L-carnitine and thyroid hormone tended to antagonize reciprocally in human body. Urinary excretion of L-carnitine decreased in hypothyroid patients, and levothyroxine supplementation increased excretion of L-carnitine. The investigators hypothesized that supplying L-carnitine to hypothyroid patients with fatigue symptom could improve the quality of life, and fatigue score in them. Therefore, the investigators planned to compare the efficacy of L-carnitine and placebo in hypothyroid patients who had taken levothyroxine.

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study.
To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below.
For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01769157