Ketamine treatment has shown promising effects for different mental disorders. Yet, little is known on how people who receive ketamine for a psychiatric problem subjectively experience undergoing this intervention. We conducted a systematic literature search to identify relevant qualitative research on the first‐person experience of undergoing ketamine treatment in a psychiatric context. 24 eligible studies were identified and analysed using a thematic meta‐synthesis approach. Three main themes were identified. First, ‘The Ketamine treatment experience can be understood as a three‐stage journey with unique clinical features at each stage’. Second, ‘The subjective experience of acute ketamine treatment is multifaceted and complex’. Third, ‘Ketamine treatment can have different positive effects—but what happens if it does not work?’. In summary, the subjective experience of receiving ketamine treatment for a psychiatric problem can be understood as a journey whereby patients move towards, then undergo, and eventually depart from ketamine. Before treatment, the experiential focus lies on expectations, hopes, and feelings towards the drug. During treatment, the drug's multifaceted psychotropic effects and how they are emotionally appraised become central to experience. Once treatment is finished, the focus is on the presence or absence of clinically relevant effects. The conceptual framework we propose can guide further qualitative research on this topic and aid mental health professionals to better understand the experience of patients who undergo ketamine treatment for a psychiatric problem.