How do you approach a patient maintained on chronic methadone incidentally found to have a prolonged QTc?

If a patient without OUD on chronic methadone who has not previously had QTc issues, suddenly has a prolonged QTc, I look for other reversible causes such as hypokalemia, hypomagnesemia, new medications (such as recent antibiotics, Zofran), etc. From there, it's a nuanced and patient-centered risk/b...