Thrombocythemia is a state of high platelet (thrombocyte) include in the blood. Typical include is in the scope of 150,000 to 450,000 platelets for every microlitre of blood.but examination is possibly thought of if as far as possible surpasses 750,000. At the point when the reason is obscure, the term thrombocythemia is utilized, as either essential thrombocythyemia or basic thrombocythemia. The condition emerges from an issue in the bone marrow cells that overproduce the platelets. The reason for the flaw is obscure, and this sort isn't normal. At the point when the reason is referred to, for example, another turmoil or malady, the term thrombocytosis is liked, as either auxiliary or responsive thrombocytosis. Receptive thrombocytosis is the most widely recognized sort and however it can regularly have no side effects it can at times incline to apoplexy. Interestingly, thrombocytopenia alludes to unusually low blood platelet numbers in the blood.