Medicine
What is hypothyroidism?
1) Clear the area of dangerous objects. 2) Cushion their head. 3) Do NOT put anything in their mouth or restrain them. 4) Turn them onto their side after the seizure stops (recovery position). 5) Call emergency services if the seizure lasts more than 5 minutes, they don't regain consciousness, or it's their first seizure.
Accumulation of excess fat in liver cells. Non-alcoholic fatty liver disease (NAFLD) is linked to obesity, diabetes, and metabolic syndrome. Can progress to inflammation (NASH), fibrosis, and cirrhosis. Often asymptomatic. Managed with weight loss, exercise, and controlling metabolic risk factors.
A condition where the thyroid gland doesn't produce enough thyroid hormones, leading to fatigue, weight gain, cold sensitivity, dry skin, constipation, and depression. Most commonly caused by Hashimoto's disease (autoimmune). Treated with daily synthetic thyroid hormone (levothyroxine).
Ligaments connect bone to bone and stabilize joints (e.g., ACL in the knee). Tendons connect muscle to bone and transmit force for movement (e.g., Achilles tendon). Both are made of connective tissue but serve different functions. Injuries: ligament sprains, tendon strains/tendinitis.
Medicine
What is HIPAA?
Health Insurance Portability and Accountability Act (1996). Key provisions: Privacy Rule protects patient health information (PHI) from unauthorized disclosure. Security Rule requires safeguards for electronic PHI. Covered entities: healthcare providers, health plans, clearinghouses. Patients have rights to access their records. Violations: civil fines up to $1.5 million/year, criminal penalties for knowing violations. Allows disclosures for treatment, payment, operations.
A group of genetic diseases causing progressive weakness and loss of muscle mass. Duchenne muscular dystrophy (most common in children) is caused by a defect in the dystrophin gene. Symptoms begin in early childhood with difficulty walking. No cure; treatment includes physical therapy, corticosteroids, and supportive care.
When one drug affects the activity of another. Types: pharmacokinetic (affects absorption, distribution, metabolism, or excretion — e.g., rifampin induces CYP450 reducing oral contraceptive levels) and pharmacodynamic (drugs with additive, synergistic, or antagonistic effects at the target — e.g., combining two sedatives increases CNS depression). Some interactions are intentional (e.g., carbidopa + levodopa). Always check for interactions when prescribing.
Infection of the middle ear space behind the tympanic membrane. Most common in children 6-24 months due to shorter, more horizontal Eustachian tubes. Causes: S. pneumoniae, H. influenzae, Moraxella. Symptoms: ear pain, fever, irritability, bulging TM. Treatment: amoxicillin first-line. Watchful waiting appropriate for mild cases in children >2 years. Recurrent: consider tympanostomy tubes.
Medicine
What is ARDS (acute respiratory distress syndrome)?
Benign smooth muscle tumors of the uterus, extremely common (up to 80% of women by age 50). More prevalent in Black women. Symptoms depend on size/location: heavy menstrual bleeding, pelvic pressure, urinary frequency, constipation. Most are asymptomatic. Treatment: observation, hormonal therapy, uterine artery embolization, myomectomy, or hysterectomy for severe cases.
A life-threatening condition where fluid fills the alveoli, preventing adequate oxygen exchange. Causes: severe pneumonia, sepsis, trauma, aspiration. Symptoms: severe shortness of breath, rapid breathing, low oxygen. Requires ICU care with mechanical ventilation.
A recommended timeline for receiving vaccines at specific ages for optimal immune protection. Timing is based on when maternal antibodies wane, when children are most vulnerable to specific diseases, and when the immune system responds best. Delays can leave gaps in protection during critical periods.
The heart pumps blood through two loops: pulmonary circulation (heart → lungs → heart) picks up oxygen, and systemic circulation (heart → body → heart) delivers oxygen and nutrients to tissues. An adult's blood circulates the entire body in about 60 seconds.
Medicine
What is Henoch-Schönlein purpura (IgA vasculitis)?
A sensation that you or your surroundings are spinning or moving. Peripheral vertigo (inner ear problem) is most common, including BPPV (benign paroxysmal positional vertigo) and Meniere's disease. Central vertigo involves the brain. Symptoms: dizziness, nausea, balance problems. Treatment depends on the cause.
A group of genetic diseases causing progressive weakness and loss of muscle mass. Duchenne muscular dystrophy (most common in children) is caused by a defect in the dystrophin gene. Symptoms begin in early childhood with difficulty walking. No cure; treatment includes physical therapy, corticosteroids, and supportive care.
A chronic bone disorder where bone is broken down and rebuilt abnormally, resulting in enlarged, deformed, and weakened bones. Usually affects pelvis, skull, spine, and legs. Often asymptomatic; may cause bone pain, deformities, fractures, and hearing loss. Diagnosed by elevated alkaline phosphatase and bone scan. Treated with bisphosphonates.
The most common vasculitis in children, caused by IgA immune complex deposition. Classic tetrad: palpable purpura (legs and buttocks), arthritis/arthralgias, abdominal pain (colicky, may cause intussusception), and renal involvement (hematuria, proteinuria). Usually follows upper respiratory infection. Self-limiting in most cases (weeks to months). Monitor renal function long-term.
Medicine
What is pheochromocytoma?
An abnormal bulge in the wall of the aorta (the body's largest artery). Can occur in the abdomen (AAA) or chest (thoracic). Often asymptomatic until rupture, which is life-threatening. Risk factors: smoking, hypertension, age, family history. Large aneurysms may require surgical repair.
An inflammatory skin reaction caused by direct contact with an irritant or allergen. Irritant type: caused by chemicals, soaps, solvents (not immune-mediated). Allergic type: delayed hypersensitivity reaction (e.g., poison ivy, nickel, latex). Symptoms: red, itchy, vesicular rash in the pattern of contact. Treatment: avoidance, topical steroids, cool compresses.
A rare catecholamine-secreting tumor of the adrenal medulla. Classic triad: episodic headache, sweating, and palpitations with severe hypertension. Rule of 10s: 10% bilateral, 10% extra-adrenal, 10% malignant, 10% familial (MEN 2, VHL). Diagnosed by elevated plasma or urine metanephrines. Treatment: alpha-blocker first (phenoxybenzamine), then beta-blocker, then surgical removal. Never give beta-blocker before alpha-blocker (risk of hypertensive crisis).
Medications (e.g., losartan, valsartan) that block the angiotensin II receptor, lowering blood pressure. Similar effects to ACE inhibitors but without the dry cough side effect. Used for hypertension, heart failure, and diabetic kidney disease.
Medicine
What is adrenal insufficiency (Addison's disease)?
The first-line oral medication for Type 2 diabetes. It lowers blood sugar by reducing glucose production in the liver and improving insulin sensitivity. Side effects: nausea, diarrhea, and rarely lactic acidosis. Does not cause weight gain.
The ratio between the toxic dose and the therapeutic dose (TD50/ED50). A narrow therapeutic index means a small difference between effective and toxic doses, requiring careful monitoring. Examples of narrow TI drugs: warfarin, lithium, digoxin, theophylline, phenytoin, aminoglycosides. Wide TI drugs (safer): penicillin, acetaminophen (at normal doses). Narrow TI drugs often need blood level monitoring.
Insufficient production of cortisol (and often aldosterone) by the adrenal glands. Primary: autoimmune destruction (most common in developed countries), infections (TB). Secondary: from chronic steroid use then abrupt withdrawal. Symptoms: fatigue, weight loss, hypotension, hyperpigmentation (primary only), salt craving, hypoglycemia. Adrenal crisis: life-threatening. Treatment: lifelong hydrocortisone replacement, stress dose steroids for illness.
An inherited blood disorder where red blood cells become crescent (sickle) shaped due to abnormal hemoglobin (HbS). Sickled cells block blood flow, causing pain crises, organ damage, anemia, and infections. Most common in people of African descent. Treatment: hydroxyurea, blood transfusions, pain management. Cure: stem cell transplant.
Medicine
What are the lobes of the brain and their functions?
An inflammatory condition causing muscle pain and stiffness in the shoulders, neck, and hips. Typically affects people over 50. Symptoms develop rapidly. ESR and CRP are usually very elevated. Responds dramatically to low-dose corticosteroids (prednisone). Associated with giant cell arteritis (temporal arteritis) in some patients.
Medications that reduce muscle spasms and tension. Centrally acting (cyclobenzaprine, baclofen) work on the brain/spinal cord. Used for acute back pain, muscle spasms, and spasticity. Side effects: drowsiness, dizziness, dry mouth.
A medical condition where use of alcohol or drugs leads to significant impairment, including health problems, disability, and failure to meet responsibilities. Characterized by craving, tolerance, withdrawal, and loss of control. Treatment: behavioral therapy, medications (methadone, naltrexone, buprenorphine for opioids), support groups.
Frontal lobe: executive function, personality, motor cortex, Broca's area (speech production). Parietal lobe: sensory processing, spatial awareness, proprioception. Temporal lobe: hearing, memory, Wernicke's area (language comprehension). Occipital lobe: visual processing. Cerebellum: coordination, balance, fine motor control. Brainstem: vital functions (breathing, heart rate, consciousness).
Medicine
What is the blood-brain barrier (BBB)?
A selective semipermeable barrier formed by tight junctions between brain capillary endothelial cells, supported by astrocyte foot processes. Prevents most blood-borne substances from entering the brain. Allows passage of: small lipophilic molecules, O2, CO2, glucose (via GLUT1 transporter). Blocks most bacteria, large molecules, and many drugs. Clinical significance: limits drug delivery to brain; disrupted in meningitis, stroke, and brain tumors.
A spectrum of conditions from unstable angina to myocardial infarction, all caused by reduced blood flow to the heart. Unstable angina: chest pain at rest, no troponin elevation. NSTEMI: troponin elevated, no ST elevation. STEMI: troponin elevated, ST elevation. Initial treatment (MONA is outdated): aspirin, nitroglycerin, heparin, morphine only if needed, dual antiplatelet therapy. Risk stratification guides further management.
Insertion of a tube (endotracheal tube) through the mouth or nose into the trachea to maintain an open airway or deliver mechanical ventilation. Used during general anesthesia, respiratory failure, cardiac arrest, and when the airway is at risk. Performed by anesthesiologists or emergency physicians.
12–20 breaths per minute at rest. A rate above 20 (tachypnea) may indicate respiratory distress, fever, or anxiety. A rate below 12 (bradypnea) may indicate central nervous system depression or certain medications.
Medicine
What is septic shock?
An inherited bleeding disorder caused by deficiency of clotting factors. Hemophilia A (80%): factor VIII deficiency. Hemophilia B (Christmas disease): factor IX deficiency. X-linked recessive (mostly males affected). Symptoms: easy bruising, prolonged bleeding, hemarthrosis (joint bleeding). Treated with factor replacement therapy. Severity depends on factor level.
The most severe form of sepsis, with dangerously low blood pressure that doesn't respond to fluid resuscitation. Mortality rate: 40-60%. Causes multi-organ failure. Treatment: vasopressors (norepinephrine), IV antibiotics, aggressive fluid resuscitation, and ICU monitoring. Every hour of delayed antibiotics increases mortality.
An inner ear disorder causing episodes of vertigo, tinnitus (ringing), hearing loss, and fullness in the ear. Episodes last minutes to hours. Cause: abnormal fluid buildup in the inner ear. Managed with low-sodium diet, diuretics, and anti-vertigo medications.
A scale ranking carbohydrate-containing foods by how quickly they raise blood sugar (0-100). High GI foods (>70): white bread, sugar, white rice. Low GI foods (<55): whole grains, legumes, most fruits, vegetables. Choosing low GI foods helps manage blood sugar, especially for diabetics.
Medicine
What is the WBC differential and what does each cell type indicate?
An essential mineral for heart function, muscle contraction, and nerve signaling. Helps counteract sodium's effect on blood pressure. Recommended: 2,600-3,400 mg/day. Sources: bananas, potatoes, spinach, beans, yogurt, salmon. Both too much and too little potassium can cause dangerous heart rhythm problems.
Medications that reduce the immune system's activity. Used to prevent organ transplant rejection (cyclosporine, tacrolimus), treat autoimmune diseases (methotrexate, azathioprine), and manage severe inflammation. Side effects: increased infection risk and reduced cancer surveillance.
Acute leukemia: rapid proliferation of immature cells (blasts) in bone marrow. Aggressive, requires immediate treatment. Types: ALL (most common childhood cancer), AML (most common adult acute leukemia). Chronic leukemia: slower proliferation of more mature cells. CLL: most common adult leukemia, often indolent. CML: associated with Philadelphia chromosome (BCR-ABL).
A breakdown of white blood cell types: Neutrophils (55-70%): bacterial infections. Lymphocytes (20-40%): viral infections, immune function. Monocytes (2-8%): chronic inflammation. Eosinophils (1-4%): allergies, parasites. Basophils (<1%): allergic reactions. Left shift (increased bands/immature neutrophils) suggests acute bacterial infection.
Medicine
What does benign vs malignant mean?
Benign: not cancerous; does not invade surrounding tissues or spread. Usually not life-threatening. Malignant: cancerous; can invade nearby tissues and metastasize (spread) to distant sites. Requires prompt treatment.
Endemic: a disease consistently present in a region (e.g., malaria in tropical areas). Epidemic: a sudden increase in cases beyond normal levels in a region. Pandemic: an epidemic that spreads across multiple countries or continents (e.g., COVID-19). These terms describe the spread pattern, not severity.
A pregnancy complication after 20 weeks characterized by new-onset hypertension (≥140/90) and proteinuria, or hypertension with end-organ dysfunction. Risk factors: first pregnancy, chronic hypertension, diabetes, multiple gestation. Can progress to eclampsia (seizures) or HELLP syndrome. Treatment: delivery is the only cure. Magnesium sulfate for seizure prevention. Monitor closely.
An ultrasound of the heart providing real-time images of cardiac structure and function. Measures: ejection fraction (normal ≥55%), valve function, wall motion abnormalities, chamber sizes, pericardial effusion. Types: transthoracic (TTE, standard), transesophageal (TEE, probe in esophagus for better views), stress echo (during exercise or dobutamine). Non-invasive, no radiation. The primary cardiac imaging tool.
Medicine
What is the Revised Trauma Score?
A physiological scoring system using three parameters: GCS (13-15=4, 9-12=3, 6-8=2, 4-5=1, 3=0), systolic BP (>89=4, 76-89=3, 50-75=2, 1-49=1, 0=0), and respiratory rate (10-29=4, >29=3, 6-9=2, 1-5=1, 0=0). Weighted formula determines triage priority. Score of 12 = normal. Used in field triage and trauma outcome prediction.
Injectable or oral diabetes medications (e.g., semaglutide, liraglutide, dulaglutide) that mimic the incretin hormone GLP-1. Effects: stimulate insulin release, suppress glucagon, slow gastric emptying, reduce appetite. Significant weight loss benefit. Also approved for obesity treatment. Side effects: nausea, vomiting.
A form of heart failure where fluid builds up around the heart and in the body. Left-sided CHF causes fluid in the lungs (pulmonary edema). Right-sided CHF causes fluid in the legs, abdomen, and liver. Symptoms: shortness of breath, swelling, weight gain, fatigue.
Inflammation of the pancreas. Acute pancreatitis causes sudden severe upper abdominal pain radiating to the back, nausea, vomiting. Common causes: gallstones and heavy alcohol use. Chronic pancreatitis leads to permanent damage. Treatment: IV fluids, pain management, fasting, and addressing the cause.
Medicine
What does tachy- mean in medical terms?
A condition where fatty deposits (plaque) build up inside artery walls, causing them to narrow and harden. This restricts blood flow and can lead to heart attack, stroke, or peripheral artery disease. Risk factors: high cholesterol, high BP, smoking, diabetes, obesity.
Disease or suffering. Examples: neuropathy (nerve disease), cardiomyopathy (heart muscle disease), retinopathy (retina disease), nephropathy (kidney disease), myopathy (muscle disease).
Fast or rapid. Examples: tachycardia (fast heart rate, above 100 bpm), tachypnea (fast breathing rate). Opposite of brady- (slow): bradycardia (slow heart rate), bradypnea (slow breathing).
An electrocardiogram records the electrical activity of the heart using electrodes placed on the skin. It shows heart rate, rhythm, and can detect heart attacks, arrhythmias, and other cardiac conditions. A standard ECG uses 12 leads and takes about 10 seconds.
Medicine
What is diabetic ketoacidosis (DKA)?
A common respiratory virus causing cold-like symptoms in most children. In infants, it can cause bronchiolitis and pneumonia, potentially requiring hospitalization. Symptoms: cough, wheezing, difficulty breathing, poor feeding. Preventive antibody (palivizumab) available for high-risk infants.
A life-threatening complication of type 1 diabetes (occasionally type 2). Occurs when insulin deficiency causes uncontrolled lipolysis → ketone production → metabolic acidosis. Triad: hyperglycemia (usually >250), metabolic acidosis (pH <7.3, HCO3 <18), and ketonemia/ketonuria. Symptoms: polyuria, polydipsia, abdominal pain, Kussmaul breathing, fruity breath. Treatment: IV fluids, insulin drip, potassium replacement.
A peripherally inserted central catheter — a long, thin catheter inserted through a peripheral vein (usually basilic or cephalic) and advanced until the tip reaches the superior vena cava near the heart. Uses: long-term IV antibiotics (weeks), TPN, chemotherapy, frequent blood draws. Advantages over central lines: lower insertion risk, bedside placement. Risks: thrombosis (DVT), infection (lower rate than central lines), malposition.
A type of anemia caused by the inability to absorb vitamin B12 due to lack of intrinsic factor (a protein made in the stomach). Results in large, immature red blood cells (megaloblastic anemia). Symptoms: fatigue, numbness/tingling, balance problems, confusion. Treated with B12 injections.
Medicine
What are the three types of muscle tissue?
Breakdown of skeletal muscle releasing intracellular contents (myoglobin, potassium, CK) into the bloodstream. Causes: crush injuries, extreme exercise, statins, seizures, drug abuse. Symptoms: muscle pain, weakness, dark tea-colored urine. Complications: AKI (myoglobin clogs renal tubules), hyperkalemia, DIC. Treatment: aggressive IV fluid resuscitation. CK level >5× normal.
Systolic pressure (top number) is the force when the heart contracts. Diastolic pressure (bottom number) is the force when the heart relaxes between beats. Elevated systolic is more common in older adults; elevated diastolic is more common in younger adults.
A chronic bone disorder where bone is broken down and rebuilt abnormally, resulting in enlarged, deformed, and weakened bones. Usually affects pelvis, skull, spine, and legs. Often asymptomatic; may cause bone pain, deformities, fractures, and hearing loss. Diagnosed by elevated alkaline phosphatase and bone scan. Treated with bisphosphonates.
Skeletal muscle (voluntary movement), cardiac muscle (heart contractions, involuntary), and smooth muscle (found in organs and blood vessels, involuntary). Each has a distinct structure suited to its function.
Medicine
What is sciatica?
In the alveoli (tiny air sacs in the lungs), oxygen diffuses from inhaled air into the blood, while carbon dioxide diffuses from the blood into the alveoli to be exhaled. This process is called gas exchange.
Pain radiating along the sciatic nerve from the lower back through the hip and down the leg. Usually caused by a herniated disc, bone spur, or spinal stenosis compressing the nerve. Symptoms: sharp pain, numbness, tingling in one leg. Most cases resolve in weeks with conservative treatment.
The spontaneous loss of a pregnancy before 20 weeks of gestation. Occurs in about 10-20% of known pregnancies. Most are caused by chromosomal abnormalities in the embryo. Symptoms: vaginal bleeding, cramping, tissue passage. Most women can have healthy pregnancies afterward.
Breakdown of muscle fibers releasing intracellular contents into bloodstream, caused by intense or unaccustomed exercise. Risk factors: heat, dehydration, sickle cell trait, NSAIDs, statins. Symptoms: severe muscle pain, weakness, dark (cola-colored) urine. Labs: CK >5× normal (often >10,000 U/L). Complications: AKI, hyperkalemia, DIC. Treatment: aggressive IV hydration (200-300 mL/hr).
Medicine
What is Lewy body dementia?
A cancer of blood-forming tissues (bone marrow), causing overproduction of abnormal white blood cells. Types: acute (rapid, ALL/AML) and chronic (slow, CLL/CML). Symptoms: fatigue, frequent infections, easy bruising/bleeding, weight loss. Treated with chemotherapy, targeted therapy, radiation, or stem cell transplant.
Proximal means closer to the center of the body (e.g., the shoulder is proximal to the elbow). Distal means farther from the center (e.g., the fingers are distal to the wrist). Used to describe anatomical locations.
The second most common type of progressive dementia after Alzheimer's. Features: visual hallucinations, fluctuating cognition, parkinsonian motor symptoms, REM sleep behavior disorder. Caused by Lewy body protein deposits in the brain. Patients are very sensitive to antipsychotic medications (can worsen symptoms severely).
Palliative care: specialized medical care focused on relief of symptoms, pain, and stress of serious illness. Can be provided alongside curative treatment at any stage. Hospice: a type of palliative care for patients with terminal illness (prognosis <6 months) who have decided to forgo curative treatment. Both focus on quality of life. Palliative care ≠ giving up.
Medicine
What is neutropenic fever?
Fever (≥38.3°C single reading or ≥38.0°C sustained for 1 hour) in a patient with absolute neutrophil count <500/μL, usually from chemotherapy. A medical emergency because the immune system cannot fight infection. Requires immediate blood cultures and empiric broad-spectrum antibiotics (piperacillin-tazobactam or cefepime) within 1 hour. Mortality is significant without prompt treatment.
Hard deposits of minerals and salts that form inside the kidneys. Types: calcium oxalate (most common), uric acid, struvite, cystine. Symptoms: severe flank pain (renal colic), blood in urine, nausea. Small stones may pass with fluids and pain management. Large stones may need lithotripsy or surgery.
Type 1 (5-10%): absolute insulin deficiency from autoimmune beta-cell destruction. Requires lifelong insulin (basal-bolus or pump). Carb counting essential. Risk of DKA. Type 2 (90-95%): insulin resistance ± relative deficiency. First-line: metformin + lifestyle. Add-ons: SGLT2 inhibitors, GLP-1 agonists (both have cardiovascular/renal benefits), DPP-4 inhibitors, sulfonylureas, insulin if needed. Monitor HbA1c every 3 months.
Bleeding between the skull and dura mater, usually from a torn middle meningeal artery due to temporal bone fracture. Classic presentation: brief loss of consciousness, lucid interval, then rapid deterioration. CT shows lens-shaped (biconvex) collection. A neurosurgical emergency requiring craniotomy for evacuation.
Medicine
What are diuretics?
A procedure where a needle is inserted into the lower spinal canal to collect cerebrospinal fluid (CSF) for analysis. Used to diagnose meningitis, encephalitis, multiple sclerosis, and subarachnoid hemorrhage. Can also measure CSF pressure. Common side effect: post-procedure headache.
Medications that increase urine production to reduce fluid in the body. Types: loop diuretics (furosemide), thiazides (hydrochlorothiazide), and potassium-sparing (spironolactone). Used for hypertension, heart failure, and edema. Side effects: electrolyte imbalances, dehydration.
A cluster of interconnected risk factors increasing cardiovascular disease and type 2 diabetes risk. Diagnosed with ≥3 of 5 criteria: waist circumference >40 inches (men) or >35 inches (women), triglycerides ≥150, HDL <40 (men) or <50 (women), BP ≥130/85, fasting glucose ≥100. Affects ~35% of US adults. Treatment: lifestyle modification (diet, exercise, weight loss) is primary. Medications for individual components.
The most common type of anemia, caused by insufficient iron to produce adequate hemoglobin. Causes: blood loss (heavy periods, GI bleeding), poor dietary intake, malabsorption. Symptoms: fatigue, weakness, pale skin, brittle nails, pica (craving non-food items). Treated with iron supplements and addressing the underlying cause.
Medicine
What does 'half-life' mean in pharmacology?
Unusual sounds heard through a stethoscope during heartbeats, caused by turbulent blood flow. Many are innocent (harmless), especially in children. Abnormal murmurs may indicate valve problems (stenosis or regurgitation). Diagnosed with echocardiography.
Right-sided heart failure caused by chronic lung disease. Chronic hypoxia causes pulmonary vasoconstriction and pulmonary hypertension, which increases the workload on the right ventricle. Causes: COPD (most common), pulmonary fibrosis, sleep apnea. Symptoms: peripheral edema, jugular vein distension, hepatomegaly. Treatment targets the underlying lung disease.
A research study testing new medical treatments, drugs, or devices on human volunteers. Phases: Phase I (safety, small group), Phase II (effectiveness, larger group), Phase III (large-scale comparison with standard treatment), Phase IV (post-market surveillance). Randomized controlled trials (RCTs) are the gold standard.
The time it takes for the concentration of a drug in the blood to decrease by half. A drug with a short half-life (e.g., 2 hours) must be taken more frequently than one with a long half-life (e.g., 24 hours). It takes about 5 half-lives to eliminate a drug.
Medicine
What is mononucleosis (mono)?
Diabetes medications (e.g., empagliflozin, dapagliflozin, canagliflozin) that block glucose reabsorption in the kidneys, causing excess glucose to be excreted in urine. Benefits beyond glucose control: cardiovascular protection, kidney protection, and modest weight loss. Risk: urinary tract and genital infections, rare ketoacidosis.
An infection usually caused by Epstein-Barr virus (EBV), common in teenagers and young adults. Symptoms: extreme fatigue, fever, sore throat, swollen lymph nodes, enlarged spleen. Spread through saliva ('kissing disease'). No specific treatment; resolves in 2-4 weeks with rest.
Medications (e.g., losartan, valsartan) that block the angiotensin II receptor, lowering blood pressure. Similar effects to ACE inhibitors but without the dry cough side effect. Used for hypertension, heart failure, and diabetic kidney disease.
Strategies to prevent kidney stones: drink 2-3 liters of water daily, reduce sodium intake, limit animal protein, eat adequate calcium (dietary, not supplements), reduce oxalate-rich foods (for calcium oxalate stones), and maintain a healthy weight. Specific dietary changes depend on stone type.
Medicine
What is a dislocated joint?
Vaccines introduce a harmless form of a pathogen (weakened, inactivated, or a piece of it) to stimulate the immune system to produce antibodies and memory cells. If the real pathogen is encountered later, the body can fight it off quickly.
A pregnancy complication where the placenta partially or completely covers the cervical opening. Causes painless vaginal bleeding in the second or third trimester. Risk factors: prior cesarean section, multiple pregnancies, older age. Delivery is typically by cesarean section.
When the bones in a joint are forced out of their normal alignment. Most commonly affects shoulders, fingers, and knees. Symptoms: visible deformity, severe pain, inability to move the joint, swelling. A medical emergency requiring closed reduction (manual repositioning) under sedation. X-ray before and after to check for fractures.
A laboratory test where blood is collected into special bottles and incubated to detect bacteria or fungi in the bloodstream (bacteremia/fungemia). Drawn before antibiotics are started, usually 2 sets from different sites. Positive results identify the organism and guide antibiotic selection. Takes 24-72 hours for results.
Medicine
What is procalcitonin?
A patient-centered counseling approach to strengthen motivation for behavior change. Key principles: Express empathy, Develop discrepancy (between current behavior and goals), Roll with resistance (avoid arguing), Support self-efficacy. Uses open-ended questions, affirmations, reflective listening, and summaries (OARS). Evidence-based for: substance abuse, medication adherence, diet/exercise changes, smoking cessation. Respects patient autonomy.
A condition where fatty deposits (plaque) build up inside artery walls, causing them to narrow and harden. This restricts blood flow and can lead to heart attack, stroke, or peripheral artery disease. Risk factors: high cholesterol, high BP, smoking, diabetes, obesity.
The most common type of anemia, caused by insufficient iron to produce adequate hemoglobin. Causes: blood loss (heavy periods, GI bleeding), poor dietary intake, malabsorption. Symptoms: fatigue, weakness, pale skin, brittle nails, pica (craving non-food items). Treated with iron supplements and addressing the underlying cause.
A blood biomarker that rises specifically in bacterial infections and sepsis (but not viral infections or autoimmune inflammation). Normal: <0.1 ng/mL. >0.5 ng/mL suggests bacterial infection. Used to guide antibiotic therapy: initiation and discontinuation. Helps differentiate bacterial from viral respiratory infections. Serial measurements help monitor treatment response. Reduces unnecessary antibiotic use.
Medicine
What is evidence-based medicine?
The practice of making clinical decisions based on the best available research evidence, combined with clinical expertise and patient preferences. Hierarchy of evidence: systematic reviews and meta-analyses (strongest), RCTs, cohort studies, case-control studies, case reports, expert opinion (weakest).
The presence of abnormal amounts of protein in the urine. Normal urine contains very little protein. Persistent proteinuria is an early sign of kidney damage, common in diabetes and hypertension. Detected by urine dipstick or albumin-to-creatinine ratio. ACE inhibitors can help reduce proteinuria and slow kidney damage.
A urological emergency where the testicle rotates on its spermatic cord, cutting off blood supply. Most common in adolescents. Symptoms: sudden severe testicular pain, swelling, absent cremasteric reflex, nausea. Requires surgical detorsion within 6 hours to save the testicle. Ultrasound shows decreased blood flow. Both testes are surgically fixed (orchiopexy) to prevent recurrence.
Stopping, standing still, or maintaining a constant state. Examples: homeostasis (stable internal environment), hemostasis (stopping bleeding), metastasis (cancer spread to distant sites).
Medicine
What is tumor lysis syndrome?
A metabolic emergency occurring when cancer cells are rapidly destroyed (usually after starting chemotherapy), releasing intracellular contents. Results in: hyperuricemia, hyperkalemia, hyperphosphatemia, and hypocalcemia. Can cause acute kidney injury, cardiac arrhythmias, and seizures. Prevention: aggressive IV hydration and allopurinol or rasburicase. Most common with high-tumor-burden hematologic malignancies.
A condition, disease, or abnormal state. Examples: cirrhosis (liver scarring), stenosis (narrowing), thrombosis (blood clot formation), osteoporosis (bone loss), fibrosis (scar tissue formation).
Therapeutic index is the ratio between the toxic dose and the effective dose. Narrow TI drugs (warfarin, lithium, digoxin, phenytoin) require careful dosing and monitoring because small dose changes can cause toxicity or ineffectiveness. Wide TI drugs (amoxicillin, ibuprofen) have a larger margin of safety.
Minimally invasive surgery using small incisions (5-12mm) through which a camera (laparoscope) and instruments are inserted. Abdomen is inflated with CO2 for visualization. Advantages: less pain, shorter hospital stay, faster recovery, smaller scars, fewer wound complications. Common procedures: cholecystectomy, appendectomy, hernia repair, bariatric surgery, hysterectomy. Some procedures converted to open if complications arise.
Medicine
What is amyotrophic lateral sclerosis (ALS)?
Red blood cells (erythrocytes) carry oxygen using hemoglobin and have no nucleus. White blood cells (leukocytes) are part of the immune system and fight infections. RBCs vastly outnumber WBCs (~700:1).
An assisted reproductive technology where eggs are retrieved from the ovaries, fertilized with sperm in a laboratory, and the resulting embryos are transferred to the uterus. Used for infertility due to blocked tubes, endometriosis, male factor, or unexplained causes. Success rates vary by age (20-40% per cycle).
A progressive neurodegenerative disease affecting both upper and lower motor neurons. Causes progressive muscle weakness, atrophy, fasciculations, spasticity, and eventually respiratory failure. Cognition is usually preserved. Average survival: 3-5 years from diagnosis. No cure. Treatment: riluzole (modest survival benefit), edaravone, symptomatic management. Also known as Lou Gehrig's disease.
A dangerous metabolic complication when severely malnourished patients begin eating again. Rapid insulin release shifts electrolytes (phosphorus, potassium, magnesium) into cells, causing dangerous deficiencies. Can cause heart failure, respiratory failure, seizures, and death. Prevention: start feeding slowly (10-20 kcal/kg/day), supplement phosphorus, potassium, magnesium, and thiamine before and during refeeding.
Medicine
What is a pheochromocytoma?
General guideline: about 2.7 liters (91 oz) for women and 3.7 liters (125 oz) for men from all sources (food and beverages). Needs increase with exercise, heat, illness, and pregnancy/breastfeeding. Urine color is a practical indicator: pale yellow suggests adequate hydration.
A rare tumor of the adrenal medulla that produces excess catecholamines (epinephrine, norepinephrine). Symptoms: episodic severe hypertension, headache, sweating, rapid heartbeat, anxiety. Diagnosed with 24-hour urine or plasma metanephrines. Treatment: surgical removal after alpha-blocker blood pressure control. 10% rule: 10% bilateral, 10% malignant, 10% extra-adrenal.
Inflammation of the brain, usually caused by viral infections (herpes simplex, enteroviruses, arboviruses). Symptoms: headache, fever, confusion, seizures, and neurological deficits. Can be life-threatening. Diagnosed with MRI and lumbar puncture. Treated with antiviral medications (acyclovir for HSV).
A kidney disorder caused by glomerular inflammation. Features: hematuria (cola-colored urine), mild proteinuria, hypertension, edema, and decreased GFR. Causes: post-streptococcal glomerulonephritis (children), IgA nephropathy (most common worldwide), lupus nephritis, ANCA-associated vasculitis. Urinalysis shows RBC casts. Treatment targets the underlying cause.
Medicine
What is drug half-life?
Injectable or oral diabetes medications (e.g., semaglutide, liraglutide, dulaglutide) that mimic the incretin hormone GLP-1. Effects: stimulate insulin release, suppress glucagon, slow gastric emptying, reduce appetite. Significant weight loss benefit. Also approved for obesity treatment. Side effects: nausea, vomiting.
The time required for the drug concentration in the body to decrease by 50%. Important for determining dosing frequency. Steady state is reached after ~4-5 half-lives. Short half-life drugs need more frequent dosing. Examples: ibuprofen (2 hours), metoprolol (3-7 hours), amoxicillin (1 hour), warfarin (40 hours), amiodarone (40-55 days). Renal or hepatic impairment may prolong half-life.
Endemic: a disease consistently present in a region (e.g., malaria in tropical areas). Epidemic: a sudden increase in cases beyond normal levels in a region. Pandemic: an epidemic that spreads across multiple countries or continents (e.g., COVID-19). These terms describe the spread pattern, not severity.
When one drug affects the activity of another. Types: pharmacokinetic (affects absorption, distribution, metabolism, or excretion — e.g., rifampin induces CYP450 reducing oral contraceptive levels) and pharmacodynamic (drugs with additive, synergistic, or antagonistic effects at the target — e.g., combining two sedatives increases CNS depression). Some interactions are intentional (e.g., carbidopa + levodopa). Always check for interactions when prescribing.
Medicine
What is anemia of chronic disease?
A small device implanted under the skin near the collarbone that sends electrical impulses to the heart to maintain a regular heartbeat. Used for bradycardia (slow heart rate) and certain arrhythmias. Battery lasts 5-15 years.
The second most common type of anemia, associated with chronic inflammation, infection, autoimmune disease, and cancer. Inflammatory cytokines increase hepcidin, which traps iron in storage (ferritin often elevated, but serum iron low). Normocytic, normochromic anemia. Treatment: address underlying disease. EPO may help in some cases.
A urological emergency where the testicle rotates on its spermatic cord, cutting off blood supply. Most common in adolescents. Symptoms: sudden severe testicular pain, swelling, absent cremasteric reflex, nausea. Requires surgical detorsion within 6 hours to save the testicle. Ultrasound shows decreased blood flow. Both testes are surgically fixed (orchiopexy) to prevent recurrence.
A vision development disorder where one eye does not achieve normal visual acuity despite corrective lenses. Usually develops in childhood. The brain favors one eye over the other. Treated early with patching the stronger eye, atropine drops, or corrective lenses. Best results when treated before age 7.
Medicine
What is normal blood pressure?
Normal blood pressure is below 120/80 mmHg. The top number (systolic) measures pressure when the heart beats; the bottom number (diastolic) measures pressure between beats. Elevated: 120–129/<80. High (Stage 1): 130–139/80–89. High (Stage 2): ≥140/≥90.
A chronic inflammatory arthritis primarily affecting the spine and sacroiliac joints. Causes progressive spinal stiffness and fusion (bamboo spine). Symptoms: chronic lower back pain and stiffness (worse in morning, improves with exercise), reduced spinal mobility. Associated with HLA-B27 gene. Treated with NSAIDs, physical therapy, and biologics (TNF inhibitors).
Health Insurance Portability and Accountability Act (1996). Key provisions: Privacy Rule protects patient health information (PHI) from unauthorized disclosure. Security Rule requires safeguards for electronic PHI. Covered entities: healthcare providers, health plans, clearinghouses. Patients have rights to access their records. Violations: civil fines up to $1.5 million/year, criminal penalties for knowing violations. Allows disclosures for treatment, payment, operations.
1) Clear the area of dangerous objects. 2) Cushion their head. 3) Do NOT put anything in their mouth or restrain them. 4) Turn them onto their side after the seizure stops (recovery position). 5) Call emergency services if the seizure lasts more than 5 minutes, they don't regain consciousness, or it's their first seizure.
Medicine
What is a deviated septum?
When the nasal septum (wall between nostrils) is significantly off-center, obstructing one or both nasal passages. Causes: congenital or from injury. Symptoms: difficulty breathing through one nostril, nosebleeds, facial pain, snoring. Severe cases treated with septoplasty.
A mechanical device that assists or replaces spontaneous breathing. Delivers pressurized air/oxygen to the lungs through an endotracheal tube or tracheostomy. Modes include volume-controlled, pressure-controlled, and pressure support. Settings adjusted for tidal volume, respiratory rate, FiO2, and PEEP. Used in ICU for respiratory failure.
A machine providing mechanical breathing support. Modes: Volume control: delivers set tidal volume. Pressure control: delivers to set pressure. Pressure support: augments patient-initiated breaths. SIMV: combination of mandatory and spontaneous breaths. Settings include: tidal volume (6-8 mL/kg ideal body weight), respiratory rate, FiO2 (fraction of inspired oxygen), PEEP (positive end-expiratory pressure). Goal: adequate gas exchange with minimal lung injury.
Misfolded proteins that cause fatal neurodegenerative diseases by converting normal brain proteins into abnormal forms. Prion diseases include Creutzfeldt-Jakob disease (CJD), mad cow disease (BSE), and kuru. They are not living organisms, cannot be killed by standard sterilization, and have no treatment.
Medicine
What is OCD (obsessive-compulsive disorder)?
Cancer of the cervix, almost always caused by persistent infection with high-risk HPV strains. Prevention: HPV vaccination (most effective) and regular Pap smears/HPV tests for early detection of precancerous changes. When caught early, it is highly treatable. Treatment: surgery, radiation, chemotherapy.
A mental health condition featuring persistent unwanted thoughts (obsessions) and repetitive behaviors (compulsions) performed to reduce anxiety. Examples: fear of contamination with excessive handwashing, need for symmetry with arranging rituals. Treated with CBT (exposure and response prevention) and SSRIs.
Non-steroidal anti-inflammatory drugs (ibuprofen, naproxen, ketorolac, celecoxib) inhibit cyclooxygenase (COX) enzymes, reducing prostaglandin production. Effects: anti-inflammatory, analgesic, antipyretic. Risks: GI bleeding and ulcers (COX-1 inhibition reduces protective mucus), renal impairment (reduce renal blood flow), cardiovascular events (especially COX-2 selective), platelet dysfunction. Use lowest effective dose for shortest duration.
Diabetes medications (e.g., empagliflozin, dapagliflozin, canagliflozin) that block glucose reabsorption in the kidneys, causing excess glucose to be excreted in urine. Benefits beyond glucose control: cardiovascular protection, kidney protection, and modest weight loss. Risk: urinary tract and genital infections, rare ketoacidosis.
Medicine
What is urinary incontinence?
Diabetes medications (e.g., empagliflozin, dapagliflozin, canagliflozin) that block glucose reabsorption in the kidneys, causing excess glucose to be excreted in urine. Benefits beyond glucose control: cardiovascular protection, kidney protection, and modest weight loss. Risk: urinary tract and genital infections, rare ketoacidosis.
Involuntary loss of urine. Types: stress incontinence (leakage with coughing, sneezing, exercise), urge incontinence (sudden intense urge), overflow incontinence (bladder doesn't empty fully), and functional incontinence (physical/mental barriers). Treatments: pelvic floor exercises (Kegels), medications, devices, or surgery.
A screening test where cells are collected from the cervix to detect precancerous or cancerous changes. Recommended every 3 years for women ages 21-65 (or every 5 years with HPV co-testing). Has significantly reduced cervical cancer deaths through early detection and treatment of abnormalities.
Twisting of a segment of bowel around its mesentery, causing obstruction and potentially cutting off blood supply (strangulation). Most common sites: sigmoid colon and cecum. Symptoms: sudden severe abdominal pain, distension, vomiting, constipation. A surgical emergency. Sigmoid volvulus may be initially decompressed endoscopically.
Medicine
What is rhabdomyolysis?
The ratio between the toxic dose and the therapeutic dose (TD50/ED50). A narrow therapeutic index means a small difference between effective and toxic doses, requiring careful monitoring. Examples of narrow TI drugs: warfarin, lithium, digoxin, theophylline, phenytoin, aminoglycosides. Wide TI drugs (safer): penicillin, acetaminophen (at normal doses). Narrow TI drugs often need blood level monitoring.
The most common inherited bleeding disorder, caused by deficiency or dysfunction of von Willebrand factor (a protein helping blood clot). Symptoms: easy bruising, frequent nosebleeds, heavy menstrual periods, prolonged bleeding after injury/surgery. Milder than hemophilia. Treated with desmopressin or factor replacement.
A scale ranking carbohydrate-containing foods by how quickly they raise blood sugar (0-100). High GI foods (>70): white bread, sugar, white rice. Low GI foods (<55): whole grains, legumes, most fruits, vegetables. Choosing low GI foods helps manage blood sugar, especially for diabetics.
A condition where damaged skeletal muscle breaks down rapidly, releasing myoglobin and other contents into the blood. Causes: severe injury, extreme exercise, drugs, infections. Myoglobin can damage the kidneys, potentially causing acute kidney failure. Symptoms: muscle pain, weakness, dark urine. Treatment: aggressive IV fluids.
Medicine
What is chronic kidney disease complications?
A simple non-invasive test for peripheral arterial disease. Ratio of systolic BP at the ankle to systolic BP at the arm. Normal: 1.0-1.3. Borderline: 0.91-0.99. PAD: ≤0.90. Severe: <0.40 (critical limb ischemia). >1.3 suggests calcified, non-compressible arteries (common in diabetes). Screening recommended for adults >65, or >50 with diabetes or smoking history.
A medical condition where use of alcohol or drugs leads to significant impairment, including health problems, disability, and failure to meet responsibilities. Characterized by craving, tolerance, withdrawal, and loss of control. Treatment: behavioral therapy, medications (methadone, naltrexone, buprenorphine for opioids), support groups.
A recommended timeline for receiving vaccines at specific ages for optimal immune protection. Timing is based on when maternal antibodies wane, when children are most vulnerable to specific diseases, and when the immune system responds best. Delays can leave gaps in protection during critical periods.
CKD affects multiple organ systems: Cardiovascular (leading cause of death in CKD, hypertension), Hematologic (anemia from decreased EPO), Bone (renal osteodystrophy from vitamin D deficiency and secondary hyperparathyroidism), Electrolyte (hyperkalemia, hyperphosphatemia, metabolic acidosis), Uremic symptoms (nausea, confusion, pericarditis, neuropathy). Management: ACE inhibitors, phosphate binders, EPO, vitamin D, dietary restrictions.
Medicine
What is a normal respiratory rate for adults?
An X-ray of the breast used to screen for breast cancer. Current guidelines vary: USPSTF recommends biennial screening at 40-74, ACS recommends annual starting at 45 (optional at 40). Findings classified by BI-RADS (0-6). 3D mammography (tomosynthesis) improves detection. Reduces breast cancer mortality by ~20-30%. Supplemental MRI recommended for high-risk women.
12–20 breaths per minute at rest. A rate above 20 (tachypnea) may indicate respiratory distress, fever, or anxiety. A rate below 12 (bradypnea) may indicate central nervous system depression or certain medications.
A sudden decrease in kidney function occurring over hours to days. Causes: dehydration, severe infection (sepsis), medications (NSAIDs, contrast dye), obstruction (kidney stones). Symptoms: reduced urine output, fluid retention, confusion. Often reversible with prompt treatment of the underlying cause.
A condition where the fibrous tissue (fascia) in the palm thickens and contracts, causing fingers (usually ring and little finger) to curl inward permanently. More common in men, Northern European descent, and those with diabetes or alcohol use. Treatment: observation for mild cases, needle aponeurotomy, enzyme injection, or surgery for severe cases.
Medicine
What is the pituitary gland?
A coordinated program promoting appropriate use of antimicrobials (antibiotics, antivirals, antifungals) to improve patient outcomes, reduce adverse effects, combat antimicrobial resistance, and decrease unnecessary costs. Strategies: prescribing only when needed, choosing the right drug/dose/duration, and de-escalation when possible.
A physiological scoring system using three parameters: GCS (13-15=4, 9-12=3, 6-8=2, 4-5=1, 3=0), systolic BP (>89=4, 76-89=3, 50-75=2, 1-49=1, 0=0), and respiratory rate (10-29=4, >29=3, 6-9=2, 1-5=1, 0=0). Weighted formula determines triage priority. Score of 12 = normal. Used in field triage and trauma outcome prediction.
A pea-sized gland at the base of the brain, often called the 'master gland' because it controls other endocrine glands. It produces growth hormone, TSH (thyroid), ACTH (adrenal), LH/FSH (reproductive), prolactin (breast milk), and ADH (water balance).
PPIs (omeprazole, pantoprazole, esomeprazole) irreversibly block the H+/K+ ATPase pump in gastric parietal cells, reducing acid secretion by ~90%. Indications: GERD, peptic ulcers, H. pylori eradication, Zollinger-Ellison syndrome. Take 30-60 min before meals. Long-term risks: C. difficile infection, hypomagnesemia, bone fractures, vitamin B12 deficiency, kidney disease. Deprescribe when possible.
Medicine
What is point-of-care testing?
A medical condition where use of alcohol or drugs leads to significant impairment, including health problems, disability, and failure to meet responsibilities. Characterized by craving, tolerance, withdrawal, and loss of control. Treatment: behavioral therapy, medications (methadone, naltrexone, buprenorphine for opioids), support groups.
The study of how genetic variations affect individual responses to drugs. Examples: CYP2D6 poor metabolizers process codeine poorly; HLA-B*5701 carriers risk severe reactions to abacavir; VKORC1 variants affect warfarin dosing. Enables personalized medicine with safer, more effective prescribing.
A vision development disorder where one eye does not achieve normal visual acuity despite corrective lenses. Usually develops in childhood. The brain favors one eye over the other. Treated early with patching the stronger eye, atropine drops, or corrective lenses. Best results when treated before age 7.
Diagnostic testing performed at or near the patient rather than in a central laboratory. Examples: glucometer, rapid strep test, pregnancy test, urinalysis dipstick, rapid flu/COVID test, i-STAT (blood gas, electrolytes), INR monitor. Advantages: faster results (minutes vs. hours), immediate treatment decisions. Limitations: may be less accurate than lab testing, quality control requirements, operator-dependent.
Medicine
What is tetanus?
A serious bacterial infection (Clostridium tetani) that produces a toxin affecting the nervous system, causing painful muscle stiffness and spasms ('lockjaw'). Bacteria enter through wounds. Prevented by vaccination (DTaP/Tdap, with boosters every 10 years). Treatment: antitoxin, antibiotics, muscle relaxants.
A disease of the heart muscle that makes it harder for the heart to pump blood. Types: dilated (enlarged heart), hypertrophic (thickened walls), and restrictive (stiff walls). Causes: genetic, infections, alcohol abuse, or unknown. Can lead to heart failure.
A dietary pattern based on traditional foods from Mediterranean countries. Emphasizes: fruits, vegetables, whole grains, legumes, nuts, olive oil (primary fat), fish, and moderate wine. Limits red meat, processed foods, and added sugars. Strong evidence for cardiovascular disease prevention, reduced stroke risk, improved cognitive function, and reduced cancer risk. One of the most studied healthy diets.
Age-related loss of skeletal muscle mass, strength, and function. Begins around age 30 and accelerates after 60. Contributes to frailty, falls, disability, and loss of independence. Prevention and treatment: resistance exercise (most effective), adequate protein intake (1.0-1.2 g/kg/day), and vitamin D.
Medicine
What is a lumbar puncture (spinal tap)?
A laboratory test where blood is collected into special bottles and incubated to detect bacteria or fungi in the bloodstream (bacteremia/fungemia). Drawn before antibiotics are started, usually 2 sets from different sites. Positive results identify the organism and guide antibiotic selection. Takes 24-72 hours for results.
Hepatitis A: fecal-oral (contaminated food/water), usually acute. Hepatitis B: blood/body fluids, can become chronic. Hepatitis C: blood-borne, often chronic (now curable with antivirals). Hepatitis D: only with B co-infection. Hepatitis E: fecal-oral, usually acute. Vaccines exist for A and B.
A progressive neurodegenerative disease that destroys motor neurons controlling voluntary muscles. Also known as Lou Gehrig's disease. Symptoms: muscle weakness, twitching, difficulty speaking and swallowing, eventually respiratory failure. No cure. Average survival: 3-5 years after diagnosis. Riluzole may slightly slow progression.
A procedure inserting a needle into the subarachnoid space (L3-L4 or L4-L5 interspace) to collect cerebrospinal fluid (CSF). Indications: diagnose meningitis, subarachnoid hemorrhage, MS, Guillain-Barré, measure opening pressure (normal 6-20 cmH2O). CSF analysis: cell count, protein, glucose, Gram stain, culture. Contraindications: increased ICP with mass effect (risk of herniation), coagulopathy, skin infection at site.
Medicine
What is a coagulation panel (PT/INR and PTT)?
A chronic functional GI disorder causing abdominal pain, bloating, and altered bowel habits (diarrhea, constipation, or both). No structural damage is present. Triggers include stress, certain foods, and hormonal changes. Managed with diet (low FODMAP), fiber, antispasmodics, and stress management.
Non-pharmacological strategies (HELP protocol): frequent reorientation, cognitive stimulation, early mobilization, sleep hygiene (minimize nighttime interruptions, reduce noise), adequate hydration and nutrition, vision and hearing aids, minimize use of restraints and catheters, avoid deliriogenic medications (anticholinergics, benzodiazepines). Can reduce delirium incidence by 30-40%.
A disease of the heart muscle that makes it harder for the heart to pump blood. Types: dilated (enlarged heart), hypertrophic (thickened walls), and restrictive (stiff walls). Causes: genetic, infections, alcohol abuse, or unknown. Can lead to heart failure.
Tests measuring blood clotting function. PT (prothrombin time): tests extrinsic pathway (factors VII, X, V, II, fibrinogen). INR standardizes PT for warfarin monitoring (therapeutic range 2-3). PTT (partial thromboplastin time): tests intrinsic pathway (factors XII, XI, IX, VIII). Elevated PT: warfarin, liver disease, vitamin K deficiency. Elevated PTT: heparin therapy, hemophilia, lupus anticoagulant.
Medicine
How do Type 1 and Type 2 diabetes medications differ?
Inflammation of the liver. Hepatitis A (fecal-oral route, usually resolves), Hepatitis B (blood/body fluids, can become chronic), and Hepatitis C (blood-borne, often chronic) are the most common types. Symptoms: jaundice, fatigue, abdominal pain, nausea. Vaccines exist for A and B.
Complex medications derived from living organisms (cells, proteins). Include: monoclonal antibodies (-mab: infliximab, adalimumab), fusion proteins (-cept: etanercept), recombinant proteins (insulin, EPO, growth hormone). Used for autoimmune diseases, cancer, and more. Given by injection or infusion (proteins would be digested orally). Expensive. Biosimilars are similar but not identical copies (like generics for biologics).
Type 1 diabetes requires insulin injections (the pancreas produces no insulin). Type 2 diabetes is initially treated with oral medications (metformin, sulfonylureas, SGLT2 inhibitors) and may eventually require insulin if the disease progresses.
A patient-centered counseling approach to strengthen motivation for behavior change. Key principles: Express empathy, Develop discrepancy (between current behavior and goals), Roll with resistance (avoid arguing), Support self-efficacy. Uses open-ended questions, affirmations, reflective listening, and summaries (OARS). Evidence-based for: substance abuse, medication adherence, diet/exercise changes, smoking cessation. Respects patient autonomy.
Medicine
What are cataracts?
Twisting of a segment of bowel around its mesentery, causing obstruction and potentially cutting off blood supply (strangulation). Most common sites: sigmoid colon and cecum. Symptoms: sudden severe abdominal pain, distension, vomiting, constipation. A surgical emergency. Sigmoid volvulus may be initially decompressed endoscopically.
The study of how genetic variations affect individual responses to drugs. Examples: CYP2D6 poor metabolizers process codeine poorly; HLA-B*5701 carriers risk severe reactions to abacavir; VKORC1 variants affect warfarin dosing. Enables personalized medicine with safer, more effective prescribing.
Clouding of the eye natural lens, causing blurry vision, faded colors, glare, and difficulty seeing at night. Most common cause of vision loss in people over 40. Risk factors: aging, diabetes, UV exposure, smoking. Treatment: surgical lens replacement (one of the most common surgeries).
Maslow's theory prioritizes human needs in order: 1) Physiological (air, water, food, sleep, warmth), 2) Safety (shelter, health, stability), 3) Love/belonging (relationships, community), 4) Esteem (achievement, respect), 5) Self-actualization. In healthcare: address basic physiological needs first (pain, breathing, nutrition), then safety (fall prevention, infection control), before higher-level needs (education, emotional support, rehabilitation goals).
Medicine
What does -emia mean in medical terms?
When the nasal septum (wall between nostrils) is significantly off-center, obstructing one or both nasal passages. Causes: congenital or from injury. Symptoms: difficulty breathing through one nostril, nosebleeds, facial pain, snoring. Severe cases treated with septoplasty.
Folate is crucial for proper neural tube development in the fetus during the first weeks of pregnancy. Deficiency can cause neural tube defects (spina bifida, anencephaly). Women of childbearing age should consume 400-800 mcg daily. Sources: leafy greens, fortified grains, legumes. Folic acid is the synthetic form.
A research study testing new treatments in human volunteers. Phases: Phase 1 (safety, dosing, small group), Phase 2 (efficacy, side effects, larger group), Phase 3 (confirms efficacy, compares to standard treatment, large population, required for FDA approval), Phase 4 (post-market surveillance). Requires informed consent, IRB approval, and adherence to Good Clinical Practice. Results registered at ClinicalTrials.gov.
A blood condition. Examples: anemia (low red blood cells/hemoglobin), septicemia (blood infection), hyperglycemia (high blood sugar), hypoxemia (low blood oxygen), leukemia (blood cancer).
Medicine
What is a chest tube (tube thoracostomy)?
A tube inserted into the pleural space to drain air (pneumothorax), blood (hemothorax), fluid (pleural effusion), or pus (empyema). Inserted through the 4th-5th intercostal space in the midaxillary line. Connected to a drainage system with water seal and suction. Monitor output volume and air leak. Removal when drainage <200 mL/day and no air leak, with follow-up chest X-ray.
End-stage chronic liver disease with irreversible fibrosis and nodular regeneration. Causes: alcohol, hepatitis B/C, NAFLD/NASH, autoimmune hepatitis. Compensated: may be asymptomatic. Decompensated: ascites, variceal bleeding, hepatic encephalopathy, jaundice, coagulopathy. Diagnosis: clinical + labs + imaging or biopsy. Child-Pugh and MELD scores assess severity. Treatment: address cause, manage complications. Liver transplant for end-stage.
A chronic condition characterized by widespread musculoskeletal pain, fatigue, sleep disturbances, and cognitive difficulties ('fibro fog'). The cause is unknown but involves abnormal pain processing. Diagnosis is clinical (no specific test). Managed with exercise, medications (duloxetine, pregabalin), therapy, and stress reduction.
An arterial blood gas test measures oxygen, carbon dioxide, and pH levels in arterial blood. Used to assess lung function, acid-base balance, and oxygenation. Normal values: pH 7.35-7.45, PaO2 80-100 mmHg, PaCO2 35-45 mmHg. Critical for managing respiratory failure and metabolic disorders.
Medicine
What is gastroenteritis?
Compression of the median nerve as it passes through the carpal tunnel in the wrist. Symptoms: numbness, tingling, and weakness in the thumb, index, and middle fingers. Causes: repetitive hand motions, pregnancy, thyroid disease. Treated with wrist splints, corticosteroid injections, or surgery.
A life-threatening complication of type 1 diabetes (occasionally type 2). Occurs when insulin deficiency causes uncontrolled lipolysis → ketone production → metabolic acidosis. Triad: hyperglycemia (usually >250), metabolic acidosis (pH <7.3, HCO3 <18), and ketonemia/ketonuria. Symptoms: polyuria, polydipsia, abdominal pain, Kussmaul breathing, fruity breath. Treatment: IV fluids, insulin drip, potassium replacement.
Inflammation of the stomach and intestines, usually caused by viral (norovirus, rotavirus) or bacterial (Salmonella, E. coli) infection. Symptoms: diarrhea, vomiting, stomach cramps, fever. Usually resolves in 1-3 days. Treatment: oral rehydration, rest. Seek help if severe dehydration occurs.
The study of how genetic variations affect individual responses to drugs. Examples: CYP2D6 poor metabolizers process codeine poorly; HLA-B*5701 carriers risk severe reactions to abacavir; VKORC1 variants affect warfarin dosing. Enables personalized medicine with safer, more effective prescribing.
Medicine
What are muscle relaxants?
A machine providing mechanical breathing support. Modes: Volume control: delivers set tidal volume. Pressure control: delivers to set pressure. Pressure support: augments patient-initiated breaths. SIMV: combination of mandatory and spontaneous breaths. Settings include: tidal volume (6-8 mL/kg ideal body weight), respiratory rate, FiO2 (fraction of inspired oxygen), PEEP (positive end-expiratory pressure). Goal: adequate gas exchange with minimal lung injury.
The study of how genetic variations affect individual responses to drugs. Examples: CYP2D6 poor metabolizers process codeine poorly; HLA-B*5701 carriers risk severe reactions to abacavir; VKORC1 variants affect warfarin dosing. Enables personalized medicine with safer, more effective prescribing.
Chronic inflammatory GI conditions. Crohn's disease: can affect any part of GI tract (mouth to anus), transmural inflammation, skip lesions, granulomas, fistulas, strictures. Ulcerative colitis: limited to colon, starts at rectum and extends proximally, continuous inflammation, superficial (mucosa/submucosa). Both: bloody diarrhea, abdominal pain, weight loss. Treatment: 5-ASA, steroids, immunomodulators, biologics (anti-TNF).
Medications that reduce muscle spasms and tension. Centrally acting (cyclobenzaprine, baclofen) work on the brain/spinal cord. Used for acute back pain, muscle spasms, and spasticity. Side effects: drowsiness, dizziness, dry mouth.
Medicine
What is a normal white blood cell (WBC) count?
A life-threatening complication of type 1 diabetes (occasionally type 2). Occurs when insulin deficiency causes uncontrolled lipolysis → ketone production → metabolic acidosis. Triad: hyperglycemia (usually >250), metabolic acidosis (pH <7.3, HCO3 <18), and ketonemia/ketonuria. Symptoms: polyuria, polydipsia, abdominal pain, Kussmaul breathing, fruity breath. Treatment: IV fluids, insulin drip, potassium replacement.
4,500–11,000 cells per microliter of blood. A high count (leukocytosis) may indicate infection, inflammation, or immune disorders. A low count (leukopenia) may indicate bone marrow problems, autoimmune conditions, or effects of certain medications.
Inflammation or infection of the sinuses (air-filled cavities around the nose). Symptoms: facial pain/pressure, nasal congestion, thick nasal discharge, headache. Acute sinusitis is usually viral and resolves in 7-10 days. Bacterial sinusitis may need antibiotics. Chronic sinusitis lasts 12+ weeks.
Ischemic heart disease, stroke, chronic obstructive pulmonary disease, lower respiratory infections, neonatal conditions, lung cancer, Alzheimer's disease, diarrheal diseases, diabetes mellitus, and kidney disease. The pattern varies between high-income and low-income countries.
Medicine
What is perioperative care?
Inflammation or infection of the sinuses (air-filled cavities around the nose). Symptoms: facial pain/pressure, nasal congestion, thick nasal discharge, headache. Acute sinusitis is usually viral and resolves in 7-10 days. Bacterial sinusitis may need antibiotics. Chronic sinusitis lasts 12+ weeks.
A chronic autoimmune disease where the immune system attacks multiple organs (skin, joints, kidneys, brain, heart). Characteristic butterfly-shaped facial rash. Symptoms: fatigue, joint pain, fever, skin rashes, kidney problems. More common in women. Treated with immunosuppressants.
Generic drugs contain the same active ingredient, dosage, and form as brand-name drugs but are sold under their chemical name at lower cost. They must meet the same regulatory standards for safety and effectiveness. Inactive ingredients may differ.
Medical care surrounding a surgical procedure. Preoperative: history, physical exam, risk assessment (cardiac, pulmonary), medication management (hold anticoagulants, continue beta-blockers), NPO guidelines (clear liquids 2h, light meal 6h, full meal 8h before anesthesia), informed consent. Intraoperative: anesthesia, monitoring, surgical site marking. Postoperative: pain management, DVT prophylaxis, early ambulation, wound care, monitoring for complications.