Platelets are the blood cells in the body responsible for stopping bleeding and the standard range is (100-300) x 10^9/L. Below the normal range is thrombocytopenia and above the normal range is thrombocytosis. Thrombocytopenia is relatively common in clinical practice, and there are various causes such as infections and drugs that can cause thrombocytopenia, especially when viral infections, such as the flu, or certain anti-inflammatory and painkilling drugs, as well as certain anticoagulant drugs, such as heparin, etc., can cause a decrease in the number of platelets. Also many blood system diseases, such as aplastic anemia, immune thrombocytopenic purpura, myelodysplastic syndrome, leukemia, etc., can cause a decrease in platelets. If the cell count is severely reduced, platelet transfusion therapy is often required, and sometimes recombinant human thrombopoietin treatment is applied. The most common cause of thrombocytosis is primary thrombocytosis, a myeloproliferative disorder that often requires the application of hydroxyurea therapy.