Found this not sure if it has appeared on here before ... onlinelibrary.wiley.com/doi...
Most patients respond satisfactorily within weeks of therapy, with striking improvement in typical symptoms. However, some levothyroxine-treated individuals continue to experience persistent symptoms despite adequate biochemical correction.4-7 The optimal approach to the management of such individuals remains controversial, largely because our understanding of why such patients have persistent symptoms remains poor. While a few practitioners would offer alternative thyroid therapies such as liothyronine and desiccated thyroid extracts (DTE) to such individuals, others would opt for an approach that is primarily focused on addressing lifestyle, alternative physical health-related or psychosocial explanations for persistent morbidity.8 These different approaches are based on the failure of numerous randomised controlled trials (RCT) to show the superiority of combination liothyronine/levothyroxine therapy over levothyroxine monotherapy alone9-12 (discussed below).