Frontiers Selenium and thyroid diseases L carnitine supplementation for the management of fatigue in patients with hypothyroidism on levothyroxine treatment: a randomized, double blind, placebo controlled trial. Semantic Scholar Hypothyroidism is a condition where the thyroid gland does not produce enough thyroid hormone which is crucial to regulate the body's metabolism and growth development. There can be various causes that contribute Does L Carnitine help manage hyperthyroidism symptoms? Consensus