Asenapine and Relugolix: 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
Asenapine
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 asenapine (Saphris or Secuado) and relugolix (Orgovyx). Both of these medicines can affect your heart's electrical rhythm in a similar way, causing something called QT prolongation. When two medicines that do this are taken together, the effect can add up, which in rare cases could lead to an irregular heartbeat.
The good news is this is a known, manageable situation. Your care team may check your heart rhythm with an ECG and keep an eye on your blood minerals like potassium and magnesium. Please keep taking both medicines as prescribed, and let your pharmacist or doctor know if you feel dizzy, faint, or notice a fluttering heartbeat.
Effect: Additive QT interval prolongation with concurrent asenapine (antipsychotic, known QT effect) and relugolix (GnRH antagonist; androgen deprivation itself prolongs QT).
- Direction/mechanism: Pharmacodynamic (PD) additive QTc prolongation, not a metabolic (PK) interaction. Neither agent is relevant as an activating substrate here.
- Severity/evidence: Major; theoretical.
- Onset: Unspecified.
- Management: Avoid combination when feasible. Assess risk/benefit in congenital long QT, CHF, or recurrent electrolyte disturbance. If coadministered, correct and maintain normal K+ and Mg2+, avoid other QT-prolonging or electrolyte-depleting agents, and consider periodic ECG and electrolyte monitoring.
What happens
Increased risk of QT interval prolongation
Interaction Deep Dive
When relugolix is given alongside 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 individuals 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 are greater than the possible risks1. Where feasible, refrain from using relugolix together with QT prolonging agents. Should coadministration be necessary, steer clear of medications that produce electrolyte disturbances (that is, hypokalemia or hypomagnesemia)2, correct any electrolyte abnormalities, and consider intermittent monitoring of ECGs and electrolytes1.
Why it happens (mechanism)
Additive QT interval prolongation
How to manage this interaction
Both drugs can lengthen the QT interval, so your team's goal is to watch your heart and keep it safe.
- Keep taking both as prescribed unless your prescriber tells you otherwise.
- Your team may run periodic ECGs and check electrolytes (potassium and magnesium), correcting any that are low.
- They will weigh the benefits of therapy against the risks, especially if you have a heart rhythm condition, heart failure, or frequent electrolyte problems.
- Tell your pharmacist or doctor about any fainting, palpitations, or dizziness, and about all other QT-affecting medicines you take.
Your care team can manage this by tailoring treatment and monitoring you more closely.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) A study assessing male patients on androgen deprivation therapy (ADT) using individual case safety reports from VigiBase, the international pharmacovigilance database, identified 184 cases of acquired long-QT syndrome (aLQTS) and/or torsades de pointes (TdP; 11% fatal cases), along with 99 cases of sudden death linked to ADT. The majority of aLQTS/TdP cases (62%) and sudden death cases (88%) associated with ADT arose without exposure to other agents known to raise TdP risk; nonetheless, exposure to 1 drug and to 2 or more drugs at conditional, possible, or known TdP risk was documented in some aLQTS/TdP events (23% or 43%) and sudden death events (18% and 22%). The agents regarded 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. The median patient age was 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 taking ADT mainly for prostate cancer treatment, with some receiving therapy for prostatism and androgenic alopecia. Most patients were on ADT monotherapy (83%); 17% were on ADT combination therapy 3.
Common questions
Can I take Asenapine and Relugolix together?
Taking asenapine and relugolix together can add up to prolong the QT interval, so your care team may monitor your ECG and electrolytes; keep taking both as prescribed and report any fainting or palpitations. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Asenapine and Relugolix 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 Asenapine and Relugolix interaction managed?
Both drugs can lengthen the QT interval, so your team's goal is to watch your heart and keep it safe. Keep taking both as prescribed unless your prescriber tells you otherwise. Your team may run periodic ECGs and check electrolytes (potassium and magnesium), correcting any that are low. They will weigh the benefits of therapy against the risks, especially if you have a heart rhythm condition, hear… 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 Asenapine or Relugolix 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 Asenapine
Keep reading about Relugolix
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