Critical
Droperidol × Methadone
First-generation antipsychotic, butyrophenone. Used as antiemetic.×Synthetic opioid, full mu-receptor agonist
Mechanism
Dual QT prolongation, especially with methadone above 80 mg/day.
Symptoms
QTc above 500 ms, syncope, torsades de pointes risk.
Management
Combination contraindicated.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.
Sources
- FDA: Inapsine (droperidol) prescribing information (2007)– FDA Inapsine label, boxed warning QT