We think patients who have been shown to have a clinical need for liothyronine should be able to access it on the NHS. We are committed to providing information to support patients with a clinical need for it to access it, as well as supporting research to answer unsolved questions about T3’s effectiveness and long-term safety.

Unfortunately, some patients continue to experience ongoing symptoms even when the results of their blood tests show they are on the correct dose of levothyroxine. Where other causes of symptoms have been ruled out, these patients should be referred to see an NHS endocrinologist for further investigation and to see whether they might benefit from a trial of T3/T4 combination therapy.  

The massive price hikes in T3, for which the companies responsible have now been fined almost £100 million, led to a scandalous situation in which some patients who were doing well on liothyronine were taken off it, while others have been unable to have a trial of it due to their local Integrated Care Board not allowing it to be prescribed based on cost. Indeed, the BTF visited Westminster together with other charities to represent patient views and raise awareness of the issue with members of the House of Lords. 

The BTF works with other UK patient charities to help patients who may benefit from T3 to obtain it fairly, consistently and based on clinical need. We have also helped write clear patient information about the use of T3 and regularly provide support and guidance to patients who have a clinical need for T3 to access it. You can read more at: https://www.btf-thyroid.org/patient-leaflet-about-use-of-liothyronine-t3-in-hypothyroidism

However, T3 remains a controversial treatment and many doctors do not currently prescribe it as the research in this area is mixed.  While some studies show evidence of symptomatic benefit, others have found no added benefit of T3.

We believe more research is the best way to establish conclusive evidence about its effectiveness and safety. Through our BTF Research Award we have funded some ongoing research about the long-term safety of T3. This is taking place at the University of Cardiff and called the ‘Morbidity And Mortality in Liothyronine Treated Patients: LT3 Outcome Study’ Along with other UK patient groups, we are also supporting a large new (Cardiff-based) research trial which will help improve understanding of the safety and benefits of using T3 as a treatment for patients with hypothyroidism. We keenly await the results of these studies which we think offer potential to advance treatment options for patients in the UK and around the world.

Date: June 2025