This accessible paper discusses the possibility of devising a sound method for dosing patients on T4. It shows it isn't possible, and liquid T4 comes nearest to getting to a sound system. However it still comments on getting the "right" TSH whatever that is. In that they fall into exactly the same trap as the problem they are discussing.
REVIEW ARTICLE
Front. Endocrinol., 29 January 2021 | doi.org/10.3389/fendo.2020....
Levothyroxine Therapy in Thyrodectomized Patients
Paolo Miccoli*, Gabriele Materazzi and Leonardo Rossi
Department of Surgical, Medical, Molecular and Critical Pathology, University of Pisa, Pisa, Italy
CONCLUSION
Despite a remarkable commitment by researchers to find a therapeutic scheme able to predict the exact dose of LT4 to be given to patients after a total thyroidectomy, the attempt to reach the precise dosage failed to reach the target in the totality of the cases. It is reasonable to conclude that because most of the schemes show a considerable complexity but do not offer significant advantages in the percentage of patients reaching the expected results, the search for a fully predictive model seems to be an exercise of futility. Nonetheless, these schemes are of great utility to start the replacement therapy approaching the best dosage, but keeping in mind that changes during follow-up can be necessary according to the TSH values that are to be reached in every case.
Finally, data from the review seem to demonstrate that a significant role will be played by the liquid formulation of LT4, mainly for two reasons: first, because its absorption is easier and quicker than the tablet format, and second, it facilitates a more rapid control of TSH in patients with any kind of malabsorption and probably also in patients without this problem.
