To date, systemic treatments, including hormone therapies or chemotherapy, are used at different stages of prostate cancer disease. Several types of complications can occur during systemic treatment in prostate cancer, depending on the therapeutic range. The most common with hormone therapy are fatigue, muscle loss, bone loss, high blood pressure and metabolic syndromes. For chemotherapy, the most significant risk is related to hematological toxicity, but peripheral neuropathies, mucositis, diarrhea and hypersensitivity reactions may also occur. The quality of the pre-treatment assessment and the rigorousness of patient follow-up make it possible to anticipate most of these events, to prevent them or to manage them at an early stage when they occur. The most important aspect is patient education, which involves comprehensive information and the implementation of supportive care as soon as the treatment is initiated. Specialized advice (e. g. cardiological or endocrinological) is recommended in the event of uncontrolled symptomatology. The resumption of treatment leading to a major complication should be the subject of a multidisciplinary discussion taking into account the severity of the event, its reversibility, the patient's life expectancy and the expected efficacy of the molecule.