Health Conditions
Clear, medically-reviewed guides to common health conditions — symptoms, causes, treatment and prevention. Tap a category to browse.
High Blood Pressure (Hypertension)
High blood pressure, or hypertension, is a common condition where the long-term force of blood against your artery walls is high enough to eventually cause health problems. It often has no symptoms but is a major risk factor for heart disease and stroke.
High Cholesterol
High cholesterol means having too much of certain fats in your blood, which can build up in your arteries and raise the risk of heart disease and stroke. It usually has no symptoms and is found through a blood test.
BMI in Children and Teenagers Explained
Understanding a child or teenager's BMI is different from understanding an adult's. Because children are still growing, their BMI is interpreted using age- and sex-specific percentiles rather than the fixed adult categories. This guide explains what a child's BMI means, what the percentiles are, and how to make sense of the result.
Childhood Obesity
Childhood obesity means a child or teenager is carrying excess body weight to a degree that may affect their health, judged using age- and sex-specific growth charts rather than adult BMI categories. It has become common worldwide, and while it can affect a child's health, it is something families and healthcare teams can address together with supportive, practical changes.
Common Cold in Children
The common cold is the most frequent illness in childhood, caused by viruses that infect the nose and throat. Children catch colds often — several a year is entirely normal — as their immune systems are still developing. Most colds are mild and clear up on their own within a week or two, but knowing how to care for a child and when to seek help is useful for every parent.
Fever in Children
A fever in a child is a temperature of 38°C (100.4°F) or above, and it is one of the most common reasons parents seek advice. A fever is usually a sign the body is fighting an infection, and most are caused by minor illnesses that pass on their own. This guide explains how to care for a feverish child and, importantly, the warning signs that need urgent medical attention.
Healthy Weight for Children
Knowing whether a child is a healthy weight is not about a single target number, because children are constantly growing. Instead, a child's weight is assessed using age- and sex-specific growth charts and percentiles. This guide explains how a healthy weight is judged for children, and the everyday habits that help a child grow up healthy.
Acid Reflux and GERD
Acid reflux is when stomach acid flows back up into the food pipe, causing heartburn and other symptoms. When it happens frequently it is called gastro-oesophageal reflux disease (GERD). It is very common and usually manageable with lifestyle changes and treatment.
Food Poisoning
Food poisoning is illness caused by eating food contaminated with germs or their toxins. It typically causes diarrhoea, vomiting and stomach cramps, coming on within hours or days of eating. Most cases are mild and clear up within a few days, with staying hydrated being the priority.
Gallstones
Gallstones are hard stones that form in the gallbladder, a small organ that stores bile. Many people have gallstones without any symptoms, but sometimes they cause sudden, severe tummy pain and other problems. When they cause symptoms, treatment is usually needed.
Gastroenteritis (Stomach Bug)
Gastroenteritis is inflammation of the stomach and intestines, commonly called a stomach bug, that causes diarrhoea and vomiting. It is very common and usually caused by an infection that clears up within a few days. The main concern is dehydration, so replacing fluids is the priority.
Hemorrhoids (Piles)
Hemorrhoids, also called piles, are swollen blood vessels in and around the bottom (anus and lower rectum). They are very common, often causing discomfort, itching or bleeding. While they can be uncomfortable and worrying, most cases are not serious and improve with simple measures.
Irritable Bowel Syndrome (IBS)
Irritable bowel syndrome (IBS) is a common, long-term condition affecting the digestive system. It causes symptoms like tummy pain, bloating, and changes in bowel habits. While IBS can be uncomfortable and frustrating, it does not damage the bowel, and symptoms can usually be managed.
BPPV (Positional Vertigo)
BPPV (benign paroxysmal positional vertigo) is a common cause of brief, intense spinning triggered by certain head movements, like rolling over in bed or looking up. It happens when tiny crystals in the inner ear move out of place, and it can often be corrected with simple manoeuvres.
Deviated Septum
A deviated septum is when the thin wall between the two nostrils is off-centre or crooked, making one nasal passage narrower. It is very common, often causes no problems, but can lead to a persistently blocked nose, especially on one side, and sometimes snoring or sinus issues.
Ear Infection
Ear infections are common, especially in children, and occur when part of the ear becomes infected and inflamed. They often cause earache and can affect hearing. Many clear up on their own within a few days, though some need treatment, and knowing when to seek help is useful.
Earwax Buildup
Earwax is a normal, protective substance the ear makes to clean and defend itself, but sometimes it builds up and blocks the ear canal, causing muffled hearing or discomfort. Most cases can be eased safely at home, and it is important never to poke objects like cotton buds into the ear.
Glandular Fever
Glandular fever, also called infectious mononucleosis or 'mono', is a viral infection most common in teenagers and young adults. It causes a severe sore throat, extreme tiredness, fever and swollen glands, and while it usually clears on its own, the fatigue can linger for weeks.
Glue Ear
Glue ear is a build-up of fluid behind the eardrum, common in young children, that causes temporary dulled or muffled hearing. It often follows ear infections or colds, usually clears on its own within a few months, and is rarely serious.
Labyrinthitis
Labyrinthitis is inflammation of a part of the inner ear that controls balance and hearing, usually following a viral infection. It causes vertigo (a spinning sensation), dizziness and sometimes hearing changes, and while it can be very unpleasant, it usually settles over a few weeks.
Laryngitis
Laryngitis is inflammation of the voice box (larynx), most often caused by a viral infection or overusing your voice. It typically makes your voice hoarse or croaky, or causes you to lose it altogether, and usually clears up on its own within a week or two.
Ménière's Disease
Ménière's disease is a disorder of the inner ear that causes attacks of vertigo, fluctuating hearing loss, tinnitus and a feeling of fullness in the ear. The attacks come and go unpredictably, and while there is no cure, treatment can reduce how often and how severely they happen.
Mouth Ulcers
Mouth ulcers are small, painful sores that appear inside the mouth, on the tongue, gums or cheeks. They are very common, usually harmless, and normally heal on their own within a week or two, though some simple measures can ease the discomfort.
Nasal Polyps
Nasal polyps are soft, painless, non-cancerous growths that develop on the lining of the nose or sinuses, usually because of long-term inflammation. They can block the nose and reduce the sense of smell, and are often treated with sprays or, if needed, surgery.
Nosebleeds
A nosebleed happens when small blood vessels inside the nose break and bleed, and it is usually harmless and easily stopped at home. The key is to lean forward — not tip the head back — and pinch the soft part of the nose. Some nosebleeds, though, warrant medical attention.
Post-Nasal Drip
Post-nasal drip is the sensation of mucus running down the back of the throat, often causing throat clearing, a cough or a lump-like feeling. It is very common, usually caused by allergies, infections or irritation, and can normally be eased with simple measures.
Quinsy (Peritonsillar Abscess)
Quinsy, medically called a peritonsillar abscess, is a collection of pus that forms beside a tonsil, usually as a complication of tonsillitis. It causes a severe, often one-sided sore throat and needs prompt medical treatment rather than home care alone.
Sinusitis (Sinus Infection)
Sinusitis is inflammation of the sinuses, the air-filled spaces behind the face, usually following a cold. It causes facial pain or pressure, a blocked or runny nose, and reduced smell. Most cases are viral and clear up within a few weeks with self-care, though some need further treatment.
Snoring
Snoring is the noisy breathing that happens when air flows past relaxed tissues in the throat during sleep, making them vibrate. It is very common and often harmless, but loud snoring with pauses in breathing can be a sign of sleep apnoea, which needs medical attention.
Strep Throat
Strep throat is a bacterial throat infection caused by streptococcus bacteria. Unlike most sore throats, which are viral, strep throat is bacterial and usually treated with antibiotics. It causes a painful throat, often with fever, and is especially common in children.
Swimmer's Ear (Otitis Externa)
Swimmer's ear, medically called otitis externa, is an infection or inflammation of the outer ear canal. It often follows water getting trapped in the ear, causing a painful, itchy and sometimes discharging ear, and usually clears with ear drops from a doctor.
Tinnitus (Ringing in the Ears)
Tinnitus is the medical name for hearing a sound — often ringing, buzzing or hissing — that does not come from an outside source. It is very common, usually not a sign of anything serious, and while there is no simple cure, several approaches can make it much easier to live with.
Tonsillitis
Tonsillitis is inflammation of the tonsils, the two small glands at the back of the throat, usually caused by a viral or bacterial infection. It causes a sore throat, difficulty swallowing and often a fever. Most cases clear up within a week with self-care, though some need treatment.
Hyperthyroidism (Overactive Thyroid)
Hyperthyroidism, or an overactive thyroid, is a condition where the thyroid gland produces too much thyroid hormone. This speeds up the body's processes, causing symptoms like a racing heart, weight loss and anxiety. It is treatable, and with the right care most people manage it well.
Hypothyroidism (Underactive Thyroid)
Hypothyroidism, or an underactive thyroid, is a common condition where the thyroid gland does not produce enough thyroid hormone. This slows down many body processes, causing symptoms such as tiredness, weight gain and feeling cold. It is easily treated.
Type 2 Diabetes
Type 2 diabetes is a common long-term condition in which the body cannot use insulin properly, causing blood sugar levels to rise. It can often be prevented or managed effectively with lifestyle changes and, where needed, medication.
Gout
Gout is a common and painful form of arthritis caused by a build-up of uric acid, which forms sharp crystals in a joint — often the big toe. It causes sudden, severe attacks of pain and swelling, and can usually be treated and prevented effectively.
Osteoarthritis
Osteoarthritis is the most common type of arthritis, affecting millions of people. It develops when the protective cartilage in joints gradually wears down, causing pain, stiffness and reduced movement. While it cannot be reversed, a great deal can be done to manage symptoms and stay active.
Sciatica
Sciatica is pain caused by irritation or compression of the sciatic nerve, which runs from the lower back down through the hips and each leg. It typically causes pain radiating down one leg. Most sciatica improves within a few weeks with self-care, though some cases need further treatment.
Anxiety
Anxiety is a normal human emotion that everyone experiences. But when worry and fear become persistent, overwhelming, and interfere with daily life, it may be an anxiety disorder — one of the most common mental health conditions. The good news is that anxiety is very treatable, and effective help is available.
Depression
Depression is a common but serious mental health condition that affects how you feel, think and handle daily life. It is much more than feeling sad or going through a rough patch, and it is not a sign of weakness. Importantly, depression is treatable, and with the right support most people improve.
Iron Deficiency
Iron deficiency happens when the body does not have enough iron, which it needs to make haemoglobin, the substance in red blood cells that carries oxygen. It commonly causes tiredness and can lead to iron deficiency anaemia. It is common and usually treatable with iron and dietary changes.
Vitamin B12 Deficiency
Vitamin B12 deficiency happens when the body does not have enough vitamin B12, which is essential for making red blood cells and keeping the nervous system healthy. It can cause tiredness, and if untreated, nerve problems. It is treatable, usually with supplements or injections.
Vitamin D Deficiency
Vitamin D deficiency means your body does not have enough vitamin D, a nutrient essential for healthy bones, muscles and immune function. It is very common worldwide and can often be corrected with sunlight, diet and supplements.
Asthma
Asthma is a common long-term condition affecting the airways in the lungs, causing them to become inflamed and narrow. This leads to symptoms like wheezing, breathlessness and coughing. With the right treatment, most people control asthma well and live normal, active lives.
Bronchitis
Bronchitis is inflammation of the bronchi, the main airways of the lungs, usually causing a cough that may bring up mucus. Acute bronchitis often follows a cold or viral infection and clears up within a few weeks. It is common and usually not serious, though it can be uncomfortable.
Cold and Flu
Colds and flu are common viral infections of the nose, throat and airways. Though they share symptoms, flu tends to be more severe and come on faster. Most people recover at home within a week or two, but knowing how to tell them apart and when to seek help is useful.
COVID-19
COVID-19 is an illness caused by a coronavirus that affects the respiratory system and sometimes the whole body. Symptoms range from mild, cold-like signs to more serious illness. Most people recover at home within a week or two, though some are at higher risk and a minority develop longer-lasting symptoms.
Hay Fever (Allergic Rhinitis)
Hay fever, also called allergic rhinitis, is a common allergic reaction to pollen and other airborne allergens. It causes sneezing, a runny or blocked nose, and itchy eyes. While there is no cure, symptoms can usually be controlled well with avoidance measures and treatments.
Pneumonia
Pneumonia is an infection that inflames the tissue in one or both lungs, usually caused by bacteria or viruses. It causes a cough, fever, and difficulty breathing. While many people recover well with treatment, pneumonia can be serious, especially in young children, older adults and those with other conditions.
Eczema
Eczema is a common condition that makes the skin dry, itchy and inflamed. The most common type, atopic eczema, often starts in childhood, though it can affect anyone at any age. While there is no cure, eczema can usually be well controlled with good skincare and the right treatment.
Psoriasis
Psoriasis is a common long-term skin condition where skin cells build up into thick, scaly patches. It happens because the immune system speeds up the skin's renewal process. While there is no cure, a range of treatments can control symptoms well, and most people manage it successfully.
Shingles
Shingles is a painful rash caused by the reactivation of the chickenpox virus, which stays dormant in the body after a childhood infection. It usually appears as a band of blisters on one side of the body. While it often clears within a few weeks, early treatment helps, and a vaccine can reduce the risk.
Kidney Stones
Kidney stones are hard deposits that form in the kidneys and can cause severe pain as they pass through the urinary tract. They are a common problem, and while an attack can be intensely painful, most stones can be treated, and there is a lot you can do to prevent them returning.
Urinary Tract Infection (UTI)
A urinary tract infection (UTI) is a common infection of the bladder, urethra or kidneys. Most affect the bladder and cause burning when passing urine and a frequent urge to go. They are usually easily treated but sometimes need prompt medical care.