Effects of Long-term Combination LT4 and LT3 Therapy for Improving Hypothyroidism and Overall Quality of Life

^aLower TSH in patients with history of thyroid cancer.
FT3, free triiodothyronine; FT4, serum-free thyroxine; LT3, liothyronine; LT4, levothyroxine; TSH, thyroid-stimulating hormone.

Authors and Disclosures

Anam Tariq, DO, Yijin Wert, MS, Pramil Cheriyath, MD, and Renu Joshi, MD

Departments of Internal Medicine, Research and Biostatistical Analysis, and Endocrinology, UPMC Pinnacle Health, Harrisburg, Pennsylvania.

Correspondence to
Dr Anam Tariq, Johns Hopkins Hospital, 1830 E Monument St, 4th Floor, Suite 416, Baltimore, MD 21287. E-mail: tanam1@jhmi.edu. To purchase a single copy of this article, visit sma.org/smj-home. To purchase larger reprint quantities, please contact Reprintsolutions@wolterskluwer.com.

Combination therapy of LT4 and LT3 is an experimental treatment for hypothyroidism and has not been approved for use by the US Food and Drug Administration.
The authors did not report any financial relationships or conflicts of interest.

Sidebar

Key Points

• Even after years of levothyroxine monotherapy, some patients believe that they still have an impaired quality of life.

• The meta-analysis of combination therapy has been negative for combination therapy in managing hypothyroidism, and the data reported on some general well-being questionnaires also are inconclusive.

• Low levels of 25[OH] vitamin D, vitamin B₁₂, and hemoglobin were checked in our study to rule out other causes of fatigue and hypothyroidism before starting combination therapy because they have not been ruled out in previous literature.

• In our population, the symptoms of hypothyroidism improved significantly as reported on follow-up encounters with subsequent improvement in laboratory thyroid function studies and questionnaires, and furthermore, not resulting in hyperthyroidism that caused hospitalizations for medication adverse effects, arrhythmias, or cardiac death.