Relugolix and Mavorixafor: 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
Mavorixafor
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.
These two medicines can interact in two ways. Mavorixafor (Xolremdi) can slow down a natural "pump" in your gut that normally helps clear relugolix (Orgovyx) out of your body. When that pump is blocked, more relugolix can build up, which may lead to more side effects.
On top of that, both drugs can affect your heart's rhythm (something called the QT interval). Taking them together may add to that effect. The good news is that this is a theoretical concern, and your care team can manage it. They may space out the doses, watch you more closely, check your heart with an ECG, and keep your electrolytes (like potassium and magnesium) in a healthy range. Please talk with your pharmacist or doctor before changing anything.
Mechanism: Mavorixafor inhibits P-gp-mediated efflux of relugolix (a P-gp substrate), potentially increasing relugolix exposure. Both agents may also contribute additive QT prolongation. Neither is a prodrug; the direction is increased relugolix effect/toxicity.
- Direction/magnitude: Higher relugolix AUC/Cmax; magnitude not quantified.
- Onset: Unspecified. Evidence: Theoretical.
- Management: Avoid coadministration if possible. If unavoidable, give relugolix first, separate by at least 6 hours, and monitor more frequently. Relugolix may be interrupted up to 2 weeks for short P-gp inhibitor courses; if interrupted >7 days, restart with 360 mg loading dose then 120 mg daily.
- QT: Correct electrolytes; consider periodic ECG and electrolyte monitoring, especially with LQTS, CHF, or electrolyte disturbance.
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, in turn, heighten the likelihood of adverse reactions. When the two cannot be avoided together, give the relugolix-containing product first, keep the doses at least 6 hours apart, and increase how often you watch for adverse reactions12. Relugolix therapy may be paused for as long as 2 weeks to allow a brief course of a P-gp inhibitor, with relugolix resumed once the P-gp inhibitor has been stopped. When relugolix has been interrupted for more than 7 days, restart it using a 360 mg loading dose on day one, then continue at 120 mg once daily1. Giving relugolix alongside medications that prolong the QT interval may produce additive QT interval effects. In patients who have congenital long QT syndrome, congestive heart failure, or recurrent electrolyte disturbances, as well as those on drugs recognized to prolong the QT interval, weigh whether the benefits of androgen deprivation therapy such as relugolix are greater than the possible risks. Any electrolyte disturbances should be corrected, and periodic ECG and electrolyte monitoring should be considered1.
Why it happens (mechanism)
Inhibition of P-gp-mediated efflux transport of relugolix; additive QT interval prolongation
How to manage this interaction
Keep taking both exactly as prescribed unless your care team tells you otherwise. Because these can be used together in some situations, your team has clear ways to manage this:
- Timing: If both are needed, relugolix is usually taken first and doses are separated by at least 6 hours.
- Monitoring: Your team may watch you more closely for side effects, check your heart rhythm with periodic ECGs, and monitor and correct electrolytes such as potassium and magnesium.
- Short courses: Relugolix dosing may be paused or restarted with a specific plan by your prescriber.
Ask your pharmacist or doctor before starting, stopping, or spacing these medicines, and report any dizziness, fainting, or palpitations.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) Giving relugolix (a P-gp substrate) together with erythromycin (a P-gp and CYP3A inhibitor) raised relugolix's AUC by 3.5-fold and its Cmax by 2.9-fold, respectively 1.
Common questions
Can I take Relugolix and Mavorixafor together?
Combining mavorixafor and relugolix can raise relugolix levels and add to QT (heart rhythm) risk, so this pairing is generally avoided; if used together, your care team will separate the doses, monitor your ECG and electrolytes, and watch for side effects. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Relugolix and Mavorixafor 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 Mavorixafor interaction managed?
Keep taking both exactly as prescribed unless your care team tells you otherwise. Because these can be used together in some situations, your team has clear ways to manage this: Timing: If both are needed, relugolix is usually taken first and doses are separated by at least 6 hours. Monitoring: Your team may watch you more closely for side effects, check your heart rhythm with periodic ECGs, and m… 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.
Questions for your pharmacist
- Does my dose of Relugolix or Mavorixafor 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 Mavorixafor
Keep reading about Relugolix
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
Check another combination
Our instant two-drug interaction checker is almost here.
Still have questions about this combination?
Every question gets a real answer from a licensed pharmacist — free, and usually within a day.
Ask the pharmacist