Clinical Resources
Drug QTc Safety Check
QT-Prolonging Medications — Risk Categories & QTc Thresholds
Search by drug name or filter by class. Find the QTc threshold for each agent, then use the Corrected QT calculator to measure the patient's current QTc.
Known Risk — directly prolongs QT; dose-dependent TdP risk
Possible Risk — QT prolongation reported; lower TdP evidence
Conditional Risk — risk emerges with drug interactions, overdose, or in at-risk patients
Showing all 50 drugs
| Drug | QT Risk | Stop / Hold if QTc ≥ |
|---|
Corrected QT Interval Calculator →
Calculate QTc using Bazett, Fridericia, Framingham, Hodges, or Rautaharju — then compare to the threshold above.
Important Cautions
- Baseline QTc: Obtain a 12-lead ECG before initiating any QT-prolonging drug and at steady state.
- Drug combinations: Two or more QT-prolonging drugs dramatically increase TdP risk — especially combinations of antiarrhythmics + antibiotics + antipsychotics.
- Risk factors: Female sex, hypokalemia, hypomagnesemia, bradycardia, heart failure, and structural heart disease all amplify risk.
- Thresholds shown are commonly cited clinical decision points. Always consult current product labeling and institutional guidelines.
References
CredibleMeds QTDrugs List — Arizona CERT / American Heart Association.
Drew BJ et al. (2010) — Prevention of Torsade de Pointes in Hospital Settings. Circulation. 121:1047–1060.