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Peripheral nerves Peripheral nerves lie outside the brain and spinal cord, carrying signals between the central nervous system and the rest of the body for movement, sensation and automatic functions.Editorially complete
Small intestine The longest part of the digestive system, linking the stomach to the large intestine; most digestion happens here and most nutrients are absorbed.Editorially complete
Large intestine The last part of the digestive tract: a long hollow tube that absorbs water from what is left of food, turns waste into stool and stores it until a bowel movement.Editorially complete
Blood vessels A network of tubes carrying blood between the heart and the body: arteries carry it away from the heart, veins bring it back, and tiny capillaries exchange materials with tissues.Editorially complete
Pancreas A long gland behind the stomach with two jobs: it makes juices that digest food, and hormones such as insulin that regulate blood glucose.Editorially complete
Brain The body's control centre inside the skull: thinking, memory, speech, movement and sensation, plus breathing and heartbeat control.Editorially complete
Lungs Two spongy organs in the chest that bring oxygen into the blood and remove carbon dioxide with every breath.Editorially complete
Spleen A roughly fist-sized organ in the upper left abdomen behind the ribs that filters the blood, helps fight infection and clears out old red blood cells.Editorially complete
Thyroid gland A small butterfly-shaped gland at the front of the neck that makes hormones controlling how the body uses energy, so it affects nearly every organ.Editorially complete
Trachea The main airway: a tube that carries oxygen-rich air from the voice box to the lungs and carries carbon dioxide out, before dividing into two bronchi that enter the lungs.Editorially complete
Heart A hollow muscular organ in the chest that pumps blood to the lungs for oxygen and then to the rest of the body.Editorially complete
Liver A large organ in the upper right abdomen that makes bile for fat digestion and stores and delivers nutrients.Editorially complete
Kidneys Two fist-sized organs below the rib cage on either side of the spine that filter blood and remove wastes and extra water as urine.Editorially complete
Bladder A hollow, muscular, balloon-shaped organ in the pelvis that stores urine from the kidneys and then empties it through the urethra.Editorially complete
Gallbladder A small pear-shaped organ below the liver in the upper right abdomen that stores bile and releases it into the intestine when you eat, to help digest fats.Editorially complete
Oesophagus A muscular tube that carries food from the throat to the stomach, running behind the windpipe and through an opening in the diaphragm.Editorially complete
Stomach An organ in the upper abdomen between the oesophagus and the small intestine that stores swallowed food, mixes it with acid and enzymes, and starts the digestion of protein.Editorially complete
Ear Captures and amplifies sound via the eardrum and ossicles; inner-ear cells turn it into nerve signals.Overview
Skin The body's outer cover: a barrier against germs and water loss, a temperature regulator, and home to touch receptors.Overview
Urinary system Filters blood, removes wastes and extra water as urine, and keeps fluids and salts in balance.Overview
Reproductive system Produces sex cells and hormones and makes fertilisation and pregnancy possible.Overview
Respiratory system Brings oxygen into the blood and removes carbon dioxide through gas exchange in the lungs.Overview
Circulatory system Carries oxygen- and nutrient-rich blood to all tissues and returns carbon dioxide and wastes.Overview
Nervous system The body's communication and control network: it senses, processes and sends commands to muscles and glands.Overview
Muscular system Produces movement, maintains posture, stabilises joints and generates body heat.Overview
Lymphatic system Returns excess tissue fluid to the blood, absorbs fats from the gut and takes part in immunity.Overview
Immune system Defends against germs, foreign substances and abnormal cells, and remembers some past encounters.Overview
Digestive system Breaks food into nutrients the blood can absorb and removes what is not digested.Overview
Blood A fluid tissue: red cells carry oxygen, white cells defend, platelets help clotting, all suspended in plasma.Overview
Eye The cornea and lens focus light on the retina, which turns it into signals the optic nerve sends to the brain.Overview
Endocrine system Glands releasing hormones into the blood to regulate growth, metabolism and reproduction.Overview
Joints Where bones meet: some are fixed (skull), some slightly movable, some freely movable (knee, shoulder).Overview
Skeletal system Supports the body, protects organs, enables movement with muscles, stores minerals and makes blood in the marrow.Overview
Heart valve disease Heart valve disease means a problem with one or more of the heart's four valves that keep blood flowing the right way: a valve may be too narrow or may leak. It ranges from no symptoms to needing treatment.Editorially complete
Gastroesophageal reflux disease A chronic condition in which stomach contents repeatedly flow back into the oesophagus, causing heartburn, regurgitation and other bothersome symptoms that can lead to complications. It often improves with lifestyle changes and medicines, and sometimes surgery.Editorially complete
High blood cholesterol (hyperlipidemia) Too much cholesterol (and sometimes triglycerides) in the blood. It usually causes no symptoms, but over time it builds up in artery walls and raises the risk of heart attack and stroke. It is found by a blood test and managed with lifestyle changes and sometimes medicines chosen by a doctor.Editorially complete
Hypertension (High blood pressure) A long-term condition in which the pressure in the blood vessels is too high. It usually causes no symptoms, yet raises the risk of heart disease, stroke and kidney disease. It is found by measuring blood pressure and managed with lifestyle and medicines.Editorially complete
Pulmonary hypertension A condition in which blood pressure in the blood vessels of the lungs is higher than normal, so the heart has to work harder to pump blood into the lungs. Symptoms include shortness of breath, tiredness, chest pain and dizziness. It has many causes, most often heart and lung diseases. Often there is no cure, but treatment can help manage the symptoms.Editorially complete
Arrhythmias An arrhythmia is a problem with the speed or regularity of the heartbeat: it may beat too fast, too slow or unevenly. Many need no treatment, but some need emergency care.Editorially complete
Diabetic neuropathy Long-term high blood sugar can damage nerves, causing numbness, tingling or pain in the feet and hands, and sometimes affecting internal organs such as the heart, bladder and digestion.Editorially complete
Diabetic retinopathy Long-term high blood sugar damages the blood vessels in the retina. There are usually no symptoms early on, so it is found by regular eye exams before it threatens sight.Editorially complete
Atopic dermatitis (eczema) A chronic skin disease that causes inflamed, dry and sometimes intensely itchy skin. It is not contagious, flares and settles over time, often starts in childhood, and is managed with skin care, moisturisers and medicines chosen with a doctor.Editorially complete
Influenza (flu) A contagious viral respiratory infection that starts suddenly with fever, cough, body aches and tiredness. Most people recover within days without specific treatment, but it can be severe in older adults, young children, pregnant women and people with chronic illness. An annual vaccine is the best protection.Editorially complete
Depression Depression is a real and common medical condition, not weakness and not just passing sadness. It affects mood, thinking, sleep, eating and work. It is treatable with talk therapy, medicines or both, and seeking help early is useful.Editorially complete
Pneumonia An acute lung infection in which the air sacs fill with fluid and pus, making breathing difficult. It is usually caused by bacteria or viruses and most people recover with appropriate care.Editorially complete
Cystic fibrosis A rare inherited disease that makes mucus in the lungs and digestive system thick and sticky, causing breathing and digestive problems. There is no cure yet, but modern treatments have greatly improved symptoms and life expectancy.Editorially complete
Allergic rhinitis (hay fever) A group of nose symptoms that occur when you breathe in allergens such as tree and grass pollen, dust or animal dander. They include sneezing, runny or blocked nose and itchy nose and eyes, and several medicines are available, chosen with a clinician or pharmacist.Editorially complete
Pancreatitis Pancreatitis is inflammation of the pancreas. The acute form causes sudden severe upper-abdominal pain and usually needs hospital care; the chronic form is long-term and gradually damages the pancreas.Editorially complete
Sinusitis Inflammation of the sinuses, the air-filled spaces in the skull bones around the nose. It often follows a cold and causes a blocked nose, facial pain or pressure and headache. Most cases improve on their own without antibiotics.Editorially complete
Viral hepatitis Viral hepatitis is an infection that inflames and damages the liver. Several viruses (A, B, C, D, E) cause it and they differ in how they spread and whether they become chronic.Editorially complete
Urinary tract infection A bacterial infection of part of the urinary system, most often the bladder, sometimes reaching the kidneys. Symptoms include burning or pain when urinating, frequent urination, and cloudy or bloody urine. It is diagnosed with a urine test and usually treated with antibiotics prescribed by a doctor.Editorially complete
Rheumatoid arthritis A chronic autoimmune disease in which the immune system attacks the body's own tissues, mostly the joints, causing pain, swelling and stiffness, and sometimes affecting other organs. There is no cure, but early treatment slows its progress, aiming for remission or near remission.Editorially complete
Dementia A syndrome that impairs memory, thinking and the ability to do daily tasks because diseases damage the brain, and it worsens over time. It is not an inevitable part of ageing and has no cure, but care and treatment can ease symptoms.Editorially complete
Asthma A chronic lung condition in which the airways become inflamed and narrow, causing cough, wheeze and shortness of breath. Most people control it well with inhalers, a written action plan and avoiding triggers.Editorially complete
Asthma in children A long-term lung disease in which the airways become inflamed and sometimes narrow, causing wheezing, coughing (especially at night), shortness of breath and chest tightness. It usually starts before age 5. There is no cure yet, but most children live normal lives with treatment, an asthma action plan and avoiding triggers. Severe breathing difficulty or blue lips need an ambulance right away.Editorially complete
Stroke A stroke happens when blood stops flowing to part of the brain. It is a medical emergency: call for an ambulance at the first sign of face drooping, arm weakness or speech problems.Editorially complete
Tuberculosis A contagious disease caused by bacteria that usually attack the lungs but can also affect the kidneys, spine and brain. It spreads through the air from a person with active disease. A person can carry the infection without symptoms and without spreading it (latent infection); active disease causes cough, fever, night sweats and weight loss and can be treated with antibiotics if the course is completed.Editorially complete
Obesity A chronic health condition in which body weight is higher than considered healthy for height, raising the chance of other health problems. It is usually measured with body mass index and has several treatment options chosen with a health care provider.Editorially complete
Migraine A condition causing a severe, throbbing headache usually on one side, with nausea and sensitivity to light and sound. Some people have an aura beforehand. Attacks can be managed by avoiding triggers and with treatment.Editorially complete
Psoriasis A chronic skin disease in which an overactive immune system makes skin cells multiply too quickly, producing thick red patches covered with silvery-white scales that may itch or hurt. It is not contagious and has no cure, but treatments can control it, and joint inflammation can accompany it.Editorially complete
Epilepsy A chronic brain condition in which seizures keep recurring because of abnormal electrical activity in the brain. It is not contagious, and many people can become seizure-free with the right treatment.Editorially complete
Infertility Infertility means not getting pregnant after a year or more of regular sex without contraception, or after 6 months if the woman is 35 or older. The cause can be in the woman, the man, both, or remain unexplained. Many cases can be treated, and a doctor decides which tests and treatments fit each couple.Editorially complete
Irritable bowel syndrome A chronic disorder causing repeated belly pain and changes in bowel habits (diarrhoea, constipation or both) without visible damage to the digestive tract. It does not lead to other health problems but can be painful and disruptive, and is managed with diet, lifestyle and medicines.Editorially complete
Metabolic dysfunction-associated steatotic liver disease Fat builds up in the liver without alcohol being the cause. It usually has no symptoms, is linked to obesity, diabetes and high blood fats, and weight loss and a healthy lifestyle are the main treatment.Editorially complete
Gout A type of arthritis that causes sudden attacks of severe pain, swelling, redness and warmth in a joint, often the big toe. It results from a build-up of uric acid forming crystals in the joint. It can be controlled well with medicines and lifestyle changes.Editorially complete
Transient ischemic attack A brief interruption of blood supply to part of the brain that causes the same symptoms as a stroke (weakness or numbness on one side, trouble speaking or seeing), but they usually go away within minutes. It is a medical emergency and a warning sign of a future stroke. You cannot tell at first whether it is a TIA or a stroke, so call an ambulance right away, even if the symptoms go away.Editorially complete
Cirrhosis Cirrhosis is permanent scarring of the liver, where scar tissue replaces healthy tissue and the liver works less well. It cannot be cured, but treating the cause may stop it getting worse.Editorially complete
Benign prostatic hyperplasia A non-cancerous growth of the prostate, a small gland below the bladder that makes semen and controls the flow of urine. It often causes difficulty starting to urinate, a weak stream and frequent urination, especially at night. According to the NHS it does not cause prostate cancer or raise the risk of it.Editorially complete
Acne A common skin disease in which hair follicles clog and pimples form, mostly on the face, neck, back, chest and shoulders. It is common in teenagers and young adults, can leave scars, and can be treated with creams and medicines.Editorially complete
Kidney stones Kidney stones are hard lumps that form in the kidneys from minerals in the urine. Small ones may pass unnoticed; larger ones can cause severe pain in the side or lower back.Editorially complete
Osteoarthritis The most common type of arthritis, in which joint tissues break down over time, causing pain, stiffness, swelling and trouble moving. It mostly affects the hands, knees, hips, neck and lower back; there is no cure, but it can be managed.Editorially complete
Type 1 diabetes An autoimmune condition in which the immune system destroys the insulin-making cells of the pancreas, so the body makes little or no insulin. People need insulin and regular glucose monitoring, and must know the warning signs of ketoacidosis.Editorially complete
Type 2 diabetes A long-term condition in which blood glucose rises because the body responds poorly to insulin and, over time, the pancreas cannot make enough. It often develops slowly, may cause no symptoms for years, and can be managed with lifestyle, medicines and regular follow-up.Editorially complete
Pancreatic cancer A cancer that starts in the pancreas, the organ that makes digestive enzymes and hormones. It often causes symptoms only late, and common signs are jaundice, unintended weight loss and belly or back pain.Editorially complete
Breast cancer Breast cancer is a disease in which cells in the breast grow out of control, usually starting in the milk ducts or the milk-producing lobules. The most common sign is a new lump or thickening in the breast or armpit. It mainly affects women and, rarely, men. It is found by examination, imaging and biopsy, and the care team agrees a treatment plan together with the patient.Editorially complete
Lung cancer Cancer that starts in the lungs when abnormal cells grow out of control. Smoking is the main cause, but people who never smoked can get it too. It may cause no symptoms at first, then a cough that will not go away, breathlessness, chest pain or coughing up blood. It is diagnosed with imaging and a tissue sample, and the care team chooses treatment based on the type, stage and general health.Editorially complete
Colorectal cancer Colorectal cancer starts in the large bowel (colon or rectum), often from growths called polyps. It may cause no symptoms at first; signs include changes in bowel habits, blood in the stool, belly pain that does not go away and unexplained weight loss. Screening can find polyps so they can be removed before they turn into cancer.Editorially complete
Anemia A condition in which red blood cells or their haemoglobin fall below normal, so too little oxygen reaches the body. The commonest cause is iron deficiency, and symptoms include tiredness, breathlessness, dizziness and pale skin.Editorially complete
Sickle cell disease A group of inherited blood disorders affecting haemoglobin, the protein that carries oxygen in red blood cells. The cells become stiff and crescent-shaped and obstruct blood flow, causing severe pain crises, anaemia and complications in several organs. It is inherited when a child receives a gene from each parent, and with the right care many people lead full lives.Editorially complete
Diabetic foot problems Diabetes can reduce feeling and blood flow in the feet, so cuts may go unnoticed and heal slowly. Daily foot care and regular foot exams help prevent serious complications.Editorially complete
Hypothyroidism A condition in which the thyroid gland does not make enough thyroid hormone for the body's needs. Symptoms develop slowly: fatigue, weight gain, feeling cold, dry skin. It is diagnosed with blood tests and treated with medicine that replaces the hormone.Editorially complete
Heart failure Heart failure means the heart cannot pump blood well enough for the body's needs. It does not mean the heart has stopped. It causes breathlessness, tiredness and swelling, and is managed with medicines, devices and lifestyle.Editorially complete
Prediabetes Blood glucose is higher than normal but not high enough to be called diabetes. It usually causes no symptoms, and lifestyle change can reduce the chance of progressing to type 2 diabetes.Editorially complete
Polycystic ovary syndrome A common hormonal condition in women of reproductive age. It often causes irregular or missed periods, extra hair on the face or body, acne and sometimes difficulty getting pregnant. There is no cure, but healthy habits and treatments chosen with a doctor help control symptoms and lower long-term risks such as type 2 diabetes.Editorially complete
Chronic obstructive pulmonary disease A group of long-term lung conditions that restrict airflow and cause breathlessness and cough. It cannot be cured but can be managed, and quitting smoking is the most important step.Editorially complete
Coronary heart disease The arteries that feed the heart narrow because of fatty deposits, so less blood reaches the heart muscle. It can cause chest pain (angina) or a heart attack, and some people have no symptoms before diagnosis.Editorially complete
Alcohol-associated liver disease Damage to the liver and its function from drinking alcohol heavily over a long period. It moves through stages: fat build-up (often without symptoms), inflammation, and scarring (cirrhosis) that usually cannot be reversed. Stopping alcohol is the main step in treatment according to the sources read.Editorially complete
Chronic kidney disease (CKD) A long-term condition in which the kidneys do not filter the blood as well as they should. It often causes no symptoms early on and is found by blood and urine tests. Care aims to slow it down and protect the heart.Editorially complete
Hypoglycaemia (low blood glucose) Blood glucose falls below a safe level, causing shakiness, hunger, sweating and confusion. Mild episodes are treated with fast-acting sugar; a severe episode with loss of consciousness is an emergency.Editorially complete
Osteoporosis A disease that weakens bones and lowers their density so they become fragile and break easily. It develops silently over years and is often found only after a fracture, but it can be detected early with a bone density scan and treated or prevented.Editorially complete
Fatigue Fatigue is a feeling of weariness or lack of energy and differs from drowsiness. It has many causes, from poor sleep and stress to anaemia, diabetes and heart, kidney or liver disease, and should be checked if prolonged without explanation.Editorially complete
Numbness and tingling Numbness and tingling are abnormal sensations often felt in the fingers, hands and feet. Causes range from prolonged posture to diabetes and nerve disease, and some, like stroke, are emergencies.Editorially complete
Excessive thirst Excessive thirst is an abnormal feeling of always needing to drink fluids. It can be temporary (a salty or spicy meal) or point to a condition such as diabetes, so persistent thirst without a reason should be checked.Editorially complete
Slow-healing wounds Cuts, sores or wounds that are slow to heal can signal diabetes and are especially concerning on the feet, where delayed care can lead to infection and complications.Editorially complete
Blurred vision Blurred vision is a loss of sharpness and inability to see fine detail. Causes range from presbyopia and cataracts to diabetes and stroke, and some are emergencies.Editorially complete
Polyuria (excessive urine volume) Polyuria means the body makes more urine than usual each day. It is not the same as urinary frequency, which means needing to urinate more often than usual. Common causes of a larger volume include diabetes and drinking a lot of water; it deserves checking if it lasts several days without explanation.Editorially complete
Unintentional weight loss Unintentional weight loss is a drop in body weight without trying. It may be linked to undiagnosed diabetes, an overactive thyroid, digestive problems or other conditions, and substantial loss needs evaluation.Editorially complete
Lipase test A blood test that measures lipase, a digestive enzyme made mostly in the pancreas. It helps doctors look for pancreas problems, especially acute pancreatitis.Editorially complete
Oral glucose tolerance test Blood glucose is measured while fasting and then after a sugary drink to see how your body handles glucose. It can take up to about 3 hours.Editorially complete
Ferritin test A blood test that measures ferritin, a protein that stores iron in the body, so it reflects your iron stores and helps detect too little or too much iron.Editorially complete
Creatinine & eGFR Creatinine is a muscle waste product filtered by the kidneys. The blood test measures it and an eGFR is calculated from it to estimate how well the kidneys filter.Editorially complete
Hemoglobin A1c A blood test showing your average blood glucose over roughly the past 2–3 months. No fasting is needed, and the result is a percentage.Editorially complete
Liver function tests A group of blood tests that measure substances made by or affected by the liver, such as enzymes, albumin and bilirubin. They help doctors screen for and monitor liver problems.Editorially complete
Lipid profile A blood test measuring total, LDL and HDL cholesterol and triglycerides, used to understand heart and artery risk.Editorially complete
Complete blood count (CBC) A group of blood tests that measure the number and size of blood cells — red cells, white cells, platelets and haemoglobin. It is often part of a routine check-up and helps diagnose anaemia and infections.Editorially complete
Uric acid test A blood or urine test that measures uric acid, a waste product made when the body breaks down purines. It helps diagnose gout and monitor the risk of kidney stones.Editorially complete
Fasting plasma glucose Blood glucose measured after fasting for at least 8 hours, usually in the morning. It shows your level at a single point in time.Editorially complete
Random plasma glucose Blood glucose measured at any time of day, even after eating and without fasting. It is useful when symptoms of diabetes are present.Editorially complete
Urine albumin-to-creatinine ratio A urine test that compares the protein albumin with creatinine to see whether the kidneys are leaking protein.Editorially complete
TSH test A blood test that measures thyroid-stimulating hormone (TSH), made by the pituitary gland. It is usually the first step in finding out whether the thyroid is overactive or underactive.Editorially complete
Insulin Insulin is a hormone made by the pancreas that helps glucose enter the body's cells for energy. It is used as a medicine when the body does not make enough, and people with type 1 diabetes must take it. The doctor decides the type, the delivery method and the amount.Editorially complete
Metformin Metformin is a prescription medicine mainly used for type 2 diabetes to help lower blood sugar. The doctor decides the dose and duration; do not change or stop it without medical advice.Editorially complete
SGLT2 inhibitors A class of oral medicines that make the kidneys pass some blood glucose out in the urine. Used in type 2 diabetes, and some members are also prescribed for heart and kidney conditions per the sources. Needs medical follow-up; may cause genital and urinary infections, dehydration, and rarely ketoacidosis.Editorially complete
GLP-1 receptor agonists Medicines that mimic a gut hormone released after eating: they prompt insulin release, slow stomach emptying and reduce appetite. Mostly injected pens; some are used for type 2 diabetes and some for obesity. Common effects are nausea, vomiting and diarrhoea; warnings concern the pancreas, gallbladder and thyroid.Editorially complete
Chest X-ray A chest X-ray is a quick image of the lungs, heart and chest bones; you hold your breath while it is taken.Editorially complete
CT scan (computed tomography) An X-ray scan that rotates around the body; a computer combines the data into detailed cross-section pictures. It usually takes only minutes, and a contrast dye is sometimes used.Editorially complete
MRI scan (magnetic resonance imaging) A scan using a strong magnet and radio waves to show soft tissue in detail, without ionising radiation. You lie still in a loud scanner, and the team must know about any metal or implanted devices.Editorially complete
Ultrasound (sonography) A scan that uses high-frequency sound waves that echo off body tissue to make live pictures, without ionising radiation. It is used to look at organs and to monitor pregnancy.Editorially complete
Endoscopy Endoscopy is a way to look inside the body with a thin flexible tube that has a small camera and light (an endoscope). It is used to find the cause of symptoms, take samples, or treat some problems.Editorially complete
Electrocardiogram A quick, painless test that records the heart's electrical activity through sticky electrodes on the skin. It shows heart rate and rhythm.Editorially complete
Echocardiogram An echocardiogram is an ultrasound scan of the heart that shows how well it is working.Editorially complete
Hematology A hematologist is a doctor who specializes in blood disorders such as anemia, bleeding and clotting disorders, and blood cancers.Editorially complete
Radiology (diagnostic and interventional) A radiologist is a physician who uses imaging methods to diagnose and manage patients and provide therapeutic options, acting as a consultant to the referring doctor.Editorially complete
Dermatology A dermatologist is a physician specializing in conditions of the skin, hair and nails, from mild problems to life-threatening ones.Editorially complete
Pulmonology A pulmonologist specializes in respiratory tract disorders.Editorially complete
Infectious diseases An infectious disease specialist is an expert in diagnosing and treating diseases caused by microorganisms: bacteria, viruses, fungi and parasites.Editorially complete
Otolaryngology (ENT) An ENT physician is trained in the medical and surgical management of diseases of the ears, nose, throat and related structures of the head and neck, in children and adults.Editorially complete
Oncology Oncology is the branch of medicine focused on diagnosing and treating cancer and caring for people with it; types include surgical, medical and radiation oncologists.Editorially complete
Anesthesiology An anesthesiologist is a physician who manages patients before, during and after surgical and diagnostic procedures, including control of pain and awareness.Editorially complete
Clinical nutrition (dietetics) Clinical nutrition (dietetics) is where dietitians give science-based food advice to help prevent or manage health conditions. Your health care provider may refer you to a dietitian for tailored recommendations.Editorially complete
Plastic and reconstructive surgery Plastic and reconstructive surgery repairs or rebuilds defects of form or function, whether present from birth or caused by injury or disease such as cancer, and also includes cosmetic enhancement. Every operation carries risks; decisions are made with a qualified surgeon.Editorially complete
General surgery A general surgeon has principal expertise in diagnosing and caring for diseases of the abdomen, digestive tract, endocrine system, breast, skin and blood vessels, and performs common operations on many parts of the body.Editorially complete
Gastroenterology A gastroenterologist specializes in digestive diseases and disorders.Editorially complete
Allergy and Immunology An allergist/immunologist evaluates, diagnoses and manages children and adults with allergic and immunologic conditions.Editorially complete
Rheumatology A rheumatologist is an internist or paediatrician with further training in diagnosing and treating musculoskeletal disease and systemic autoimmune conditions, using mostly non-surgical methods.Editorially complete
Sports medicine Sports medicine focuses on preventing and treating illness and injury related to sport and physical activity, mostly without surgery. It serves athletes and active non-athletes alike.Editorially complete
Physical medicine and rehabilitation (PM&R) A physiatrist evaluates and treats people with physical and/or cognitive impairments and disabilities, focusing on restoring function and independence.Editorially complete
Psychiatry A psychiatrist is a physician specializing in the diagnosis, treatment and prevention of mental, emotional and behavioral disorders.Editorially complete
Child and adolescent psychiatry A child and adolescent psychiatrist is a medical doctor who diagnoses and treats disorders of thinking, feeling and behavior in children and adolescents, working with their families. If a child's behavior is unsafe or they talk about hurting themselves or others, seek emergency help immediately.Editorially complete
Endocrinology and diabetes An endocrinologist treats endocrine gland problems such as diabetes, as well as hormonal and metabolic disorders.Editorially complete
Urology A urologist cares for diseases of the male and female urinary tract (kidneys, ureters, bladder and urethra) and of the male reproductive organs, with both medical and surgical treatment.Editorially complete
Obstetrics and gynecology An obstetrician/gynecologist focuses on women's health before, during and after childbearing years, diagnosing and treating reproductive system conditions and providing pregnancy and childbirth care.Editorially complete
Neurosurgery Neurosurgery is a surgical specialty that treats disorders of the nervous system, including the brain, spinal cord, peripheral nerves, spine, skull and their blood supply, in adults and children.Editorially complete
Vascular surgery A vascular surgeon is a specialist trained to treat diseases of the vascular system: the arteries and veins of the body except the brain and the heart.Editorially complete
Trauma care and surgery Trauma care is the rapid treatment of seriously injured patients, led by trauma surgeons. High-quality trauma care prevents deaths and reduces disability.Editorially complete
Orthopaedic surgery An orthopaedic surgeon is devoted to the prevention, diagnosis and treatment of disorders of bones, joints, ligaments, tendons and muscles, by medical, surgical and physical methods.Editorially complete
Family medicine A family physician is the first point of contact in care, providing prevention, diagnosis and chronic disease management for all ages and coordinating with specialists.Editorially complete
Dentistry Dentistry is concerned with preventing and treating diseases of the mouth, teeth and gums. Oral diseases are among the most common health conditions in the world.Editorially complete
Pediatrics A pediatrician practises the specialty concerned with the physical, emotional and social health of children from birth to young adulthood, covering prevention, detection and management of their problems.Editorially complete
Neurology Neurology covers the nervous system: the brain, spinal cord and nerves throughout the body.Editorially complete
Emergency medicine Emergency medicine deals with acute conditions that need immediate decisions and action to prevent death or disability. If life-threatening, call your local emergency number.Editorially complete
Ophthalmology An ophthalmologist addresses eye disorders and eye surgery, and also provides comprehensive eye exams, glasses prescriptions and medicines.Editorially complete
Cardiology Cardiology covers the heart and blood vessels, including coronary artery disease, heart failure and arrhythmias.Editorially complete
Nephrology A nephrologist treats people with kidney problems or related conditions, including high blood pressure.Editorially complete
Type 1 vs type 2 diabetes Both are diabetes, but type 1 is autoimmune with little or no insulin production, while in type 2 the body responds poorly to insulin over time. Symptoms overlap; cause, onset and treatment differ.Editorially complete
Quitting tobacco Quitting tobacco means stopping all forms of tobacco, such as cigarettes, waterpipe (shisha) and smokeless tobacco, as well as nicotine products such as e-cigarettes. CDC says quitting has health benefits at any age, and WHO says counselling and medication can more than double the chance of quitting successfully.Editorially complete
Healthy nutrition Healthy nutrition means choosing foods and drinks that support your health. WHO says a healthy diet protects against malnutrition and noncommunicable diseases such as diabetes, heart disease, stroke and cancer.Editorially complete
Mental wellbeing and coping with stress Mental wellbeing means being able to cope with everyday stress from life, work and relationships, and it is a core part of overall health. WHO says more than a billion people worldwide live with a mental health condition, and there are effective, healthy ways to manage stress and protect mental health.Editorially complete
Healthy ageing Healthy ageing means keeping the ability to do what matters to you as you grow older, even if you have some health conditions. WHO and other health bodies say habits such as being active, eating a balanced diet, not smoking and preventing falls help.Editorially complete
Fasting with a chronic condition Fasting with a chronic condition such as diabetes, kidney or heart disease can be safe for some people and risky for others, depending on the condition and how stable it is. WHO advises people with diabetes to consult a doctor before Ramadan to develop a safe fasting plan or appropriate alternatives.Editorially complete
Alcohol and its health effects Alcohol is a central nervous system depressant found in alcoholic drinks, and WHO says there is no level of drinking that is completely risk-free. The more someone drinks and the more often, the higher the risk to the liver, heart, certain cancers and mental health, according to CDC, NIAAA and MedlinePlus.Editorially complete
Vaccines for adults Vaccines train the immune system to recognize and fight harmful germs, protecting you from serious diseases before you meet them. Adults need vaccines too, because protection from some vaccines can fade over time; your doctor decides which ones you need.Editorially complete
Physical activity Physical activity is any bodily movement produced by muscles that uses energy, including leisure, transport, work and household tasks. WHO and CDC describe benefits for the heart, bones, mood and sleep.Editorially complete
Healthy sleep Sleep is a natural process that helps the body restore energy and supports learning, memory and health. CDC says getting enough sleep lowers the risk of chronic conditions such as type 2 diabetes, heart disease, high blood pressure and stroke.Editorially complete
Healthy weight A healthy weight is a weight for your height that lowers the risk of conditions such as heart disease, high blood pressure and type 2 diabetes. It is usually estimated with body mass index (BMI), but your health care provider can tell you what a healthy weight is for you.Editorially complete
Sun safety and skin cancer prevention Sun safety means protecting your skin and eyes from excess ultraviolet (UV) radiation, which can cause sunburn and raise the risk of skin cancer, according to the World Health Organization. Basic protection includes staying in the shade, wearing protective clothing, a hat and sunglasses, and using sunscreen, according to WHO and CDC.Editorially complete
Screening guide by age This guide gathers the age- and sex-based screening tests recommended by US health bodies (MedlinePlus and the USPSTF), such as blood pressure, cholesterol, diabetes, some cancers and osteoporosis. MedlinePlus advises seeing your health care provider from time to time even when you are healthy; your doctor and your local health authority decide what fits you.Editorially complete
Oral and dental health Oral and dental health means teeth, gums and a mouth free of pain and infection, so you can eat, speak and smile comfortably. WHO says oral diseases affect nearly 3.7 billion people worldwide even though they are largely preventable.Editorially complete
Embryology Gestation is the time from conception to birth. MedlinePlus says a typical pregnancy lasts 37–42 weeks and has three trimesters.Editorially complete
Histology A tissue is a group of similar cells working together as a unit. NCI SEER describes four main types: epithelial, connective, muscle and nervous tissue.Editorially complete
Physiology Physiology is about how body systems work. NCI SEER says survival depends on homeostasis, a state of relative constancy that is not rigid or fixed.Editorially complete
Abdomen Overview
Arm & hand Overview
Head Overview
Leg Overview
Chest Overview
Back Overview
Foot Overview
Health calculators These health calculators are simple tools that run entirely in your own browser, so nothing you type is sent anywhere. Each one is built on a formula published by a credible health source, with that source cited next to it. They are for general education only, not a diagnosis, and the result should always be read together with your doctor.Editorially complete
Blood pressure reading guide A blood pressure reading has two numbers: the top (systolic) and the bottom (diastolic), measured in mmHg. This guide shows the six categories from the American Heart Association's (AHA) blood pressure chart: Normal, Elevated, Hypertension Stage 1 and Stage 2, and two critical categories. The key point: a reading of 180/120 mmHg or higher together with symptoms such as chest pain or shortness of breath means calling emergency services in your country right away.Editorially complete
Lab result interpreter This tool shows which published reference band a common lab result (fasting glucose, A1C, cholesterol, eGFR, haemoglobin and similar) falls into, using ranges from NIDDK, CDC, MedlinePlus, the National Kidney Foundation and NHLBI. It is a general classification only — your doctor interprets your actual result in the context of your full health picture.Editorially complete
FINDRISC diabetes risk score FINDRISC is a short, eight-question tool developed by Finnish researchers to estimate a person's chance of developing type 2 diabetes over the next ten years, without an immediate blood test. The International Diabetes Federation (IDF) uses it for its World Diabetes Day public-awareness campaign, encouraging people with a higher result to see a primary care doctor for proper testing. This page explains the idea behind the questionnaire and its general result categories, but does not yet include an interactive calculator with the exact points for each answer (see Limits below).Editorially complete
Symptom checker This tool helps you pick one of 8 common adult presenting complaints (such as chest pain, fever, or headache) and shows general urgency guidance drawn from patient-facing NHS, MedlinePlus, and CDC pages. It sorts the signs into three tiers: seek emergency help now, get medical advice the same day, or book an appointment within days. It never diagnoses a disease, and every result ends with: see a doctor to confirm the diagnosis.Editorially complete
Types of medical studies Studies in people fall into two broad groups: experimental studies, where researchers decide who receives a treatment or intervention (such as clinical trials), and observational studies, where researchers only observe what happens. Each answers some questions well and has clear limits.Editorially complete
Correlation and causation Two things appearing together does not mean one caused the other. Many health headlines come from observational studies that find a “link” between a habit and a health outcome, but people with that habit may differ from others in many other ways that explain the result.Editorially complete
Peer review, preprints and retractions Journals usually certify research through peer review before publishing it. Some studies are posted publicly earlier as preprints, before peer review, and some published papers are later retracted. Knowing these states protects you from relying on findings that are not yet certified or have been withdrawn.Editorially complete
Find recruiting clinical trials Search the ClinicalTrials.gov registry for studies that are recruiting now or soon, by condition name, optionally filtered by country. Results show each study’s title, phase, status, type and countries, with a link to its official record.Editorially complete
Study reader Enter the DOI of any published study to see its title, journal and year, its type according to the U.S. National Library of Medicine’s publication types (such as randomized trial or systematic review), its approximate place in the evidence pyramid, and whether it has been retracted, corrected or flagged with an expression of concern.Editorially complete
How to read risk numbers A phrase like “cuts the risk in half” can mean a large or a very small difference, depending on the starting risk. Knowing the difference between absolute and relative risk is one of the most useful skills for understanding health news.Editorially complete
Evaluating health news and websites Media and the internet are major sources of health information. Much of it is reliable, but some stories miss important details or are confusing or misleading. A few simple questions about the source and the underlying study help you tell the difference.Editorially complete
Phases of clinical trials Before a new medicine or treatment reaches the public it passes through a series of trials in volunteers, called phases. Each phase answers different questions: safety first, then effectiveness, then comparison with existing treatments in large groups, then monitoring after approval.Editorially complete
The evidence pyramid Not all medical studies are equally able to answer “does this treatment work?”. The evidence pyramid is a simplified teaching tool that orders study types: systematic reviews that pool many studies at the top, then randomized controlled trials, then observational studies, and early signals such as case reports and lab or animal research at the base.Editorially complete
Transcatheter aortic valve replacement Transcatheter aortic valve replacement treats aortic stenosis by placing a replacement valve made from animal tissue inside the old valve through a catheter, without open-heart surgery. The FDA first approved a device in 2011 and expanded use to low-surgical-risk patients in 2019.Editorially complete
Monoclonal antibodies Monoclonal antibodies are immune-system proteins made in the lab that recognise specific targets. More than 80 therapeutic monoclonal antibodies had been approved in the United States by 2022, used in cancer, autoimmune diseases, infections and many other conditions.Editorially complete
Wearables and remote monitoring Wearables such as smartwatches carry sensors that track and transmit data such as heart rate. They are often used to monitor and self-manage chronic conditions, and range from general-wellness gadgets to FDA-regulated medical devices.Editorially complete
Artificial pancreas (automated insulin delivery) An artificial pancreas is a three-part system that mimics how a healthy pancreas controls blood glucose: a continuous glucose monitor, a program that calculates insulin needs, and an insulin pump. It is mainly used for type 1 diabetes; the FDA approved a hybrid system in 2016.Editorially complete
Deep brain stimulation and neurostimulation Deep brain stimulation treats symptoms of some movement disorders such as Parkinson’s disease, essential tremor and dystonia, and is also used for epilepsy. Leads in the brain are connected to a battery that sends electrical pulses. The FDA first approved it in 1997; it is not a cure.Editorially complete
Robotically-assisted surgery In robotically-assisted surgery the surgeon sits at a computer station and directs robotic arms. The device is not truly a robot, because it cannot operate without direct human control. The FDA has cleared it for specific laparoscopic procedures in several surgical specialties.Editorially complete
Liquid biopsy A liquid biopsy looks in blood or other body fluids for biomarkers shed by cancer cells, instead of taking a piece of the tumour. Some tests are FDA-approved for specific uses, such as guiding treatment for certain cancers and a blood test for colorectal cancer screening.Editorially complete
Artificial intelligence in medicine AI is used in medicine today in specific areas, including medical image analysis, clinical decision support and drug development. The key distinction is between a tool that supports a clinician — who can review the basis of its recommendation — and a system that works on its own within narrow, regulator-authorised limits. WHO stresses that humans should remain in control of medical decisions.Editorially complete
Telehealth Telehealth — sometimes called telemedicine — lets you see your health care provider by phone or video without going to their office. Many conditions can be handled this way, but it is not right for everyone or every condition.Editorially complete
Precision medicine Precision medicine tailors prevention, diagnosis and treatment to features of the person or the disease — for example testing a tumour for biomarkers to choose treatment. It is routine for some cancers but not yet part of routine care for most patients.Editorially complete
3D printing of medical devices 3D printing builds a three-dimensional object from successive layers of raw material. Commercially available 3D-printed medical devices include orthopaedic and cranial implants, surgical instruments, dental crowns, external prosthetics and devices matched to a patient’s anatomy.Editorially complete
Gene therapy Gene therapy modifies a person’s genes to treat or cure disease. It is approved today for a small number of conditions — including an inherited eye disorder, spinal muscular atrophy and sickle cell disease — and is being studied for others.Editorially complete
Cancer immunotherapy Immunotherapy helps the immune system fight cancer. Immune checkpoint inhibitors block an “off” signal sent to immune T cells so they can attack cancer cells. It is approved for many cancer types, but only a portion of patients respond.Editorially complete
Stem cell therapies Stem cells can become many types of cells. Their approved medical use today is mainly blood-forming stem cell transplants for blood cancers and some blood disorders. The FDA warns about unapproved “stem cell” products marketed for other conditions, which have caused harms including blindness, tumours and infections.Editorially complete
Continuous glucose monitoring Continuous glucose monitoring uses a device that automatically estimates glucose every few minutes through a sensor reading the fluid between cells. Doctors prescribe CGMs for adults and children, and in 2024 the FDA cleared the first over-the-counter CGM for adults who do not use insulin.Editorially complete
Genome editing (CRISPR) Genome editing lets scientists change DNA; its tools act like scissors that cut DNA at a specific spot. In December 2023 the FDA approved the first CRISPR-based therapy, for sickle cell disease, later extending it to transfusion-dependent beta-thalassaemia and to children aged 2 and older.Editorially complete
Genome sequencing and genetic testing A genetic test looks for changes in genes, chromosomes or proteins; more than 77,000 genetic tests are in use. Whole genome sequencing reads the order of every DNA “letter” and is increasingly used in healthcare and research.Editorially complete
mRNA technology Messenger RNA (mRNA) carries instructions to make a protein. mRNA vaccines use lab-made mRNA to teach our cells to make a protein piece so the immune system learns to recognise it. The FDA approved the first such vaccine in 2021 and another in 2024.Editorially complete
Cochlear implants A cochlear implant is a small electronic device that can provide a sense of sound to people who are deaf or severely hard of hearing, by bypassing damaged parts of the ear and stimulating the hearing nerve directly. The FDA first approved them in the mid-1980s; about 736,900 registered devices had been implanted worldwide by December 2019.Editorially complete
CAR T-cell therapy In CAR T-cell therapy, a patient’s own T cells are collected, engineered in the lab to make a receptor that helps them find cancer cells, and returned. The FDA approved the first one in 2017; all approved CAR T therapies so far are for blood cancers.Editorially complete
Pharmacogenomics Pharmacogenomics studies how genes affect a person’s response to medicines — why a drug helps some people, does nothing for others or causes side effects. Testing is used in clinical care for some medicines and conditions.Editorially complete
Tissue engineering Tissue engineering combines scaffolds, cells and biologically active molecules into functioning tissue. FDA-approved examples include artificial skin and cartilage, but the field still plays a relatively small role in patient care, and whole organs remain far off.Editorially complete
Bioprinted organs Researchers are trying to build living tissues and organs by combining cells with supporting scaffolds and biologically active molecules, including by 3D printing. Some simple engineered tissues such as skin and cartilage are FDA-approved but have limited use, while heart, lung and liver tissues remain a long way from being implanted in patients.Editorially complete
Organs-on-chips Organs-on-chips (tissue chips) are engineered microsystems that mimic the structure and function of the heart, kidneys, lungs and other organ systems. They are a research tool for developing drugs and predicting whether drugs will be safe or toxic in humans — not a treatment given to patients.Editorially complete
Digital twins in medicine A digital twin is a set of virtual information constructs that mimics the structure, context and behaviour of a real thing — such as a patient or a tumour — with two-way interaction between the virtual and the physical. In medicine, enthusiasm for the idea currently outweighs evidence of its success.Editorially complete
Induced pluripotent stem cells Induced pluripotent stem cells are mature adult cells that scientists have reprogrammed in the laboratory. Their use to replace damaged cells is being tested, including an early trial in eye disease, but they are not an approved treatment.Editorially complete
Nanomedicine Nanomedicine uses nano-sized carriers to deliver drugs to targeted tissues such as tumours. Some nano-based cancer drugs have been approved for years, but the use of nanotechnology for cancer diagnosis and treatment is largely still in development.Editorially complete
In vivo gene editing In in vivo gene editing the editing tools are given to the patient to correct a genetic fault in cells where they are, instead of removing cells and modifying them outside the body as in the approved sickle cell treatment. In 2025 NIH announced the first known case of a personalized gene-editing medicine given to a single patient.Editorially complete
Polygenic risk scores A polygenic risk score uses statistics to estimate how the collection of a person’s genetic variants affects their risk of a particular disease. The result is a probability, not a certainty, and health professionals do not yet use these scores routinely because there are no guidelines for practice.Editorially complete
Xenotransplantation Xenotransplantation means transplanting, implanting or infusing live cells, tissues or organs from an animal source into a human. Research focuses on organs from gene-edited pigs; use in people is still experimental, and the main hurdles are rejection and the risk of infection passing from the animal.Editorially complete
Personalized cancer vaccines Cancer treatment vaccines are a type of immunotherapy that treats cancer; personalized ones are made for each patient based on the molecular features of their tumour. Small trials have shown promising results, but larger trials are needed to confirm them.Editorially complete
Brain–computer interfaces A brain–computer interface picks up brain signals and translates them; it can help people with paralysis communicate by decoding neural signals into words. Implanted devices are still being tested in clinical studies with very few participants.Editorially complete