A publication of the American Thyroid Association

Summaries for the Public from recent articles in Clinical Thyroidology

Table of Contents | PDF File for Saving and Printing

A novel, futuristic method of thyroid hormone treatment

CTFP Volume 11 Issue 11


The thyroid gland is responsible for making the thyroid hormones, T3 and T4. Hypothyroidism, or an underactive thyroid, is a common medical condition that requires replacement of the thyroid hormones. Levothyroxine (synthetic T4) is the most commonly prescribed form of thyroid hormone treatment. However, there has been growing interest to understand the risks and benefits of also replacing T3, along with T4, in patients with hypothyroidism as some patients do not feel well on T4 alone. Although more data are needed regarding the potential concerns of T3, it is thought that approximately 5–7% of T3 and 93–95% of T4 may be a safe ratio for those who desire T3. Currently, T3 and T4 treatments are available as either synthetic or animal-derived formulations. The animal-derived products (desiccated thyroid extract) contain approximately 25% T3 and 75% T4 in a single pill. Synthetic T3 and T4 are only available as two separate prescription pills.

Thermal inkjet printing is a form of 2D printing which may have interesting uses within the pharmaceutical industry. It can deliver very precise amounts of a one or more substances through the use of a special type of printing. Thus, it can potentially produce a highly personalized combined single pill of synthetic T4 and T3 (in any desired ratio of the two thyroid hormones). This study reports the potential use of 2D-printed T4 and/or T3 gel films as a novel, futuristic form of personalized thyroid replacement therapy.


Alomari M et al. Printing T3 and T4 oral drug combinations as a novel strategy for hypothyroidism. Int J Pharm 2018 Jul 29;549(1-2):363-369.


This article describes that commonly-used dosages of T4 and/or T3 were able to be successfully printed onto gel films. The amounts of actual T4 and T3 in the gels were fairly close to those being delivered from the inkjets. The gels contained minimal water, and they were stable up to a very high temperature.


This is the first study to report how thyroid hormones may be synthetically produced into a single combined T4+T3 pill using 2D printing. This technology has been reported also for a few other medications in the research setting only. This technology is not yet FDA-approved and has yet to be used commercially on a large scale. However, it is an interesting concept and may offer the ability to titrate thyroid hormone replacement therapy very precisely and in a highly-personalized form of medical therapy.

— Angela M. Leung, MD, MSc


support thyroid research

Hypothyroidism: A condition where the thyroid gland is underactive and doesn’t produce enough thyroid hormone. Treatment requires taking thyroid hormone pills.

Levothyroxine (T4): the major hormone produced by the thyroid gland and available in pill form as Synthroid™, Levoxyl™, Tyrosint™ and generic preparations.

Thyroid hormone therapy: patients with hypothyroidism are most often treated with Levothyroxine in order to return their thyroid hormone levels to normal. Replacement therapy means the goal is a TSH in the normal range and is the usual therapy. Suppressive therapy means that the goal is a TSH below the normal range and is used in thyroid cancer patients to prevent growth of any remaining cancer cells.

Desiccated thyroid extract: thyroid hormone pill made from animal thyroid glands. Currently desiccated thyroid extract is made from pig thyroids and is available as Armour Thyroid™ and Nature-Throid™.

Thyroxine (T4): the major hormone produced by the thyroid gland. T4 gets converted to the active hormone T3 in various tissues in the body.

Triiodothyronine (T3): the active thyroid hormone, usually produced from thyroxine.

Triiodothyronine (T3): the active thyroid hormone, usually produced from thyroxine, available in pill form as Cytomel™.