Idiopathic thrombocytopenic purpura (ITP) is an acquired haematologic disorder, common among children and adults, with unknown etiology and autoimmune pathogenesis. Nowadays, appropriate diagnostic and treatment strategies are still uncertain; therefore, the attending physicians behaviour in front of thrombocytopenic patients remains heterogeneous. Through a Medline research, we selected eighteen scientific works with practical application. Some of these studies tried to settle the diagnostic-therapeutic approach to thrombocytopenic patient by adopting specific guidelines developed by skilled medical panels. In this review we describe the main features of ITP in adults, in children and pregnant women and we also synthetize the diagnostic-therapeutic behaviours for which there is a sufficient agreement in order to standardize ITP patients management reducing unsuitable diagnostic tests and therapies and the costs too.