QT_c Screening When Prescribing Methadone: Practice Guideline

Methadone lowers drug-related morbidity and mortality for patients with opioid dependence, and only one other similarly efficacious treatment (namely, buprenorphine, for some patients) exists. But methadone prolongs the rate-corrected QT interval (QT_c) in about 2% of patients, and this condition can result in torsade de pointes. QT_c prolongation is more common at higher doses (>100 mg daily) but can occur at much lower doses; the incidence of methadone-related torsade de pointes is unknown.

This side effect is stated in a recently added black-box warning, but prescribers are largely unaware of the association. The federal Center for Substance Abuse Treatment convened an expert panel to synthesize evidence and formulate practice guidelines on…