We read with interest the study by Ehret and colleagues1 suggesting that clinically significant QTc interval prolongation (>500 milliseconds) occurred in over 16% of hospitalized patients receiving methadone. In practice, this probably overestimates the expected frequency of QTc prolongation with methadone use, given the authors’ exclusion criteria, but nonetheless suggests that considerable QTc prolongation with methadone use is probably not a rare phenomena.
Schmittner J, Krantz MJ. QTc Prolongation Among Hospitalized Patients Receiving Methadone. Arch Intern Med. 2006;166(20):2289. doi:10.1001/archinte.166.20.2289-a