Yes, blood platelets dropping is a sign of concern as beyond a point this can result in bleeding into the organs. I am sorry but yes, that stage can also be life threatening. Hence the cause for the drop in platelets needs to be found, whether it is due to less production at the bone marrow or high breakdown or due to platelets being trapped in the spleen. The treatment will depend on the cause. Common causes are Vit B12 and folic acid deficiency, leukemias, lymphomas, decreased production of thrombopoietin by liver, Dengue fever, HIV, hemolytic anemias, etc. Blood transfusions and plasma exchange are the prescribed treatments. Immunoglobulins are given through veins for a rapid increase in platelets counts. Do discuss this with your doctor. Take care!