Thyroid Dysfunction and Quality of Life in Patients on Lithium Therapy: A Narrative Review

Abstract

Introduction. Lithium remains the gold standard in the treatment of bipolar disorder (BD); however, its narrow therapeutic index and effects on the thyroid gland pose a significant therapeutic challenge and require systematic monitoring for adverse effects.

Aim of the study. To analyze the mechanisms of thyroid dysfunction induced by long-term lithium therapy and evaluate patient monitoring strategies to optimize treatment safety and quality of life (QoL).

Material and methods. A structured narrative review of the medical literature published between 2021 and 2026.

Results. Lithium inhibits iodine uptake and thyroid hormone release, most commonly causing hypothyroidism. Symptoms such as fatigue, weight changes, and cognitive impairment significantly affect daily functioning and may overlap with depressive episodes in BD, substantially reducing QoL.

Conclusions. Appropriate monitoring, diagnostic evaluation, and timely intervention are essential for minimizing complications. Patient education and interdisciplinary collaboration between psychiatrists and endocrinologists are key to maintaining QoL during lithium therapy, underscoring the need to integrate thyroid monitoring into routine psychiatric and endocrinological care.