Date of Award
2026
Document Type
Capstone
Degree Name
Master of Science (MS)
Department
Physician Assistant Studies
Committee Chair
Trey Boyd
Abstract
Introduction: Primary hypothyroidism is a common condition where the thyroid gland cannot produce free thyroxine (T4), leading to low serum levels of it. For this reason, it is often treated directly with monotherapy synthetic T4 or as a combined synthetic T4/T3. The purpose of this clinical review is to analyze the effectiveness of T4 monotherapy versus T4/T3 combination therapy in normalizing TSH values and improving symptoms in adults with hypothyroidism.
Methods: A specific search strategy in PubMed was used to conduct the research, incorporating key terms such as “hypothyroidism,” “levothyroxine,” “liothyronine,” and “TSH.” Four quality articles were left for final review after filters and operators dwindled them down from a list of 58 articles.
Results: One article was a randomized controlled trial (RCT) directly comparing LT4/LT3 and LT4 monotherapy. Another article was a systematic review of studies comparing these treatment regimens, while two articles were systematic reviews and meta-analyses comparing the same therapies as well.
Discussion: The articles had a general conclusion that there was no benefit in LT4/LT3 combined therapy versus monotherapy. However, these generalizations do not discuss the findings that combined therapy aided in some specific symptom alleviation, along with being the patient’s preferred treatment. Therefore, further research is needed.
Recommended Citation
Thomas AF. Monotherapy versus Combination Levothyroxine and Liothyronine in the Treatment of Hypothyroidism. The PA Department Journal of Medical Science. 2025. https://digitalcommons.gardner-webb.edu/pa-department-journal-of-medical-science/53
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