Charcoal Hemoperfusion in the Treatment of Levothyroxine Intoxication

Background: Levothyroxine ( l -thyroxine) intoxication may arise from intentional or accidental ingestion of excessive doses of the hormone and may cause symptoms equivalent to thyroid storm. We report a case of massive accidental l -thyroxine intoxication resulting from an error in the preparation of capsules to treat goiter. Summary: A 61-year-old woman was admitted showing high levels of thyroid hormones, with serum-free l -thyroxine level of 955.90 nmol/L (74.1 ng/mL) (normal values: 11.61–27.09 nmol/L or 0.9–2.1 ng/mL). It was discovered that she had ingested 50 mg instead of 50 μg/day of l -thyroxine during 9 days. Following charcoal hemoperfusion, the levels of total thyroxine, serum-free l -thyroxine, and triiodothyronine declined dramatically, with a reproducible pattern of reduction in hormone levels observed after each of the three sessions. The patient recovered from her stuporous mental state, atrial fibrillation, and acute respiratory failure. Conclusion: The use of hemoperfusion with a charcoal filter appears to be a very important therapeutic tool for the treatment of acute and severe forms of thyrotoxicosis due to l -thyroxine intoxication.