Anagrelide (Thromboreductin) is indicated for treatment of essential thrombocythaemia. The decision for treatment has to be taken individually for each patient depending on the number of platelets, on age, on the clinical symptomatology and anamnesis, on the speed of platelet count increase after diagnosis, on concomitant diseases and risk factors for thromboembolic events, and on current treatment, e.g. Hydroxyurea or Interferon a.