Clinical insights into levothyroxine overdose: A systematic review

Area of Science:

• Endocrinology
• Clinical Toxicology
• Pharmacology

Background:

• Levothyroxine (LTX) is a widely prescribed medication for hypothyroidism.
• Overdose (OD) of LTX, though infrequent, poses significant clinical risks.
• Limited data exist on LTX OD outcomes and management strategies.

Purpose of the Study:

• To systematically review and synthesize available data on levothyroxine overdose.
• To characterize clinical presentations, management approaches, and patient outcomes in LTX OD.
• To provide a comprehensive dataset for understanding LTX OD.

Main Methods:

• A systematic literature search was performed across PubMed, Scopus, and EMBASE.
• Included English-language articles reporting primary patient data on LTX OD in all age groups.
• Data analysis was conducted using STATA-18.

Main Results:

• Analysis included 49 studies with 95 case reports and 11,513 patients from retrospective studies.
• Common symptoms included tachycardia, confusion, and fever; severe complications like atrial fibrillation were rare.
• Intentional OD cases were older and had higher diastolic blood pressure; accidental OD cases had higher heart rates.
• Most patients, especially children, experienced minimal symptoms; severe outcomes were rare and primarily in adults with high-dose ingestions.

Conclusions:

• This study presents the first comprehensive dataset on levothyroxine overdose.
• Demographics of LTX OD differ: pediatric for accidental, adult for intentional cases.
• While high-dose LTX ingestion carries toxicity risks, mortality is exceptionally rare.