Relugolix and Amiodarone: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 2, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Amiodarone
Relugolix
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
You've been prescribed amiodarone (a heart rhythm medicine) and relugolix (Orgovyx, used to treat prostate cancer). There are two things to know here. First, amiodarone can block a pump in your body called P-gp that normally helps move relugolix out. When that pump is slowed down, more relugolix can build up, which may mean more side effects.
Second, both of these drugs can affect your heart's electrical rhythm (called the QT interval), and together that effect can add up. This is a theoretical concern based on how the drugs work, not a guaranteed problem. The good news is your care team can manage this with careful timing, checking your blood levels of minerals (electrolytes), and heart tracings (ECGs). Never stop either drug on your own, just talk with your doctor or pharmacist.
Effect: Amiodarone (P-gp inhibitor) may increase relugolix (P-gp substrate) exposure, plus additive QT prolongation from both agents. Neither drug is a prodrug, so this is a straightforward exposure increase and PD additive effect.
- Mechanism: Inhibition of P-gp-mediated efflux of relugolix; additive QTc prolongation.
- Direction: Increased relugolix exposure and increased torsades/QT risk.
- Evidence: Theoretical; severity rated major. Note amiodarone's long half-life prolongs the interaction window.
- Management: Avoid if possible. If unavoidable, give relugolix first, separate dosing by at least 6 hours, monitor for adverse reactions. Correct electrolytes; consider periodic ECG and electrolyte monitoring. Weigh benefit of ADT against risk in patients with long QT, CHF, or electrolyte abnormalities.
What happens
Increased relugolix exposure and an increased risk of QT interval prolongation
Interaction Deep Dive
Do not use relugolix (a P-gp substrate) together with P-gp inhibitors, since this combination can raise relugolix exposure and thereby heighten the potential for adverse reactions. When coadministration cannot be avoided, give the relugolix-containing product first, allow a gap of at least 6 hours between doses, and increase the frequency of monitoring for adverse reactions12. Relugolix therapy may be paused for as long as 2 weeks to accommodate a brief course of a P-gp inhibitor. Once the P-gp inhibitor has been stopped, relugolix can be resumed. When relugolix has been withheld for more than 7 days, restart it using a loading dose of 360 mg on day one, then continue at 120 mg once daily 1. Giving relugolix alongside medications that prolong the QT interval can produce additive QT effects. In patients with congenital long QT syndrome, congestive heart failure, or recurrent electrolyte disturbances, as well as those receiving drugs recognized to prolong the QT interval, weigh whether the advantages of androgen deprivation therapy such as relugolix outweigh the possible risks. Correct any electrolyte abnormalities and consider intermittent monitoring of ECGs and electrolytes 1.
Why it happens (mechanism)
Inhibition of P-gp-mediated efflux transport of relugolix; additive QT interval prolongation
How to manage this interaction
Your care team will decide whether these two can be used together, and often they prefer to avoid combining them. If both are needed, here is what is typically done:
- Timing: Take your relugolix first, and separate the two doses by at least 6 hours.
- Monitoring: Your team may check your electrolytes (like potassium and magnesium) and order periodic ECGs to watch your heart rhythm.
- Adjustment: Your regimen may need to be individualized, and dosing may be adjusted by your care team.
Keep taking both exactly as prescribed unless your doctor tells you otherwise. Ask your pharmacist or prescriber before changing anything, and report symptoms like fainting, palpitations, or dizziness right away.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) When relugolix (a P-gp substrate) was given together with erythromycin (a P-gp and CYP3A inhibitor), the AUC and Cmax of relugolix rose by 3.5-fold and 2.9-fold, respectively 1.
Common questions
Can I take Relugolix and Amiodarone together?
Amiodarone can raise relugolix levels and both drugs can prolong the QT interval, so this combination is usually avoided. If you take both, keep them as prescribed and let your doctor manage timing, electrolytes, and ECG monitoring. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Relugolix and Amiodarone interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How is the Relugolix and Amiodarone interaction managed?
Your care team will decide whether these two can be used together, and often they prefer to avoid combining them. If both are needed, here is what is typically done: Timing: Take your relugolix first, and separate the two doses by at least 6 hours. Monitoring: Your team may check your electrolytes (like potassium and magnesium) and order periodic ECGs to watch your heart rhythm. Adjustment: Your r… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Relugolix or Amiodarone need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (2)
- Product Information: ORGOVYX oral tablets, relugolix oral tablets. Sumitomo Pharma America, Inc (per FDA), Marlborough, MA, 2025. DailyMed
- Product Information: MYFEMBREE(R) oral tablets, relugolix, estradiol, norethindrone acetate oral tablets. Myovant Sciences Inc (per FDA), Brisbane, CA, 2021. DailyMed
Keep reading about Amiodarone
Keep reading about Relugolix
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