Fig. 2

Levothyroxine dose titration flowchart. Levo-thyroxine dose is increased/decreased by 25 μg with a maximum dose of 150 μg. TSH checked 6–8 weeks after every dose change until TSH is within the reference range of 0.4–4.6 mU/L. If TSH is found to be ≥20 mU/L, a second TSH (and fT4) measurement is taken within 2 weeks. If a TSH of ≥20 mU/L is confirmed at second measurement then the patient is required to stop the trial medication and attend GP for further investigation