (CoA), then biotin, folate, B12 and metal cofactors.
Familial Dyslipidemias Mnemonic: Fredrickson Types I–V
Type I chylomicrons (LPL/ApoC-II), IIa LDL receptor, IIb LDL + VLDL, III ApoE2 remnants, IV VLDL, V chylos + VLDL, with xanthoma and pancreatitis clues.
Fructose & Galactose Metabolism Mnemonic: 4 Disorders
Kinase is kind: fructokinase loss is benign; galactokinase loss, cataracts. Aldolase B loss: hypoglycemia after fruit. GALT loss: jaundice, E. coli sepsis.
Niemann-Pick Disease Mnemonic: Types A/B vs C, Foam Cells
FOAMY mnemonic: foam cells, organomegaly, acid sphingomyelinase, macular cherry-red spot, young death (type A). Type C: NPC1/NPC2 and vertical gaze palsy.
Pompe Disease Mnemonic: Acid Maltase, Cardiomegaly & ERT
Pompe disease (GSD II): lysosomal acid maltase (GAA) deficiency. Infant cardiomegaly, hypotonia, macroglossia; late-onset limb-girdle weakness; ERT.
PVT TIM HALL: Essential Amino Acids Mnemonic and Table
The 9 essential amino acids (PVT TIM HALL adds arginine), 11 nonessential, conditionally essential Tyr and Cys, and why Leu and Lys are purely ketogenic.
Pyruvate Dehydrogenase Cofactors Mnemonic & Regulation
Tender Loving Care For Nancy: TPP (B1), lipoic acid, CoA (B5), FAD (B2), NAD+ (B3). How PDH is switched on and off, plus deficiency, thiamine and arsenic.
Translation: Initiation, Elongation & Termination Mnemonic
Initiation: initiator tRNA in the P site. Elongation: A-site entry, rRNA peptide bond, EF-G/eEF2 translocation. Termination: release factor reads UAA/UAG/UGA.
Biostatistics1 post
Biostatistics & Epidemiology practice questionsCardiovascular7 posts
Cardiology practice questionsACE Inhibitors vs ARBs Mnemonic: Cough, Angioedema & K+
ACE: Angioedema, Cough, Elevated K+. ACE inhibitors raise bradykinin (cough, angioedema); ARBs don't. Both raise K+ and creatinine and are teratogenic.
Acronym trick for Aortic stenosis
High-yield aortic stenosis mnemonic: “AS = A SLOW Exit.” Learn classic murmur, maneuvers, carotid pulse clues, and USMLE facts fast.
CAD Risk Factors Mnemonic: Modifiable vs Non-Modifiable
CAD HITS mnemonic for coronary artery disease risk factors: modifiable vs non-modifiable, 2026 ACC/AHA risk enhancers and a worked USMLE question.
HFrEF vs HFpEF Mnemonic: Fat vs Thick, S3 vs S4
HFrEF: EF 40% or less, a FAT dilated LV that can't pump, S3, four mortality-lowering drugs. HFpEF: EF 50% or more, a THICK stiff LV that can't fill, S4.
Pheochromocytoma Mnemonic: Episodic HTN & Alpha First
5 P's: pressure, pain (headache), perspiration, palpitations, pallor. Metanephrines first, alpha-block before beta, and why the rule of 10s is outdated.
Pressure-Volume Loop Mnemonic: Preload, Afterload & Valves
PV loop mnemonic FIRE: fill, isovolumetric contraction, release, ease off. Preload moves EDV; afterload and contractility move ESV. AS, AR, MR, MS loops.
Prosthetic Valve Complications: PATCHES Mnemonic
PATCHES: Paravalvular leak, Anticoagulant bleeding, Thrombosis, Conduction block, Hemolysis, Endocarditis, Structural deterioration. Warfarin, not DOACs.
Dermatology1 post
Dermatology practice questionsEndocrine1 post
Endocrinology practice questionsEthics1 post
Behavioral Science & Ethics practice questionsGenetics2 posts
Autosomal Recessive Inheritance: Pedigrees and 2/3 Rule
Two carrier parents: 1/4 affected, 1/2 carriers. Why an unaffected sibling is a carrier 2/3 of the time, with a Punnett square and the A RARE mnemonic.
Trinucleotide Repeat Disorders: CAG/CGG/CTG/GAA Mnemonic
Hunt My Fragile Friend: Huntington CAG (father), fragile X CGG (mother), myotonic dystrophy CTG, Friedreich GAA. Mechanisms, thresholds, exam traps.
GI5 posts
Gastroenterology practice questionsCholelithiasis Mnemonic: 5 F's, Stone Types & Workup
Fat, female, fertile, forty, fair, plus family history and fast weight loss. Gallstone types, colic vs cholecystitis vs cholangitis, ultrasound first.
Diverticulosis vs Diverticulitis: Mnemonic, CT & Treatment
Diverticulosis: false sigmoid pouches, painless hematochezia. Diverticulitis: LLQ pain, fever, CT to confirm, selective antibiotics, colonoscopy later.
Mnemonic to remember NAFLD/NASH
Quick mnemonic + high-yield USMLE facts to remember NAFLD vs NASH: risk factors, labs, biopsy findings, complications, and management.
Octreotide Mnemonic: Uses, Side Effects & Mechanism
Octreotide (somatostatin analog, SSTR2/5) treats acromegaly, carcinoid and VIPoma; off-label: variceal bleeding, sulfonylurea overdose. Key risk: gallstones.
Pancreatic Pseudocyst: Mnemonic, 4-Week Rule & When to Drain
Pancreatic pseudocyst: fibrous wall, no epithelium, fluid only, over 4 weeks after pancreatitis. Revised Atlanta vs WON, complications and when to drain.
Heme/Onc3 posts
Hematology & Oncology practice questionsHemophilia A vs B Mnemonic: Factor VIII vs Factor IX
A = eight (factor VIII), B = nine (factor IX). Both X-linked with hemarthroses and an isolated high PTT that corrects on mixing. DDAVP helps mild A only.
Megaloblastic Anemia Mnemonic: B12 vs Folate, MMA & Neuro
Megaloblastic anemia mnemonic: B12 = BRAIN, folate = FOOD. Both raise homocysteine; only B12 raises MMA and harms the spinal cord. Exclude B12 before folate.
Platelet Plug Formation Mnemonic: Steps, Receptors & Drugs
Platelet plug mnemonic: Stick (vWF-GpIb), Signal (ADP-P2Y12, TXA2), Stack (GpIIb/IIIa-fibrinogen). Bernard-Soulier, Glanzmann, vWD, aspirin, clopidogrel.
Immunology6 posts
Immunology practice questionsChediak-Higashi Syndrome Mnemonic: The CHEDIAK Acronym
CHEDIAK: Clumsy chemotaxis, Hypopigmentation, Enlarged granules, Defective degranulation, Infections, Axonal neuropathy, Killer (NK) cells impaired.
Common Variable Immunodeficiency (CVID): Mnemonic & Criteria
CVID: B cells fail to become plasma cells, so IgG plus IgA and/or IgM are low and vaccines fail. Sinopulmonary infections, Giardia, ITP, lymphoma; IVIG.
Complement Deficiencies: USMLE Table and Mnemonics
C1/C2/C4 → SLE-like disease, C3 → severe pyogenic infections, C5-C9 → recurrent Neisseria, C1-INH → hereditary angioedema, DAF/CD59 → PNH. Plus CH50/AH50.
Job Syndrome (Hyper-IgE) Mnemonic: FATED & Flowchart
FATED: coarse Facies, cold staph Abscesses, retained baby Teeth, hyper-IgE, Dermatologic (eczema). Dominant-negative STAT3 means few Th17 cells.
Mnemonic to remember Antigen presentation
Master antigen presentation fast: MHC I vs II mnemonics, who presents what, and key USMLE facts like CD4/CD8, TAP, and costimulation.
T-Cell Activation Mnemonic: 3 Signals, Anergy & CTLA-4
Signal 1: TCR binds MHC-peptide (CD4-MHC II, CD8-MHC I). Signal 2: B7 binds CD28, or the cell goes anergic. Signal 3: cytokines steer Th1, Th2, Th17, Treg.
Microbiology5 posts
Infectious Disease practice questionsAcronym trick for Mycoplasma pneumoniae
Quick USMLE mnemonic for Mycoplasma pneumoniae: walking pneumonia, cold agglutinins, no cell wall, and macrolide/doxy treatment—high-yield facts.
Cryptococcus neoformans Mnemonic: India Ink & Pigeons
CRYPTO mnemonic: capsule, India ink halo, pigeon droppings, CD4 <100, high opening pressure. Amphotericin B + flucytosine, fluconazole, serial LPs.
Dermatophytes Mnemonic: MET, KOH Prep & Treatment
MET eats keratin: Microsporum (skin, hair), Epidermophyton (skin, nails, not hair), Trichophyton (all three). KOH shows hyphae; terbinafine for nails.
Haemophilus influenzae Mnemonic: X & V, Hib & Diseases
HaEMOPhilus: epiglottitis, meningitis, otitis media, pneumonia. Needs X (hemin) + V (NAD): chocolate agar, satellites by S. aureus. Type b PRP capsule.
Mnemonic to remember Clostridium perfringens
High-yield mnemonic and quick facts to remember Clostridium perfringens for USMLE: alpha toxin (lecithinase), gas gangrene, and food poisoning.
Neurology6 posts
Neurology practice questionsAcronym trick for Alzheimer disease
Quick USMLE mnemonic for Alzheimer disease: ALZHEIMER acronym with high-yield pathology, genetics, hallmark findings, and key treatments.
Brainstem Syndromes Mnemonic: Rule of 4 & CN Nuclei
Rule of 4: medial brainstem lesions hit the 4 M's (motor tract, medial lemniscus, MLF, motor nucleus), lateral ones the 4 S's. Plus CN nuclei by level.
Medulloblastoma Mnemonic: Vermis, Rosettes & Drop Mets
Midline vermis tumor of kids: small round blue cells, Homer Wright rosettes, CSF drop metastases, 4th ventricle hydrocephalus. Vs pilocytic astrocytoma.
Obstructive Sleep Apnea Mnemonic: STOP-BANG, AHI & CPAP
OSA mnemonic STOP-BANG: snoring, tired, observed apneas, pressure, BMI >35, age >50, neck ≥40 cm, male. AHI 5/15/30 grades severity; CPAP is first-line.
Radiculopathy Mnemonic: C5-C8 & L4-S1 Roots, Reflexes, Tests
C6 thumb, C7 middle finger + triceps, C8 little finger; L4 patellar, L5 big toe + foot drop, S1 ankle jerk. Disc-to-root rules, Spurling, SLR, red flags.
Subacute Combined Degeneration Mnemonic & B12 Flowchart
SCD mnemonic: Spinocerebellar, Corticospinal, Dorsal columns. B12 deficiency raises MMA and homocysteine; folate, copper and nitrous oxide compared.
Pharmacology3 posts
Pharmacology practice questionsAgonist vs Antagonist vs Partial Agonist Mnemonic
Agonists activate, antagonists block, partial agonists cap below max, inverse agonists cut baseline. Competitive: right shift; noncompetitive: lower Emax.
CYP450 Inducers, Inhibitors & Substrates: Mnemonic List
CYP450 inducers (rifampin, carbamazepine, phenytoin, St. John's wort) lower drug levels; inhibitors (azoles, macrolides, ritonavir, grapefruit) raise them.
Mnemonic to remember Bioavailability
Quick USMLE mnemonic for bioavailability (F): definition, first-pass effect, route comparisons, and the AUC formula in a high-yield recap.
Psychiatry3 posts
Psychiatry practice questionsCluster C Personality Disorders: Mnemonic & OCPD vs OCD
Cluster C (anxious/fearful): avoidant fears rejection, dependent needs others to decide, OCPD is ego-syntonic perfectionism, unlike OCD. Psychotherapy first.
Specific Phobia Mnemonic: DSM-5 Criteria, Types & Treatment
Specific phobia: out-of-proportion fear of an object or situation, avoided, typically 6+ months. NABSO types, blood-injection-injury fainting, exposure first.
Wernicke-Korsakoff Mnemonic: COA Triad & Thiamine First
Hotel B1 memory palace: Wernicke's COA triad (confusion, ophthalmoplegia, ataxia), Korsakoff amnesia and confabulation, mammillary bodies, thiamine first.
Pulmonary3 posts
Pulmonology practice questionsChurg-Strauss (EGPA) Mnemonic, Criteria & Treatment
A-E-G-P-A: adult asthma, eosinophilia, granulomas, peripheral neuropathy/purpura, ANCA in only 30-40% (MPO). 2022 ACR/EULAR points, GPA vs MPA, treatment.
Lung Volumes & Capacities: Mnemonic, Formulas, Normal Values
4 volumes (IRV, TV, ERV, RV) build 4 capacities (IC, FRC, VC, TLC). Spirometry can't measure RV, FRC or TLC; use helium, N2 washout or plethysmography.
Viral Pneumonia Mnemonic: Causes, Clues & Antivirals
VIP MARCH mnemonic for viral pneumonia: influenza, RSV, hMPV, adenovirus, SARS-CoV-2, CMV and hantavirus, plus post-flu bacterial pneumonia and oseltamivir.
Renal6 posts
Nephrology practice questionsAcronym trick for ADH and water balance
Quick mnemonic for ADH and water balance with high-yield USMLE facts on aquaporins, DI vs SIADH, and urine/serum osmolarity patterns.
CKD Stages by GFR Mnemonic: 90-60-45-30-15 Countdown
G1 ≥90, G2 60-89, G3a 45-59, G3b 30-44, G4 15-29, G5 <15 mL/min. Plus albuminuria A1-A3, CKD vs AKI clues, and which complications appear at each stage.
Dialysis Indications: AEIOU Mnemonic and Exam Clues
AEIOU: refractory Acidosis, Electrolytes (hyperkalemia with ECG changes), Intoxications, Overload, symptomatic Uremia. Why creatinine alone isn't one.
Polycystic Kidney Disease Mnemonic: ADPKD vs ARPKD
Adult = AD: PKD1/PKD2, hypertension, liver cysts, berry aneurysms. Baby = AR: PKHD1, oligohydramnios, pulmonary hypoplasia, congenital hepatic fibrosis.
Renal Tubular Acidosis Types 1, 2, 4: Chart & Mnemonic
RTA type 1: urine pH >5.5, low K+, calcium phosphate stones. Type 2: HCO3- wasting, Fanconi, low K+. Type 4: low aldosterone, high K+. Chart and traps.
Thiazide Diuretics Mnemonic: HyperGLUC, NCC & Calcium Stones
Thiazides block NCC in the early DCT. HyperGLUC: high glucose, lipids, uric acid, calcium; low K, Mg, Na; alkalosis. Uses: BP, Ca stones, nephrogenic DI.
Reproductive3 posts
Obstetrics & Gynecology practice questionsEctopic Pregnancy Mnemonic: ECTOPIC, hCG & Methotrexate
ECTOPIC: Early pain/bleeding, Cervical motion tenderness, Tubal, hCG Out of step with TVUS, Predisposing risks, Imaging, Care: methotrexate vs surgery.
Hypospadias vs Epispadias Mnemonic: Ventral vs Dorsal
Hypo = under: ventral meatus, dorsal hood, ventral chordee, don't circumcise. Epi = on top: dorsal meatus, bladder exstrophy, incontinence. DSD red flags.
Ovarian Tumors Mnemonic: Memory Palace, Markers & Histology
Ovarian tumor memory palace: serous (psammoma), mucinous, Brenner; dermoid, dysgerminoma (LDH), yolk sac (AFP); granulosa (inhibin), Krukenberg.
Frequently Asked Questions
Do mnemonics work for USMLE Step 1?
Yes, for the narrow job of recalling lists, sequences, and look-alike names under time pressure. They do not replace understanding a mechanism, and they only hold if you rehearse the letter-to-fact links at spaced intervals rather than rereading the phrase.
How many mnemonics should I memorize for Step 1?
Fewer than you think. Keep the ones for facts that have no logic to reconstruct, drop any you can derive from a mechanism, and retire each one once you can recall the list without the cue. A short set you can actually use beats a long set you half-remember.
Are these mnemonics also useful for Step 2 CK?
Many are. The microbiology, cardiovascular, renal, and pharmacology entries cover facts that reappear in Step 2 CK vignettes. Step 2 questions weight management decisions over recall, so pair a mnemonic with practice questions rather than relying on it alone.
Why does a mnemonic I know still fail me on a question?
Usually because the question tests one item in the list at the level of mechanism, or because two mnemonics share a letter and the wrong fact surfaced. Both are fixed the same way: answer questions on that topic and let the misses show you which link is weak.
Sources
- Post counts and the per-system listing come from the StepGenie blog database and refresh once a day.
- The four featured posts are an editorial pick made in September 2026, one from each of four systems. They are not ranked by traffic, search volume, or any other measurement.
- Spacing effect: Cepeda NJ, Pashler H, Vul E, Wixted JT, Rohrer D. Distributed practice in verbal recall tasks: a review and quantitative synthesis. Psychological Bulletin. 2006;132(3):354–380.
- Testing effect: Roediger HL, Karpicke JD. Test-enhanced learning: taking memory tests improves long-term retention. Psychological Science. 2006;17(3):249–255.
Find out which of these you can actually use
A mnemonic tells you the list; a question tells you whether you can apply it. StepGenie tags every missed question by system, so the mnemonics worth another pass are the ones your own attempts point to.