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Refractory Stable Angina

Ranolazine

Brand names: Ranexa

Ranolazine is an add-on anti-anginal for chronic stable angina, used when symptoms are inadequately controlled by, or the patient cannot tolerate, first-line therapy.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

500 mg twice daily and increase to 1000 mg twice daily, based on clinical symptoms ( 2.1 ) 2.1 Dosing Information Initiate ranolazine extended-release tablet dosing at 500 mg twice daily and increase to 1000 mg twice daily, as needed, based on clinical symptoms. Take ranolazine extended-release tablet with or without meals. Swallow ranolazine extended-release tablet whole; do not crush, break, or chew. The maximum recommended daily dose of ranolazine extended-release tablet is 1000 mg twice daily. If a dose of ranolazine extended-release tablet is missed, take the prescribed dose at the next scheduled time; do not double the next dose. 2.2 Dose Adjustments in Specific Populations Dose …

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2026-01-29. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Clinical monograph

How it works

It inhibits the late inward sodium current in cardiac myocytes, reducing intracellular sodium and calcium overload and so improving myocardial relaxation and oxygen efficiency, with little effect on heart rate or blood pressure.

Prescribing in practice

  • It prolongs the QT interval, so avoid combining with other QT-prolonging drugs and use caution in patients at risk of QT prolongation.
  • It is a CYP3A4 substrate with many interactions; avoid strong CYP3A4 inhibitors and review concomitant medicines before starting.
  • Use is restricted or contraindicated in significant renal or hepatic impairment, so check renal and liver function before initiation.

Monitoring

Review renal and hepatic function and concurrent medicines before and during treatment; consider ECG monitoring of the QT interval where clinically indicated.

Counselling the patient

  • Tell any prescriber or pharmacist you take ranolazine before starting new medicines, as interactions are common.
  • Avoid grapefruit juice, which can raise the drug level.
  • Report palpitations, fainting or dizziness.

Evidence & guidelines

Recommended as an add-on option for stable angina when first-line drugs are insufficient or not tolerated (NICE NG185).

Reference: MERLIN-TIMI 36 Trial (Morrow et al. JAMA 2007); ESC Stable CAD Guidelines 2019; NICE CG126; SPC Ranexa; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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