Major
Chlorpromazine × Moxifloxacin
First-generation antipsychotic, aliphatic-side-chain phenothiazine×Fourth-generation fluoroquinolone
Mechanism
Additive QT prolongation.
Symptoms
QTc above 500 ms, syncope, torsades de pointes risk.
Management
Alternative – levofloxacin.
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: Thorazine (chlorpromazine) prescribing information (2014)– FDA Thorazine label