Relugolix and Vilanterol: 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
Relugolix
Vilanterol
No brand names on record
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 relugolix (Orgovyx) for prostate cancer and vilanterol, an inhaled breathing medicine. Both of these can, on their own, have a small effect on your heart's electrical rhythm, causing what's called QT prolongation. When taken together, those effects can add up and slightly raise the chance of an irregular heartbeat.
The good news is that this is a possible risk based on theory, not something that happens to everyone. Your care team can manage it easily, often by keeping an eye on your heart rhythm and blood minerals like potassium and magnesium. Please don't stop either medicine on your own. Just talk with your pharmacist or doctor so they can watch this for you.
Effect: Additive risk of QT interval prolongation with concomitant relugolix and vilanterol. Neither drug is a prodrug; this is a pharmacodynamic, not metabolic, interaction.
- Mechanism: Androgen deprivation from GnRH antagonist (relugolix) can prolong QT; beta-2 agonists (vilanterol) also carry QT-prolonging and hypokalemic potential. Effects are additive.
- Evidence: Theoretical. Severity: Major. Onset: Unspecified.
- Management: Weigh benefit of ADT against risk in patients with congenital long QT, CHF, or electrolyte abnormalities. Avoid combination when feasible. If used together, correct and maintain normal K+ and Mg2+, avoid additional QT-prolonging or hypokalemia-inducing agents, and consider periodic ECG and electrolyte monitoring.
What happens
Increased risk of QT interval prolongation
Interaction Deep Dive
When relugolix is given together with medications that prolong the QT interval, the effects on the QT interval are additive. The androgen deprivation produced by GnRH agonists and antagonists can itself lengthen the QT interval. In patients who have 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 hazards1. Whenever feasible, do not use relugolix concurrently with QT prolonging agents. Should coadministration be necessary, steer clear of drugs that produce electrolyte abnormalities (that is, hypokalemia or hypomagnesemia)2, correct any electrolyte abnormalities, and consider periodic monitoring of ECGs and electrolytes1.
Why it happens (mechanism)
Additive QT interval prolongation
How to manage this interaction
Both medicines can nudge your heart rhythm in the same direction, so your care team may take a few simple precautions.
- Keep taking both as prescribed unless your doctor tells you otherwise.
- Your team may check periodic ECGs (heart tracings) and blood levels of potassium and magnesium, since low levels can add to the risk.
- They will try to avoid other medicines that lower these minerals or affect the QT interval.
- Tell your pharmacist or doctor if you have a history of heart rhythm problems, heart failure, or a family history of long QT syndrome.
Report symptoms like fainting, dizziness, or a pounding or irregular heartbeat right away.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) A study examined male patients undergoing androgen deprivation therapy (ADT) using individual case safety reports from VigiBase, the international pharmacovigilance database, and identified 184 cases of acquired long-QT syndrome (aLQTS) and/or torsades de pointes (TdP; 11% of cases fatal), along with 99 cases of sudden death linked to ADT. The majority of aLQTS/TdP cases (62%) and sudden death cases (88%) related to ADT arose in the absence of exposure to other agents known to elevate TdP risk; nevertheless, exposure to 1 drug and to 2 or more drugs carrying conditional, possible, or known TdP risk was documented in a portion of aLQTS/TdP events (23% or 43%) and sudden death events (18% and 22%). The agents classified as ADTs included abiraterone, gonadotropin-releasing hormone agonists and antagonists, nonsteroidal androgen receptor inhibitors indicated for prostate cancer, and 5-alpha-reductase inhibitors indicated for androgenic alopecia and prostatism. Among the 10 ADTs assessed, 7 showed a disproportional association (reporting odds ratio, 1.4 to 4.7) with aLQTS, TdP, or sudden death, namely leuprorelin, goserelin, triptorelin, degarelix, bicalutamide, finasteride, and dutasteride. Patients had a median age of approximately 76 years, and the median time to onset was 170 days (range, 7 to 4884 days) for aLQTS/TdP events and 92 days (range, 0.25 to 4984 days) for sudden death events. Patients were receiving ADT chiefly for prostate cancer, with some treated for prostatism and androgenic alopecia. Most patients received ADT as monotherapy (83%); 17% were on ADT combination therapy 3.
Common questions
Can I take Relugolix and Vilanterol together?
Relugolix and vilanterol can each affect heart rhythm, and together the effect may add up. Keep taking both as prescribed and ask your care team whether periodic heart-rhythm and electrolyte checks are right for you. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Relugolix and Vilanterol 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 Vilanterol interaction managed?
Both medicines can nudge your heart rhythm in the same direction, so your care team may take a few simple precautions. Keep taking both as prescribed unless your doctor tells you otherwise. Your team may check periodic ECGs (heart tracings) and blood levels of potassium and magnesium, since low levels can add to the risk. They will try to avoid other medicines that lower these minerals or affect t… 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 Vilanterol 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 (3)
- Product Information: ORGOVYX oral tablets, relugolix oral tablets. Sumitomo Pharma America, Inc (per FDA), Marlborough, MA, 2025. DailyMed
- Lyon AR, Lopez-Fernandez T, Couch LS, et al: 2022 ESC guidelines on cardio-oncology developed in collaboration with the European Hematology Association (EHA), the European Society for Therapeutic Radiology and Oncology (ESTRO) and the International Cardio-Oncology Society (IC-OS). Eur Heart J 2022; 43(41):4229-4361.
- Salem JE, Yang T, Moslehi JJ, et al: Androgenic effects on ventricular repolarization: a translational study from the international pharmacovigilance database to iPSC-cardiomyocytes. Circulation 2019; 140(13):1070-1080. PubMed
Keep reading about Relugolix
Keep reading about Vilanterol
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