Overview of Low Platelet Count (Thrombocytopenia)

Reviewed/Revised Sept 2023
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What is a low platelet count?

Platelets are small cells that circulate in your bloodstream and help your blood clot. They're made in your bone marrow like other blood cells. Platelets are also called thrombocytes.

Your blood normally has a certain number of platelets in a given sample of blood. That number is your platelet count.

  • With a low platelet count, you bleed easily

  • You may have tiny purple spots on your skin and get nosebleeds and bleeding gums

  • A very low platelet count may cause bleeding in your brain or severe bleeding from your intestines

  • Many things can cause a low platelet count

  • Doctors may do tests to look for the cause

  • Doctors treat the cause of the low platelets and may give you a platelet transfusion

What causes a low platelet count?

Many things can cause a low platelet count:

What are the symptoms of a low platelet count?

The main symptom of low platelet count is excessive bleeding. You may have:

  • Tiny red spots on your skin or inside your mouth

  • Bruises after very minor injuries

  • Bleeding gums

  • Heavy menstrual periods

You're more likely to bleed the lower your platelet count drops. People who have very few platelets may bleed heavily from their intestines or have life-threatening bleeding in their brain.

What tests do I need for a low platelet count?

Sometimes the problem that caused your low platelet count is obvious, such as being pregnant, having a severe infection, or taking a certain medicine.

If doctors aren't sure why your platelet count is low they may do:

  • Blood tests

  • Bone marrow biopsy (taking a sample of bone marrow to look at under a microscope)

How do doctors treat a low platelet count?

The main thing is to treat whatever caused the low platelet count. For example, if taking a medicine caused your low platelet count, your doctor will stop giving you the medicine if possible. If it was caused by an infection, your doctor will treat the infection.

Rarely, doctors will give you:

  • A platelet transfusion

  • Medicines to help your blood clot better

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