The ketamine breakthrough: a new paradigm in the treatment of depression and pain Tharcila Chaves University of Groningen, The Netherlands The proposed presentation aims to acknowledge the cutting-edge and avant-garde properties of ketamine as a tool to treat persistent physical and mental pains. The rapid antidepressant effect of the well-known anaesthetic drug ketamine in patients with treatment-resistant depression (TRD) is considered the most important advance in the pharmacotherapy of depression in 50 years. Depression has surpassed HIV/AIDS, malaria, diabetes and war as the leading cause of disability worldwide. A single dose of ketamine alleviates depressive symptoms within minutes in patients who have failed to respond to two or more conventional antidepressants and these effects are sustained for one week to months. Ketamine is also effective for bipolar depression, it decreases suicidal ideation and has shown positive results in the treatment of other mental conditions, such as post-traumatic stress disorder (PTSD) and obsessivecompulsive disorder (OCD). Furthermore, ketamine has shown antidepressant effects even in patients who do not respond to electroconvulsive therapy. In the management of pain, ketamine’s role as a safe and effective strategy for treating acute pain in emergency departments has recently been expanding; it is also beneficial for treating chronic pain of different origins. However, in Europe, ketamine is still not approved for psychiatric or analgesic uses, although its off-label use, i.e. using it for different purposes than anaesthesia, is increasingly common in the medical setting. In order to treat patients who are refractory to treatment, health professionals are claiming compassionate reasons in order to obtain authorisation to use ketamine as an antidepressant and/or analgesic. In the United States, the ketamine clinics are increasingly popular, indicating that there is an urgent need for rapid-onset antidepressants for TRD and suicidality. Despite the palliative care and rehabilitation that are usually connected with pharmacotherapy in the treatment of chronic pain, 38% of the patients report not being satisfied with their treatments. Hence the need to assist those patients who do not find a way to deal with their condition. Undoubtedly, there is still a lot to be explored about the effects of ketamine in the human body and consciousness. But it is not a reason to ignore the fact that ketamine has the potential to help several people now, with the knowledge that we already have. The failure of conventional therapies and the rise of the ketamine clinics might be the beginning of a new paradigm in mental and physical pain managements.