Ketoconazole Topical and Suzetrigine: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Ketoconazole Topical
Suzetrigine
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.
What happens
Increased suzetrigine and M6-SUZ (active metabolite) exposure and an increased risk of suzetrigine-related adverse reactions
Interaction Deep Dive
Concomitant use of suzetrigine (CYP3A substrates) with strong CYP3A inhibitors is contraindicated, as it may increase suzetrigine and M6-SUZ exposures, which may cause suzetrigine-related adverse reactions. In a drug interaction study, concomitant use of itraconazole (a strong CYP3A inhibitor) with a single dose of suzetrigine increased the geometric mean (CI 90%) AUC (0 to inf) of suzetrigine and M6-SUZ by 4.8-fold (4.3-5.4) and 4.4-fold (3.6-5.4), respectively, while the geometric mean (CI 90%) Cmax of suzetrigine increased by 1.5-fold (1.3-1.6) and Cmax of M6-SUZ decreased by 32% (24-39%)1.
Why it happens (mechanism)
Inhibition of CYP3A-mediated metabolism of suzetrigine
Literature reports
1 report — tap to read
a) In a drug interaction study, concomitant use of itraconazole (a strong CYP3A inhibitor) with a single dose of suzetrigine increased the geometric mean (CI 90%) AUC (0 to inf) of suzetrigine and M6-SUZ by 4.8-fold (4.3-5.4) and 4.4-fold (3.6-5.4), respectively, while the geometric mean (CI 90%) Cmax of suzetrigine increased by 1.5-fold (1.3-1.6) and Cmax of M6-SUZ decreased by 32% (24-39%) 1.
Common questions
Can I take Ketoconazole Topical and Suzetrigine together?
Increased suzetrigine and M6-SUZ (active metabolite) exposure and an increased risk of suzetrigine-related adverse reactions Always confirm with your pharmacist or prescriber before making any change.
How serious is the Ketoconazole Topical and Suzetrigine interaction?
It is rated contraindicated. These should generally not be used together.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Ketoconazole Topical or Suzetrigine 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 (1)
- Product Information: JOURNAVX oral tablets, suzetrigine oral tablets. Vertex Pharmaceuticals Inc (per FDA), Boston, MA, 2025. DailyMed
Keep reading about Ketoconazole Topical
Keep reading about Suzetrigine
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