A reduction in the number of platelets (called thrombocytopaenia) is said to exist if the platelet count falls below 1,50,000 per ul. The causes for it include - decreased platelet production, increased platelet destruction or platelet pooling in the spleen. Each of these states may result from a large number of conditions. Most times platelets are reduced due to increased destruction called ITP which may result from fever, infections, drugs etc. The patient needs to be examined by a physician and advised appropriately as the platelet counts usually come up on their own or after therapy.