Chronic fatigue syndrome (CFS), or myalgic encephalomyelitis, is a controversial enigmatic illness. While there is no known cause of CFS, there is some contest between researchers, about how best to conceive and explain CFS. However, while aetiology and pathophysiology remain unclear, there is robust qualitative and quantitative research from a range of countries that doctors and medical students display persistent uncertainty about whether CFS is a real physical illness. The evidence shows that clinicians treat CFS patients with suspicion and adopt primarily psychological interventions for this unexplained physical illness. What is striking in CFS, which signals this illness out for attention, is that many CFS patients reject the psychogenic model of their illness and a significant number report feeling distressed or harmed by their interactions with doctors. Against this background, we address the neglected and important issue of the ethical treatment of patients with CFS framed against Miranda Fricker’s concepts of testimonial and hermeneutic injustice (2007). We find evidence to support the contention that the discursive exchange between doctors and CFS patients is one forum where epistemological injustices appear to exist. In this paper we argue that CFS patients’ reports of injustice and acrimony represent the often unintentional consequences of medical iatrogenesis that emerge where doctors formulate and apply medical models, with associated interventions, that create or enhance suffering or distress and fail to fully incorporate the patient narrative and perspective.