Clinical insights into levothyroxine overdose: A systematic review

BACKGROUND: Levothyroxine (LTX) is one of the most commonly used medications due to the high prevalence of hypothyroidism in various age groups. Overdose (OD) with LTX, intentional or unintentional, is rare but can have clinically significant and even life-threatening consequences. Data on clinical outcomes of patients with LTX OD are limited, and guidelines on its management are suboptimal. AIM: To compile all available data on the clinical characteristics, management, and outcomes of patients with LTX OD. METHODS: A systematic literature search was conducted to identify English-language articles through PubMed, Scopus, and EMBASE that reported primary patient data on LTX OD in all age groups. All analyses were performed using STATA-18. RESULTS: = 0.02). Among the 11513 patients from larger studies, more than 90% experienced minimal or no symptoms, particularly in pediatric cohorts. Rarely severe outcomes, such as coma and cardiac failure, were observed in adults with high-dose ingestions, requiring interventions such as beta-blockers, corticosteroids, and plasmapheresis. CONCLUSION: This study provides the first comprehensive dataset on LTX OD. Patients with non-suicidal/accidental LTX OD mainly belong to the pediatric age group, while those with suicidal intent belong to the older age group. Despite the risk of toxicity with ingestion of high doses of LTX, mortality is extremely rare.