Normal Platelet Count: Causes, Symptoms & Management of Abnormal Levels

Introduction

A healthy platelet count is a vital aspect of our overall health, as it helps our blood clot appropriately in response to injury. Understanding the normal range of platelets is essential in detecting any imbalances or deviations from the norm that could lead to complications.  

In this article we will discuss in detail about platelet counts, providing valuable information on what constitutes a normal range, as well as the factors that can affect these counts. We will explore the causes and symptoms of abnormal platelet counts and discuss the diagnostic and management options available. Lastly, we will touch upon the impact of the COVID-19 pandemic on platelet counts and how to maintain good health.  

Overview of Platelets and Their Function

What are platelets?

Platelets, also known as thrombocytes, are colourless, disc-shaped cell fragments that are produced in the bone marrow and circulate in the blood¹. They play a significant role in maintaining our health by facilitating blood clotting and wound repair.  

Formation of platelets

Our bone marrow produces platelets in a process named megakaryopoiesis. These platelets come from larger cells known as megakaryocytes¹. They break off tiny fragments as they mature and form platelets.  

Functions of platelets in the body

Platelets perform several key roles, which are as follows.   

• Starting blood clots in response to injury¹.  
• Helping wound repair by releasing growth agents¹.  
• Supporting the immune system by releasing antimicrobial peptides¹.  
• Teaming up with other blood cells, like white blood cells, for the right immune response.  

How do platelets stop bleeding?

When a blood vessel is damaged, platelets become active. They stick to the injured area and form a patch. They then release blood clot forming chemicals¹. The result is a blood clot that stops the wound from bleeding and helps it heal.  

Understanding Normal Platelet Count

It is important to know the normal range for platelet count and what factors may change this count.  

Normal platelet range for adults and children

The normal count of platelets in both adults and kids falls between 150–400×10⁹/L of blood². But research shows some small differences based on whether you’re male or female.  

Factors influencing the platelet count  

Parameters like age, gender, genes, and health issues can all affect platelet count.   

• Age: The number of platelets normally reduces with age².  
• Gender: Studies² show men and women may have a slightly different platelet count range.  
• Genetic and ethnic changes: Your genes or race can alter the normal platelet count range². 
• Health conditions: Some health issues can impact platelet counts example in cases of anaemia or cancer³.  

Platelet count blood tests

A complete blood count (CBC) test can provide vital data about your platelets.  

• For the test, usually, a health worker will take some blood from a vein in your arm and then send the sample to a laboratory for analysis. The pathologist will measure the average amount of platelets in your blood. If this number is higher or lower than normal, it can indicate the presence of an underlying disorder. 

Causes of Abnormal Platelet Counts

Abnormal platelet counts can be a result of a few issues. This could be because of health problems, medicine, and various other causes.  

Low platelet count (Thrombocytopenia)

If your platelet count dips below 150,000/mcL, this is known as thrombocytopenia³. The cause might be that the body isn’t making enough platelets, or too many platelets might be destroyed or stored up in certain organs.  

• Problems with bone marrow: Conditions like aplastic anaemia or certain types of cancers may affect platelet production³.  
• Fast destruction of platelets: Several health issues can make the body destroy platelets at a quick pace, which are as follows.   
  • Autoimmune diseases, such as lupus or immune thrombocytopenia (ITP)³  
  • Severe bacterial infections involving the blood (bacteraemia), and viral fevers like dengue.  
• Medicines and substances that can cause a low platelet count Some drugs and substances may affect platelet production or how they work. These include the following³. 
  • Blood-thinning drugs  
  • Chemotherapeutic drugs  
  • Quinine present in tonic water, or certain leg cramp drugs  
  • Drinking a lot of alcohol 

You may have an inherited or acquired platelet disease such as Bernard-Soulier Syndrome (BSS) if the findings of your platelet function test are abnormal. You may inherit genetic illnesses from your family. Although the abnormalities exist from birth, symptoms might not appear until later in life. Disorders that are acquired do not exist at birth. They might be brought on by medications, environmental exposure, or other illnesses. There are instances where the cause is unclear⁹.

Dr. Siddharth Gupta, B.A.M.S, M.D

High platelet count (Thrombocytosis)

A platelet count above 450,000/mcL is known as thrombocytosis⁴. This count could be due to an innate issue with the bone marrow or it could be due to an external factor or another health problem.  

Causes of high platelet counts

A few things can result in high platelet counts. These are as follows⁴.   

• Infections
• Iron deficiency anaemia
• Haemolytic anaemia  
• Inflammatory bowel disease  
• Certain kinds of cancers
• Tuberculosis

Symptoms of Abnormal Platelet Counts

The signs that point to abnormal platelet counts can be different. It depends on whether the platelet count is high or low.  

Low platelet count symptoms

Signs of thrombocytopenia could include the following⁵:   

• Bruising easily (purpura)  
• Small bleedings into the skin that looks like a rash of tiny red-purple dots (petechiae)⁶  
• Long-lasting bleeding from cuts  
• Bleeding from gums or nose  
• Blood in urine or stool  
• Heavy menstrual bleeding  
• Feeling tired  
• Bigger size of spleen  

High platelet count symptoms

Often, people with a high platelet count don’t notice any symptoms. But sometimes, those with thrombocytosis may have abnormal bruising or bleeding. A high platelet count may also be associated with a higher risk of blood clots. Warning signs like headache, dizziness, chest pain or numbness must be watched out for⁶.  

When to see a doctor?

If you notice signs of a platelet disorder, you must discuss it with your doctor. Unstoppable bleeding or signs similar to a heart attack or stroke calls for immediate medical help.  

Diagnosis and Management of Abnormal Platelet Counts

Finding the cause of altered platelet count is key to managing it well.  

How is a low platelet count diagnosed?

To find out if a person has a low platelet count, a health expert will take a thorough medical history and perform a physical examination. They’ll also review the person’s past medical issues. Further tests like blood tests or bone marrow aspiration and biopsy may be advised if needed.  

• Medical history: Finding out about the person’s present and past health history as well as family history can help to identify possible causes⁷. This can include medicines, a family history of bleeding disorders, or certain health problems.  
• Physical examination: During the physical examination, the doctor will look for evidence of bruising, petechiae, or an enlarged spleen⁷.  
• Tests: Blood tests such as a CBC⁷, platelet antibodies⁵, and blood smear tests⁷, can offer critical data about one’s platelet count. Sometimes, bone marrow tests⁷ and biopsy⁵ are needed to assess platelet production.  
  • Blood tests: These tests can check platelet count and provide more detail about underlying causes⁷.  
  • Ultrasound: An ultrasound may be performed if there is a suspicion of an enlarged spleen⁷.  
  • Bone marrow aspiration and biopsy: A health expert may do a bone marrow aspiration and biopsy⁵. This is to look into platelet production and find the cause of a low platelet count.  

Management for low and high platelet count

Management for unusual platelet counts will depend on how severe the condition is and its root cause. Management options may include the following⁸:   

• Blood or platelet transfusions.  
• Changing medications that cause a low platelet count.  
• Steroids, immune globulin, or other medicines that suppress the immune system.   
• Removing the spleen (in cases related to the spleen and a low platelet count).   

For individuals with abnormal platelet counts, an important part of management is avoiding risky activities which may cause injuries that bleed. Keeping track of their platelet levels and discussing personal and family histories as well as any medicines or health aids being taken with the doctor is also essential. This can help find possible causes and make informed decisions about management.  

Complications and Risks Associated with Abnormal Platelet Counts

Abnormal platelet counts can result in serious, even life-threatening, problems.  

• Issues that come from low platelet count

If a person’s platelet count falls below 20,000/mcL, dangerous internal bleeding can happen⁵. Severe thrombocytopenia can lead to bleeding in the brain. This can be deadly. 

• Problems that come from high platelet count

When platelet count is too high, it can cause blood clots to form. This can lead to deep vein thrombosis, blockage in the lung (pulmonary embolism), myocardial infarction or stroke⁴. These can be life-threatening as well.  

Conclusion

Understanding the importance of keeping a healthy platelet count is crucial for best health. If we understand the signs of abnormal platelet counts and seek timely medical advice, we may be able to manage any health issues impacting our platelets.  

Regular screenings including routine doctor visits and timely blood testing are important for all individuals to detect abnormal platelet counts or any other issues at an early stage and avoid future complications.  

Frequently Asked Questions (FAQs)

References

1. Ghoshal K, Bhattacharyya M. Overview of platelet physiology: its hemostatic and nonhemostatic role in disease pathogenesis. ScientificWorldJournal. 2014 Mar 3;2014:781857. doi: 10.1155/2014/781857. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC3960550/  

2. Balduini CL, Noris P. Platelet count and aging. Haematologica. 2014 Jun;99(6):953-5. doi: 10.3324/haematol.2014.106260. Available from: https://pmc.ncbi.nlm.nih.gov/articles/PMC4040891/  
3. National Heart, Lung, and Blood Institute. Thrombocytopenia [Internet]. Bethesda (MD): National Institutes of Health; 2022 Jul [cited 2025 Jul 2]. Available from: https://www.nhlbi.nih.gov/health/thrombocytopenia 
4. Rokkam VR, Killeen RB, Kotagiri R. Secondary Thrombocytosis [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan– [updated 2024 Aug 6; cited 2025 Jul 2]. Available from: https://www.ncbi.nlm.nih.gov/books/NBK560810/ 
5. Pietras NM, Gupta N, Justiz Vaillant AA, et al. Immune Thrombocytopenia [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan– [updated 2024 May 5; cited 2025 Jul 2]. Available from: https://www.ncbi.nlm.nih.gov/books/NBK562282/ 
6. National Heart, Lung and Brain Institute. Platelet Disorders Symptoms [Internet]. Bethesda (MD): National Institutes of Health; 2022 Jul [cited 2025 Jul 2]. Available from: https://www.nhlbi.nih.gov/health/platelet-disorders/symptoms#:~:text=Symptoms%20of%20a%20high%20platelet%20count%20are%20mostly%20caused%20by,that%20is%20larger%20than%20normal 
7. National Heart, Lung and Brain Institute. Diagnosis of platelet disorders [Internet]. Bethesda (MD): National Institutes of Health; 2022 Jul [cited 2025 Jul 2]. Available from: https://www.nhlbi.nih.gov/health/platelet-disorders/diagnosis 
8. National Heart, Lung, and Blood Institute. Treatment of platelet disorders [Internet]. Bethesda (MD): National Institutes of Health; 2022 Jul [cited 2025 Jul 2]. Available from: https://www.nhlbi.nih.gov/health/platelet-disorders/treatment 
9. MedlinePlus. Platelet tests [Internet]. Bethesda (MD): National Library of Medicine; [updated 2024 Mar 6; cited 2025 Sep 10]. Available from: https://medlineplus.gov/lab-tests/platelet-tests/

Disclaimer: The information provided here is for educational/awareness purposes only and is not intended to be a substitute for medical treatment by a healthcare professional and should not be relied upon to diagnose or treat any medical condition. The reader should consult a registered medical practitioner to determine the appropriateness of the information and before consuming any medication. PharmEasy does not provide any guarantee or warranty (express or implied) regarding the accuracy, adequacy, completeness, legality, reliability or usefulness of the information; and disclaims any liability arising thereof.

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