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IQWiG

IQWiG is an independent scientific institution in Germany. It is funded through contributions from the German statutory health insurance funds. Its legal responsibilities include the assessment of diagnostic tests and medical treatments. InformedHealth.org is the English-language version of IQWiG’s German website Gesundheitsinformation.de. It provides the general public with independent, ad-free and cost-free information on many common health issues.

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Our content is developed according to international quality standards and includes articles, graphics and films. We are a diverse team with backgrounds in science, medicine and journalism. We base our information on both high-quality scientific studies and the needs of patients and consumers. Our team ensures that the content of InformedHealth.org is easy to understand, complete and up to date.

Further topics

What are immunological tests?

Immunological tests can be used for various purposes, such as detecting viral infections, checking whether someone has an allergy, discovering colore...

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Colorectal cancer

Colorectal cancer is sometimes considered to be a disease that typically affects men. That's not true: Although it is more likely to develop at an ea...

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Cervical cancer

Cervical cancer is usually a rare consequence of an infection with particular sexually transmitted human papillomaviruses (HPV). Infections are proba...

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Gingivitis and periodontitis

A gum inflammation (gingivitis) is usually harmless and goes away quickly. But it might spread to the periodontium (the soft tissue and bone that sup...

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How does the knee work?

The knee joint connects the upper and lower leg to one another. It is needed for pretty much all forms of movement with your legs – whether running, ...

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How do joints work?

Joints are movable connections between two bones. Each joint is made up of the surfaces of the bones involved, a joint cavity and a joint capsule.

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Osteoarthritis of the knee

Osteoarthritis of the knee typically starts with knee pain, at first only during or after movement. The risk is increased by things like being overwe...

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Using medication

Using medication sounds easy but it can be complicated, like when you need to use several medications over a longer period of time. What's the best w...

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Obsessive-compulsive disorder (OCD)

People with obsessive-compulsive disorder (OCD) may constantly wash their hands because they are afraid of germs, or may not be able to stop counting...

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Generalized anxiety disorder

We all feel scared sometimes. This can help protect us in dangerous situations: It makes us more alert so that we can react quickly. But fear can bec...

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Head lice

Head lice are tiny parasites that live in our hair and feed on blood from our scalp. Their bites can itch. They usually lay their eggs close to the s...

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Understanding thyroid tests

The thyroid gland is a vitally important endocrine (hormone) gland that is mainly involved in the body’s energy metabolism. It is located at the fron...

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How does the pituitary gland work?

The pituitary gland regulates various body functions and plays an important role in balancing hormone levels in the body. It is a protrusion at the b...

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How does the thyroid gland work?

The thyroid gland is a vital hormone-producing gland: It plays a major role in the metabolism, growth and development of the human body. It helps to ...

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Heavy periods

While some women hardly have any problems due to their period, others regularly feel tired and unwell. This is often due to pain and very heavy perio...

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Overactive thyroid (hyperthyroidism)

The thyroid gland regulates a lot of functions in the body. It is said to be overactive if it makes too many thyroid hormones. This can lead to sympt...

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Underactive thyroid (hypothyroidism)

If you constantly feel tired, have a slow pulse and constipation, you may wonder why. These types of symptoms can be caused by various things, but th...

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Uterine fibroids

Many women have benign (non-cancerous) growths known as fibroids in or on their womb (uterus). Most fibroids are small and don't cause any problems. ...

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Acute pancreatitis

Acute pancreatitis is an inflammation of the pancreas that typically causes very sudden and very severe upper abdominal pain. The pain is so extreme ...

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Deep vein thrombosis (DVT)

Deep vein thrombosis (DVT) occurs when a blood clot forms in a vein. This can cause symptoms like tenderness, skin redness, swelling in the lower leg...

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Carpal tunnel syndrome

Most people know what it's like to wake up in the night and realize that their hand has "fallen asleep." The hand then feels numb or tingly. Carpal t...

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Pneumonia

Pneumonia often leads to a sudden high fever, the feeling that you are very unwell, a cough and shortness of breath. People who are otherwise in good...

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Psoriasis

Psoriasis is characterized by clearly defined patches of red and scaly skin. This non-contagious condition typically starts in adulthood and comes an...

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Gallstones

We all have abdominal pain and digestion problems from time to time. In most cases they're harmless. But if you have cramping pain in your upper abdo...

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Psoriatic arthritis (Psoriasis with joint inflammation)

Psoriatic arthritis leads to pain and stiffness in several joints, as well as exhaustion. It is usually caused by psoriasis. Various treatments can r...

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Hearing loss and deafness in children

In Germany and other countries, babies are routinely given hearing tests immediately after birth. The goal is to diagnose and treat hearing problems ...

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Endometriosis

"Endometriosis? Never heard of it." This is what many people say, even though it is a common condition in women. While some hardly notice that they h...

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Metastatic breast cancer

Sometimes breast cancer is only detected when it has already spread to other parts of the body (metastasis). With well-planned and individualized tre...

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Sinusitis

The typical signs of sinusitis (inflamed paranasal sinuses) are a stuffy nose, pain and a feeling of pressure in the forehead or jaw. Sometimes it de...

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Eczema

Eczema is an inflammatory skin condition that often occurs in children. The main symptom is a very itchy rash. Acute flare-ups can greatly affect qua...

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How can you self-manage and adjust anticoagulants in the long term?

Oral anticoagulants are used to prevent blood clots from forming. This can lower the risk of certain cardiovascular diseases, especially strokes.

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Age-related macular degeneration (AMD)

It's normal for vision to gradually get worse with age. Some people also have medical conditions that further affect their vision. Age-related macula...

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What are blood thinners (anti-clotting medications) and how are they used?

Anti-clotting medications prevent blood clots from forming in the blood vessels and heart. This lowers the risk of medical problems that are caused b...

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Atrial fibrillation

The most common sign of atrial fibrillation is an irregular heart rate that is often too fast. Although the condition isn’t immediately life-threaten...

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Measles

Measles is caused by viruses and is very contagious – both in children and adults. The typical signs of measles are a light red rash and flu-like sym...

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Mumps

Mumps is a viral infection that has become rare since the introduction of a routine vaccination. It is usually spread through tiny droplets of spit t...

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Rubella (German measles)

Rubella usually goes unnoticed or only causes mild cold-like symptoms. Later, a pink or red spotty skin rash might develop. If a woman has rubella ea...

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What are blood clots and what causes them?

When we are injured, our body stops the bleeding by forming a clump of blood (a blood clot) that closes the wound. But sometimes blood clots form in ...

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Type 2 diabetes

Many people who are diagnosed with type 2 diabetes are completely taken by surprise – for instance, if high blood sugar levels are discovered during ...

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Gestational diabetes

Pregnant women are often surprised to find out they have gestational diabetes because it usually doesn’t cause any symptoms. But this type of diabete...

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Common colds

Sneezing and a sore throat are often the very first signs you are getting a cold. Once your nose has become stuffy, you may feel weak and generally i...

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Croup

If young children have a cold and the area around their larynx (voice box) becomes inflamed, it's known as croup. The typical symptoms include a bark...

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Wrist injuries

Breaking a fall with your hands can sometimes lead to a wrist injury. If the wrist joint is overstretched or bent too far, the joint capsule, ligamen...

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Dislocated kneecap

When a kneecap is dislocated, it comes out of the groove that it normally fits into. This is painful and may look frightening. It mainly happens duri...

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Patellofemoral pain syndrome (runner’s knee)

Pain at the front of the knee is usually caused by overuse. It is especially common in people who do a lot of sports, such as running, mountaineering...

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Scarlet fever

Doctors can usually diagnose scarlet fever quite easily based on the typical rash and a dark-red tongue, sometimes referred to as a “strawberry tongu...

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Menopause

What happens in a woman’s body in the time leading up to menopause? What symptoms might accompany the hormonal changes, and how can they be relieved?...

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Seborrheic dermatitis

Seborrheic dermatitis is a non-infectious skin condition. It leads to scaly patches of skin with oily dandruff-like flakes, especially on the face an...

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Presbyopia

Most people start noticing the effects of presbyopia in their mid-forties: It becomes harder to see close-up things clearly. For instance, y ou have ...

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Lazy eye (amblyopia) in children

Amblyopia is a common vision problem in children. It is caused when one eye provides sharper images than the other eye does. Because the brain prefer...

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Small objects in the eye

Whether you are outside biking or doing DIY projects at home – it’s easy for small objects to get into your eye. There, they can injure the surface o...

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Dulaglutide (Trulicity) for the treatment of type 2 diabetes

Dulaglutide (trade name: Trulicity) has been approved in Germany since November 2014 for the treatment of type 2 diabetes when diet and exercise alon...

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Wisdom teeth

Many people associate wisdom teeth with "being pulled," a bruised and swollen cheek, and an ice pack. Removing wisdom teeth is usually unpleasant and...

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Insect venom allergies

We all get stung or bitten by insects every now and then – and most people end up with a small, red, itchy bump as a result. But those who are allerg...

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Allergic contact dermatitis

In allergic contact dermatitis, the immune system overreacts to certain substances – sometimes to very small amounts – that normally wouldn’t cause a...

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Drug allergies

Medications can have a number of side effects, including allergic reactions. People who have a drug allergy are often no longer sure which medication...

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Food allergies

In food allergies, even small amounts of the food can be enough to trigger an allergic reaction (e.g. itching and swelling in the mouth and throat, o...

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Hay fever

If you have hay fever, you're not alone: About 1 in 4 people have this allergy. Various medications and allergen-specific immunotherapy often provide...

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Allergies to animals

People aren't allergic to the fur of animals, but rather to proteins that are found on the animal's dander (skin flakes), sweat or spit. The allergy ...

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Allergies

Allergies arise if the body's immune system overreacts to substances (allergens) that are usually harmless, such as pollen. The symptoms are sometime...

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Dust mite allergies

Dust mite allergies usually develop in childhood or puberty. The symptoms, such as sneezing, are caused by substances that are mainly found in the fe...

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Benign paroxysmal positional vertigo

If you feel like everything is spinning around you and rocking from side to side, you probably have vertigo. Vertigo can occur while standing, walkin...

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How can I find good-quality information about the coronavirus?

The coronavirus is on everyone’s mind right now. Many people are finding out about it on the internet or from sharing on social networks. There is a ...

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Localized prostate cancer

Prostate cancer is the most commonly diagnosed type of cancer in men. But it is also one of the types of cancer with the best chances of recovery. It...

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Tendon overuse injuries (tendinopathy)

If you regularly put a lot of strain on a tendon, for instance when doing sports or certain work-related activities, it might become sore. Tendon ove...

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Tooth decay

Preventing tooth decay is basically child's play: It's all about a healthy diet, less candy and thorough dental hygiene. Read about the most importan...

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Shoulder pain

Shoulder pain is one of the most common orthopedic problems. It usually arises beneath the bone that forms the “roof” of the shoulder (the acromion)....

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Hernias

Most hernias occur when part of the bowel or peritoneum pushes through a gap in the abdominal wall. Inguinal (groin) hernias are the most common kind...

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Misaligned teeth and jaws

People are considered to have misaligned teeth or jaws if their set of teeth is very different to that of most others. This type of problem is common...

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Epilepsy

In epilepsy, the brain or certain parts of the brain are too active. Some people have their first seizure in childhood, while others have their first...

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Warts

Most people get warts at some point. Warts are contagious and can be very persistent. Children and teenagers are particularly likely to get them beca...

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Acute cystitis

Cystitis is very common in women. It is caused by a bacterial infection. The main symptom is a burning pain when peeing, often accompanied by an incr...

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Irritable bowel syndrome

The typical symptoms of irritable bowel syndrome (IBS) include abdominal pain, constipation and diarrhea. Although IBS isn't dangerous, the symptoms ...

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Acne

Most teenagers will have pimples at some point. Severe acne can be very distressing. But there are a number of things that can help, although it usua...

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Varicose veins

About one in five adults have varicose veins. These bumpy, bluish veins are mainly a cosmetic issue for most people. But they sometimes cause a feeli...

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Hair loss in chemotherapy

Cancer treatments can have serious side effects. Many people find chemotherapy-related hair loss on their scalp and body to be especially upsetting. ...

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Premature ejaculation

Ejaculation is considered to be premature if "coming" too soon becomes a problem and affects a man’s sex life. Various treatment options are then ava...

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Hemophilia

Hemophilia is a disease that causes problems with blood clotting. It makes blood clot (coagulate) much more slowly than usual. The worse the ability ...

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Tinea versicolor

If a fungus grows a lot it may lead to a medical condition. Tinea versicolor is one example. This skin condition is caused by a yeast (fungus), and i...

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How does the menstrual cycle work?

During the monthly hormone cycle, the membranes lining the inside of the womb prepare for the possible implantation of a fertilized egg. The membrane...

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Oral thrush

Most of us are familiar with our teeth feeling somewhat “fuzzy” after eating sweets. But if your entire mouth feels cottony all the time, your sense ...

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Canker sores (mouth ulcers)

Canker sores (mouth ulcers) are among the most common medical conditions that affect the mucous membranes lining the mouth. When a canker sore develo...

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Period pain

Although menstruation is a normal part of a woman's life, severe period pain need not be. Women don't have to simply put up with it – menstrual pain ...

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Parkinson’s disease

Parkinson's disease is a disease of the nervous system. It typically occurs in old age and reduces the person's ability to move. Parkinson’s usually ...

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Varicoceles

Infertility can be caused by various things. One possible cause is a varicose vein in the scrotum, also known as a varicocele. Varicoceles are quite ...

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Vaginal yeast infection (thrush)

Vaginal yeast infections are particularly common in women of childbearing age. The symptoms include itching, burning and abnormal vaginal discharge. ...

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Fever in children

Most parents will know what it's like to feel worried when their child has a hot, red face and high temperature. Fevers in children are usually cause...

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Hepatitis B

Hepatitis is the medical term for an inflammation of the liver. It is often caused by an infection with certain viruses. Hepatitis B is mainly spread...

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Middle ear infection

Acute middle ear infections are one of the most common illnesses in infants. Many parents then face sleepless nights with a child that cries, has an ...

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Tick bites

Although ticks can carry and spread disease, tick bites usually don't cause any health problems. You're much less likely to develop tick-borne enceph...

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Corns

Corns develop when an area of skin is repeatedly exposed to pressure or rubbing over a long period of time. They mainly occur on your toes and on the...

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Tinnitus

Most people experience tinnitus from time to time, for example after a loud concert. But some people hear the typical buzzing or ringing sounds all t...

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Ovarian cysts

Ovarian cysts are fluid-filled sacs in the ovaries. Some have tissue inside them. They are usually non-cancerous (benign) and most of them go away on...

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Kidney stones

Kidney stones are very common, especially between the ages of 40 and 60. These small, hard crystals form in the renal pelvis, and can move down into ...

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Neck pain

Neck pain can make your neck muscles tense up, preventing you from moving your head normally. The pain sometimes radiates into your arms or head, too...

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Low back pain

Most of us know what low back pain feels like. It usually starts suddenly and then goes away again on its own after a few days or weeks. Low back pai...

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Heart valve diseases

When people talk about heart valve diseases, they usually mean conditions caused by damage to heart valves over time. These tend to occur in older ag...

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Tonsillitis

Acute tonsillitis causes symptoms such as a sore throat, difficulty swallowing, fever and tiredness. Tonsillitis that keeps coming back within short ...

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Enlarged tonsils and adenoids

Many children between the ages of three and six years have enlarged tonsils or adenoids. This usually isn’t anything serious. But enlarged tonsils an...

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Obstructive sleep apnea

If you get enough sleep but still feel run down during the day, you may have obstructive sleep apnea (OSA). Many people who have sleep apnea snore an...

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Heartburn and GERD

Many people are familiar with heartburn – a burning pain between your stomach and throat. In gastro-esophageal reflux disease (GERD), these symptoms ...

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Osteoarthritis

In the early stages of osteoarthritis, the joint usually only hurts when you put strain on it. The pain can get worse over time, affecting your every...

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Non-melanoma skin cancer

There are different kinds of non-melanoma skin cancer. They are much more common than malignant melanoma. Non-melanoma skin cancer grows very slowly,...

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Melanoma

Melanoma often looks like a dark mole. It may grow fast and spread to other parts of the body (metastasis). The treatment options mainly depend on ho...

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Lactose intolerance

Stomach pain, bloating and "gas" are all typical digestion problems that some people have after eating or drinking dairy products. This may happen be...

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Brain aneurysm

A brain aneurysm is a berry-shaped bulge in an artery in or near the brain. Aneurysms often go unnoticed. But some people have symptoms – or an incre...

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Vocal nodules

Vocal nodules typically make your voice hoarse, and it may sound raspy and breathy too. These small non-cancerous nodules usually go away again if yo...

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Phimosis

Nearly all boys are born with a foreskin that won’t pull back (phimosis). This protects the sensitive head of the penis from rubbing against things, ...

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Osteoporosis

Having weak bones that easily break is a sign of osteoporosis. It's normal for bone tissue to break down as you grow older, but osteoporosis speeds u...

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Post-traumatic stress disorder (PTSD)

We often hear about things like serious accidents, natural disasters, or sexual abuse in the news. These traumatic events can have a great impact on ...

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Pelvic organ prolapse

For various reasons, the connective tissue in women’s pelvic floor may become weaker. This can cause the womb, bladder or the end part of the bowel t...

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Tenosynovitis

If a tendon sheath is overused, it can become inflamed and swollen. Known as tenosynovitis, this most commonly occurs in the hands, arms and feet. Th...

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Bursitis

Signs of bursitis include swelling and pain – for instance, in an elbow or knee. It can arise when too much pressure is put on one of the protective ...

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Frozen shoulder

Frozen shoulder starts very gradually. At first the pain is mild, but it then gets worse and can make it difficult to sleep through the night. Over t...

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Cold sores

Cold sores lead to the formation of painful blisters around the lips, typically only on one side of the mouth. People who have had a cold sore in the...

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Gastritis

Gastritis is common. The symptoms include stomach pain, heartburn, nausea and feeling full. It is usually caused by certain bacteria or anti-inflamma...

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Bunions

Bunions are among the most common foot deformities. They often don’t cause any problems – or only minor problems. But sometimes the foot becomes incr...

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Nail fungus

Nail fungus is very common. Experts think that it often develops from untreated athlete's foot. It then takes a while to get rid of the brittle, disc...

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Migraine

A migraine is very different from a “normal” headache: Migraines are typically associated with moderate to severe headaches that only affect one side...

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Tennis elbow

Tennis elbow is usually the result of repetitive movements or too much strain – for instance, during sports like tennis or when doing manual labor. T...

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$Ankle fractures$

Ankle fractures

If you're unlucky, twisting your foot badly can result in a broken ankle. This is a more serious injury that may affect one or more bones. Is surgery...

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Ankle sprains

Ankle sprains are one of the most common types of injury. When an ankle is twisted, the ligaments are overstretched. In the worst case, they might te...

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Bedwetting

Bedwetting is more common among children and teenagers than many people think. Regular nighttime “accidents” can be troubling for the entire family. ...

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Erysipelas and cellulitis

Erysipelas and cellulitis are skin infections that can develop if bacteria enter the skin through cuts or sores. Both infections make your skin swell...

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Pregnancy and birth

Pregnancy is a time of change, especially if it's your first. Parents-to-be may have feelings ranging from joy and hope to worries and anxiety: How w...

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Chronic kidney disease

Older people are especially prone to developing chronic kidney disease. The most common causes are diabetes and high blood pressure. The disease ofte...

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Surgery

People who are preparing to have surgery usually have a lot of questions: What are the chances of success? What risks are associated with it? What ca...

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Health care in Germany

In Germany, it's usually not hard to find medical help if you become ill. There is an extensive network of easily accessible places to go for treatme...

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Heart failure

Many people with heart failure avoid physical activity in order to prevent symptoms like shortness of breath and trouble breathing. But physical exer...

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Asthma

In asthma, people's airways become so narrow (temporarily or permanently) that it's difficult for them to breathe. With the right treatment, though, ...

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Enlarged hemorrhoids

We all have hemorrhoids. Hemorrhoids are normal “cushions” of tissue filled with blood vessels, found at the end of the rectum. They only cause probl...

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High cholesterol

Find out the difference between “good” and “bad” cholesterol, which levels are considered to be normal, and what some related medical terms mean. Als...

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Acute bronchitis

In acute bronchitis, the lower airways (bronchi) are temporarily inflamed. The cough is usually dry at first. Later on, it may develop into a phlegmy...

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Smoking

Most people who smoke decide to stop smoking at some point. But quitting may be harder than expected. It usually takes several attempts before you ac...

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Falls in older people

There are plenty of tripping hazards in the average home - an edge of the carpet sticking up, a lose cable, or slippery tiles in the bathroom. When o...

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Coronary artery disease

Coronary artery disease (CAD) is caused by the narrowing of the large blood vessels that supply the heart with oxygen. These vessels are called coron...

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Breast cancer

Being diagnosed with breast cancer often makes people feel very frightened and anxious. But if you get breast cancer for the first time and it hasn’t...

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Stroke

The signs of a stroke include a sudden and severe headache, paralysis and speech difficulties. These problems are caused when part of the brain doesn...

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Contraception

The introduction of the birth control pill in the 1960s was something of a revolution. Many hormonal contraceptives are available nowadays. More rece...

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Alzheimer's disease

Alzheimer's disease is the most common cause of dementia. People with Alzheimer's become forgetful and increasingly have difficulty expressing themse...

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Type 1 diabetes

In type 1 diabetes, the pancreas can only produce insulin in small quantities or can’t produce any at all. People who have type 1 diabetes need to in...

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Premenstrual syndrome

Sometimes even women don't quite understand what happens to them on the days leading up to their period. Women who have premenstrual syndrome (PMS) m...

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Abdominal aortic aneurysm

An abdominal aortic aneurysm may arise if the wall of the aorta becomes less elastic, for example due to the normal aging process, smoking or high bl...

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