Thrombocytopenia
(Low Platelet Count)

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Medical Author:

Siamak T. Nabili, MD, MPH

Siamak T. Nabili, MD, MPH

Dr. Nabili received his undergraduate degree from the University of California, San Diego (UCSD), majoring in chemistry and biochemistry. He then completed his graduate degree at the University of California, Los Angeles (UCLA). His graduate training included a specialized fellowship in public health where his research focused on environmental health and health-care delivery and management.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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• Thrombocytopenia Overview
• Thrombocytopenia Causes
• Thrombocytopenia Symptoms
• When to Seek Medical Care
• Exams and Tests
• Thrombocytopenia Treatment
• Self Care at Home
• Medical Treatment
• Medications
• Next Steps
• Follow-up
• Prevention
• Outlook
• Synonyms and Keywords
• Author and Editor
• Viewer Comments: Thrombocytopenia - Experience
• Viewer Comments: Thrombocytopenia - Cause

Thrombocytopenia Overview

Thrombocyte is the medical term for platelet. Thrombocytopenia means a lower platelet count in the blood compared to the normal range. Thrombocytosis refers to a greater number of platelets compared to the normal range.

Platelets are important elements in the blood that are important for blood coagulation (clotting and prevention of bleeding). The normal platelet count ranges between 150,000 and 450,000 per microliter (one-millionth of a liter). Although the number of platelets is decreased, their function may remain intact in most cases of thrombocytopenia.

All blood cells (white cells, red cells, and platelets) are made in the bone marrow. Platelets are derived from larger cells in the bone marrow called megakaryocytes. Fragments of megakaryocytes are platelets, which are released into the bloodstream. Only about 2/3 of platelets released into the blood stream circulate in the blood, and the remaining 1/3 is typically captured by the spleen. The life cycle of platelets is usually about 7-10 days; therefore, the old ones are continuously being replaced by new ones.

Picture of a blood clot