Primary immune thrombocytopenia is a potentially life-threatening condition. Approximately two-thirds of adult patients do not have a sustained response to steroids (first-line therapy). For these patients, a number of other treatment options exist, such as rituximab, splenectomy, immunosuppressants, and thrombopoietin receptor agonists, but they are costly and have side effects. Dapsone is an inexpensive drug with a well-established safety profile. Unfortunately, this treatment option has not been explored adequately. This review is aimed at analyzing the currently available evidence for the use of dapsone as second-line or third-line therapy in primary immune thrombocytopenia.