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January 1992

Evidence for Interference With the Intestinal Absorption of Levothyroxine Sodium by Aluminum Hydroxide

Author Affiliations

From the Institute of Gastroenterology (Dr Sperber) and the Endocrinology Service (Dr Liel), Division of Internal Medicine, Soroka Medical Center and the Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel. Dr Sperber is currently at the School of Public Health, University of North Carolina at Chapel Hill.

Arch Intern Med. 1992;152(1):183-184. doi:10.1001/archinte.1992.00400130181024

A patient with hypothyroidism who was euthyroid on a fixed-dosage, long-term maintenance regimen of levothyroxine sodium developed persistently elevated serum thyrotropin levels while receiving an aluminum hydroxide— containing antacid. The thyrotropin levels returned to normal shortly after cessation of the antacid therapy. These observations indicate that aluminum hydroxide may interfere with the bioavailability of thyroxine. The thyroid function of patients who are receiving replacement or suppressive thyroxine therapy should be monitored following the commencement of concurrent treatment with medications containing aluminum hydroxide.

(Arch Intern Med. 1992;152:183-184)

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