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📈 QT Prolongation Risk & High-Risk Drugs

UseBedside risk awareness before prescribing QT-prolonging agents. Look up authoritative per-drug ratings at Cre…

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SourceCredibleMeds (AZCERT) QTdrugs lists

Runs locally in your browser (no PHI uploaded). For licensed clinicians — not a substitute for clinical judgement.
Stored on this device for revisit reminders

This-shift next steps

After scoring: open the scene pack, peer scores, and the matching pathway. Local reference — no HIS write.

Scene next step
📋med safetyOpen scene pack →
Related scores
Score + version; reference only — not a substitute for care · no HIS write

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Methodology · worked example, guidelines & full notes
Clinical takeaway

Risk multiplies when drug, electrolyte and patient factors stack.

When to use

Bedside risk awareness before prescribing QT-prolonging agents. Look up authoritative per-drug ratings at CredibleMeds; compute the QTc value with this site's QTc tool.

How it works

Prolonged: men > 450 ms, women > 470 ms. High-risk: QTc > 500 ms or +60 ms from baseline. Keep K⁺ > 4.0 mmol/L and Mg²⁺ > 2.0 mg/dL.

Key points

  • Risk multiplies when drug, electrolyte and patient factors stack.
  • Correcting hypokalaemia/hypomagnesaemia and bradycardia markedly lowers TdP risk.
  • Treat TdP with IV magnesium; consider pacing/isoprenaline.
  • Avoid combining multiple QT-prolonging drugs.

References

Worked calculation

The values below come from this tool's own example placeholders and are computed server-side with the formula shown on this page, so the arithmetic can be checked quickly. It demonstrates how to substitute values only — it is not clinical advice and not a real case.

ViewModifiable risk factors

→Quick referenceModifiable risk factors

  • Electrolytes：Hypokalaemia, hypomagnesaemia, hypocalcaemia
  • Heart rate：Bradycardia, long pause / post-pause
  • Drug stacking：Multiple QT-prolonging drugs; CYP inhibition raising levels
ViewHigh-risk drug classes

→Quick referenceCommon QT-prolonging drug classes

  • Antiarrhythmics IA/III：Quinidine, procainamide, disopyramide; sotalol, amiodarone, dofetilide, ibutilide
  • Macrolides：Erythromycin, clarithromycin, azithromycin
  • Fluoroquinolones：Moxifloxacin > levofloxacin > ciprofloxacin
Verification & sources · governance
FAQ

Frequently asked questions

What are the limits and cautions when using QT Prolongation Risk & High-Risk Drugs?
For licensed clinicians and clinical researchers. Interpret results with history, investigations and local protocols; not a diagnosis or prescription, and not a substitute for multidisciplinary decision-making or local guidelines.
Does QT Prolongation Risk & High-Risk Drugs upload patient data? Where is it calculated?
Calculation runs locally in the browser; inputs and results are not uploaded. For licensed clinicians only; interpret with history, investigations and local protocols — not a diagnosis or prescription.
How is QT Prolongation Risk & High-Risk Drugs calculated in practice? Can you show a worked example?
Inputs: View Modifiable risk factors → Result: Quick reference Modifiable risk factors（Electrolytes: Hypokalaemia, hypomagnesaemia, hypocalcaemia, Heart rate: Bradycardia, long pause / post-pause, Drug stacking: Multiple QT-prolonging drugs; CYP inhibition raising levels） Inputs: View High-risk drug classes → Result: Quick reference Common QT-prolonging drug classes（Antiarrhythmics IA/III: Quinidine, procainamide, disopyramide; sotalol, amiodarone, dofetilide, ibutilide, Macrolides: Erythromycin, clarithromycin, azithromycin, Fluoroquinolones: Moxifloxacin > levofloxacin > ciprofloxacin）
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