Photo of man holding his knee in pain (PantherMedia / Fabrice Michaudeau) Hemophilia is a disease that causes problems with blood clotting. It makes people's blood clot (coagulate) much more slowly than usual. This means that wounds take longer to heal.

Poor clotting also makes internal bleeding more likely. This can be caused by a fall or a crush injury. Sometimes there is no clear cause, though. Internal bleeding may damage organs, muscle tissue or joints.

Hemophilia is an umbrella term for several different diseases. The most well-known are hemophilia A and hemophilia B. Each form is caused by the lack of a particular protein that helps blood to clot: People with hemophilia A do not have clotting factor VIII (eight), while people who have hemophilia B lack clotting factor IX (nine). Hemophilia A is more


The poorer the blood's ability to clot, the more severe the symptoms. There are three main levels of severity:

Mild hemophilia usually does not cause any major problems in everyday life. It often goes unnoticed until puberty or adulthood when bleeding after surgery or a deep cut lasts longer than normal.

Someone with moderate hemophilia may have occasional bleeding, but usually only following surgery or an injury. Only rarely will there be no apparent cause.

People who have severe hemophilia often have internal bleeding though, which can be painful. Bleeding for no known reason is common in severe hemophilia, especially bleeding in the elbows, wrists, shoulders, hips, knees and ankles. Arm and leg muscles are often affected too. Bleeding in the brain, throat or abdomen is especially dangerous. The symptoms of severe hemophilia are apparent from a very young age: Babies bruise very easily. As the children become more active, learn to walk and put more strain on their joints and muscles, bleeding starts occurring there.

Bleeding in the joints is extremely painful. They become swollen and hurt when moved, and often become inflamed.


Hemophilia is usually inherited. It is caused by the lack of a clotting factor in the blood. This is almost always due to a defect in the gene for the clotting factor.

There are usually two copies of every gene. The genes for the clotting factors are on the X chromosome. The cells in women's bodies contain two X chromosomes, whereas the cells in men's bodies only contain one.

So if a woman has a defective gene on one of her X chromosomes, having a normal gene on the other X chromosome can usually prevent any blood clotting problems. It is very rare for both genes to be defective in women.

But if a man has a defective gene it cannot be overridden by a normal one, so hemophilia is more common in men.


Hemophilia affects about 2 out of 10,000 men. It is estimated that there are 10,000 men with hemophilia in Germany, about 3,000 to 5,000 of whom have a severe form of the disease.


A joint that has already been affected by internal bleeding is likely to be affected again. Recurrent bleeding can deform a joint, stiffening and slowly destroying it (hemarthrosis). Advanced stages of hemarthrosis can make it nearly impossible to move your arms or legs, and a wheelchair or other mobility aid may then be necessary.

Major bleeding into muscle tissue increases the pressure on surrounding tissue, blood vessels and nerves. This can affect blood circulation and damage the nerves.

Internal bleeding in the brain is rare, but it can impair your thinking ability, concentration or sense of balance. Severe cranial (in the brain) bleeding is life-threatening. Bleeding inside organs, the abdominal cavity or in the mouth and throat region is also dangerous: Bleeding in the throat area, for example, can make it hard to breathe. Bleeding in the abdominal cavity can cause major blood loss and damage vital organs.


Hemophilia treatment involves replacing the missing clotting factor. There are two main approaches:

In on-demand treatment, as the name suggests, the missing clotting factor is injected as and when you need it rather than on a regular basis. For example, it may be injected

  • to stop active bleeding, or
  • before a medical procedure, for instance surgery or the pulling of teeth, in order to limit blood loss.

If someone has severe hemophilia, preventive (prophylactic) treatment is usually recommended. Here, the clotting factor is administered regularly to prevent excessive bleeding. The medication is usually injected into a vein every few days to improve the blood's general ability to clot and to lower the risk of bleeding. People who have hemophilia can learn to do this themselves if they are shown how to and with a little practice.

Other medications to improve the blood's clotting ability are only used in milder forms of hemophilia. These include tranexamic acid and desmopressin. The hormone desmopressin causes clotting factors stored in the blood vessels to be released.

Sometimes further medications are used as well. For instance, painkillers can be used to treat severe pain. Painkillers that do not affect blood coagulation, such as ibuprofen, are suitable for this purpose. Acetylsalicylic acid (the drug in medications like Aspirin) is not suitable because it increases the risk of bleeding.

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