Too high platelets

What are high platelets?

There is a wide range of platelet counts that are harmless or normal for humans. Healthy people have a platelet count between 150,000 and 450,000 platelets / µl blood. From a value of 450,000 platelets µl, the platelet count is too high.
In medical terms, if the platelet count is too high, it is called thrombocytosis.

However, symptoms and serious complications, such as a blood clot, usually only occur when the platelet count exceeds 800,000 platelets / µl.


The most common cause of an increased platelet count is what is known as reactive or secondary thrombocytosis. This leads to an increased platelet count due to another underlying disease. For example at:

  • acute infections
  • chronic inflammatory diseases
  • bleeding or
  • malignant tumor diseases

  • Essential thrombocythemia is a rare cause. The cause of the increased platelets lies in a malfunction of the stem cell in the bone marrow from which the platelets are formed.
  • Other bone marrow disorders can also cause thrombocytosis.

Essential thrombocythemia

Essential thrombocythemia is a very rare disease.

A malfunction of the stem cell in the bone marrow causes too many platelets to be formed and released into the blood.
Platelet counts over 1,000,000 / µl are not uncommon.

This increases the risk of blood clots (thrombosis).

  • You might also be interested in: Detect thrombosis

When the blood vessels are damaged, the thrombocytes have the task of clumping and sealing the injury. If the platelet count is as high as in essential thrombocythemia, there is a risk that blood clots will form, block the vessels and disrupt the blood flow, even without injury.

On the one hand there is an increased occurrence of blood clots, on the other hand there is also increased bleeding because the platelets produced are not functional.

Reactive thrombocythemias

Different processes e.g. In the event of illness or inflammation, the body reacts with different mechanisms. This makes sense as it tries to fight the cause and prevent major damage.

However, this often leads to changes in the blood count.
A common response from the body is an increase in blood platelets.

Triggers are for example:

  • acute infections,
  • chronic inflammatory diseases,
  • bleeding or
  • malignant tumor diseases.

In reactive thrombocythemia, the problem is not the increased platelet count, but the underlying disease.
As a rule, this is also noticeable through other symptoms. Treatment of the underlying disease also normalizes the platelet count.

Diseases of the spleen

In addition to its important role in immune function, the spleen is also important for blood purification. It recognizes old blood cells, including platelets, and breaks them down. So it is not surprising that when the spleen is diseased, there are changes in the blood count and changes in the platelet count.

However, the body is able to live without the spleen. If the spleen e.g. Has been seriously damaged in an accident, it must be removed during an operation.
One speaks of a so-called splenectomy. After a splenectomy, many people have high platelets.

Are you wondering whether you have this cause?

  • Read our article on this: Pain in the spleen

Possible consequences

The possible consequences depend on the cause of the platelets that are too high. Even in a range that is too high, platelets do not initially have any direct consequences. However, the underlying disease can lead to various consequences. From a very high platelet count, which does not normally occur if the thrombocytosis is secondary to an underlying disease, serious consequences are possible.

There is a significantly increased risk of thrombosis (clots).
If such a clot forms in a pulmonary vein, it can lead to a life-threatening pulmonary embolism.

If the platelets are also inoperable, there is also an increased risk of bleeding. People with essential thrombocythemia are particularly hard hit, as this can lead to greatly increased and inoperable platelets in the course of the disease.
By normalizing or reducing the greatly increased platelet count, the risk of thrombosis also decreases.

  • This article may also be of interest to you: Measures for thrombosis prophylaxis

Laboratory values

The platelet count can be measured in the laboratory as part of a normal blood sample.
From a value of over 450,000 platelets / µl, the platelet count is increased. A slightly increased value is usually not a bad thing and has no bad consequences.
From over 100,000 platelets / µl, however, there is an increased risk of thrombosis.

In addition to the increased number of platelets, the shape of the platelets can also be changed.
In essential thrombocythemia, they are often too large and inoperable.
In addition, blood clotting (ability of the blood to clot / clump) can be tested in various laboratory tests.

Can that also be cancer?

The likelihood that cancer is responsible for an increased platelet count is relatively low - but not 100% excluded.

Cancer means a lot of stress for the body, to which the body reacts differently.
Many cancer sufferers have abnormalities in their laboratory values. An increased platelet count is not uncommon.

However, even with acute infections, which are much more common, the body reacts with an increased platelet count. Too many platelets in the blood are therefore by no means a specific sign of cancer.
In addition, the various cancers usually make themselves noticeable through other symptoms, which are more specific.

When does it get dangerous?

When injured, platelets have the task of clumping together in the blood, sealing the vessel wall and thus stopping the bleeding.
If there are too few platelets there is a risk of bleeding; if there are too many platelets, clumps, i.e. blood clots or thrombosis, occur.

However, there is a significantly increased risk of blood clots only if the platelet count exceeds 800,000 platelets / µl.
However, the platelets rarely rise that high.

These symptoms tell me that I am sick

Usually too many platelets go unnoticed. Those affected therefore have no typical symptoms.

Symptoms only appear when the platelet count is very high. These symptoms include microcirculation disorders or blood clots (thrombosis).
Other symptoms occur depending on the cause.
With essential thrombocythemia, bleeding is another common symptom.


Colloquially, thrombosis is referred to as a blood clot.

The blood clot is made up of clumped platelets that have been activated incorrectly and then clog a blood vessel. Thromboses are particularly common in the legs.
There is then swelling and a dull pain.
In addition, there is a feeling of heaviness in the legs and overheating.

The most dangerous thing is a blockage of a pulmonary vein.
In this case one speaks of a pulmonary embolism.
This can be fatal.

Are you unsure whether you have a thrombosis?

  • Find more information at: Detect thrombosis


If the thrombocytosis arose as part of another disease, the underlying disease must first be treated.

If there is an increased risk of thrombosis, it is advisable to initially keep the risk low by taking general measures.
This can be done by:

  • does not smoke,
  • Effectively treats cardiovascular diseases,
  • lead a good lifestyle with a healthy diet and plenty of exercise.

If this is not enough, blood thinners must be used.
In essential thrombocythemia, ASA (aspirin) is often used, provided there is no increased risk of bleeding.
ASA is a platelet aggregation inhibitor. These inhibit the clumping of blood platelets.

  • You can find more information about drugs for thrombosis here: Drugs for thrombosis prophylaxis

If a thrombosis has already occurred, drugs to thin the blood are also used.
Heparin is normally used here acutely.
Sometimes surgery is needed to remove the blood clot.
This is often followed by a compression treatment, for example with compression stockings.

Do you want to keep your risk of thrombosis as low as possible?

  • Read the articles from the category: Thrombosis prophylaxis


The duration and prognosis depend on the cause of the increased platelets.
In many cases it is only a short-term or medium-term increase in platelets, which after treatment of the underlying disease, e.g. an infection.

In chronic illnesses, the platelet count changes over and over again, sometimes it is higher, sometimes it is a little lower. A role can e.g. play how well the disease is adjusted at the moment.

There is no cure for essential thrombocythemia, which is directly caused by platelets. Medicines can only treat the symptoms of the disease.
In the case of essential thrombocythemia, however, a normal life expectancy can be expected in most cases.
However, there is an increased risk of developing other diseases that are related to blood formation.

Course of disease

The course of the disease is very different and depends on the cause.
Some causes, such as infections, subside within a few weeks and the platelet count returns to normal during the healing phase.

Chronic inflammatory diseases such as the chronic inflammatory bowel diseases, or cancers, have a much more serious disease course.

Platelets and white blood cells too high

It is not uncommon for platelets and leukocytes (white blood cells) to be increased at the same time, as leukocytes are also involved in many body reactions, e.g. Infections are increased.

This is the body's adaptive response to fight the infection.
They are an important part of the immune system.

Excessive leukocytes and platelets can also occur in essential thrombocythemia.

Can I take the pill if my platelets are too high?

In principle, platelets that are too high are not a reason why the pill should not be taken.

Thrombocytosis in and of itself does not necessarily increase the risk of thrombosis. However, it is advisable to talk to the attending doctor or gynecologist.
The risk of thrombosis (blood clots) depends largely on how high the platelets are and what is causing them.

The risk of thrombosis is increased in particular with essential thrombocythemia as the cause or a very high platelet count.
Taking the pill as well increases this risk of thrombosis even further.

Are you worried about possible side effects when taking the pill?

  • Find out more at: Thrombosis while taking the pill or side effects of the pill

Therefore, in this case, a detailed discussion should take place with the gynecologist about alternative contraceptive methods and the risk of taking pills.
Other methods of contraception without the risk of thrombosis would be preferable to the pill.

Are you looking for an alternative method of contraception besides the pill?

  • Find out more at: Hormone-free contraception

Too high platelets during pregnancy - I should be aware of that

If your blood values ​​change during pregnancy, it is easy to worry. Too high platelets during pregnancy are rare and in most cases not very pronounced.
It is important to get enough rest and recovery if an infection is the cause.
A doctor can also be consulted for clarification.
In general, drink enough and exercise.

Existing essential thrombocythemia increases the risk of maternal thrombosis and miscarriage. The risk of miscarriage can presumably be reduced by taking a low dose of ASA.
Overall, around 60% of women with essential thrombocythemia have normal pregnancy.

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