Cariprazine and Lenacapavir: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 16, 2026 · Source data updated Jul 16, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Lenacapavir
Cariprazine
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.
Here's what's going on. Lenacapavir (Sunlenca or Yeztugo) can slow down a liver enzyme called CYP3A4. That's the same enzyme your body uses to break down cariprazine (Vraylar). When the breakdown slows, more cariprazine and its active form can build up in your body over time. That could mean stronger effects and more side effects, like restlessness, trouble sleeping, dizziness, or unusual movements.
The good news is this is very manageable. Your care team may simply use a lower dose of cariprazine or space it out to every other day while you're on lenacapavir. Please don't change anything on your own. Just check in with your pharmacist or doctor so they can fine-tune your dose.
Mechanism: Lenacapavir inhibits CYP3A4, the primary enzyme metabolizing cariprazine. Cariprazine is an active drug (not a prodrug), so reduced clearance increases exposure to cariprazine and its long-acting active metabolite didesmethylcariprazine (DDCAR), raising AUC and risk of dose-related adverse effects (akathisia, EPS, insomnia).
Evidence: Probable; severity major; onset unspecified (note DDCAR's long half-life delays steady-state changes).
Management (per labeling for a moderate CYP3A4 inhibitor):
- New start: 1.5 mg PO every other day, titrate per response/tolerability.
- On stable 1.5 or 3 mg daily: reduce to 1.5 mg every other day.
- On 4.5 or 6 mg daily: reduce to 1.5 mg once daily.
- If inhibitor discontinued: re-increase cariprazine per response.
What happens
Increased cariprazine and its major active metabolite (didesmethylcariprazine (DDCAR)) exposure
Interaction Deep Dive
Taking cariprazine (which is metabolized by CYP3A4) together with a moderate CYP3A4 inhibitor can raise the levels of both cariprazine and its active metabolite, didesmethylcariprazine. If cariprazine is being started in a patient already receiving a moderate CYP3A4 inhibitor (for schizophrenia or bipolar mania), begin with 1.5 mg orally every other day, and if warranted by clinical response and tolerability, titrate to 1.5 mg orally every other day. For a patient on a moderate CYP3A4 inhibitor being treated for bipolar depression or receiving adjunctive therapy for MDD, the dose is 1.5 mg orally every other day. When a moderate CYP3A4 inhibitor is added for someone already stabilized on cariprazine: for patients currently receiving 1.5 or 3 mg once daily, reduce the cariprazine dose to 1.5 mg orally every other day upon starting the inhibitor; for patients currently receiving 4.5 or 6 mg once daily, reduce the cariprazine dose to 1.5 mg orally once daily upon starting the inhibitor. If the moderate CYP3A4 inhibitor is later stopped, the cariprazine dose may require an increase guided by clinical response and tolerability1.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of cariprazine
How to manage this interaction
What your care team may do: Because lenacapavir can raise cariprazine levels, your prescriber will typically lower or space out your cariprazine dose while you're on both. Documented adjustments include:
- Starting cariprazine low (1.5 mg every other day) if beginning it while on lenacapavir.
- Reducing an existing cariprazine dose (for example, to 1.5 mg every other day, or to 1.5 mg once daily if you were on a higher dose).
- Raising the dose again if lenacapavir is later stopped, based on how you respond.
What you should do: Keep taking both as prescribed, and ask your pharmacist or doctor to confirm your correct cariprazine dose. Report new restlessness, tremor, or trouble sleeping.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) In drug interaction investigations, giving cariprazine 1.5 mg/day together with erythromycin (a moderate CYP3A4 inhibitor) 500 mg twice daily for 21 days led to an increase in cariprazine AUC (0 to 24 hours) and Cmax of roughly 50% 1. In a single study enrolling only White males who received cariprazine 1.5 mg/day and erythromycin 500 mg twice daily (n=40), AUCs rose by 38% (cariprazine), 11% (desmethylcariprazine, an active metabolite), and 60% (didesmethylcariprazine, an active metabolite), while Cmax increased by 34%, 16%, and 62%, respectively. Tmax was unaffected by coadministration with erythromycin 2.
Common questions
Can I take Cariprazine and Lenacapavir together?
Lenacapavir can raise cariprazine levels by slowing its breakdown, so your doctor will likely use a lower or less frequent cariprazine dose while you take both. Keep taking both as prescribed and confirm your dose with your pharmacist or prescriber. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Cariprazine and Lenacapavir 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 Cariprazine and Lenacapavir interaction managed?
What your care team may do: Because lenacapavir can raise cariprazine levels, your prescriber will typically lower or space out your cariprazine dose while you're on both. Documented adjustments include: Starting cariprazine low (1.5 mg every other day) if beginning it while on lenacapavir. Reducing an existing cariprazine dose (for example, to 1.5 mg every other day, or to 1.5 mg once daily if yo… Management is individual — always follow your own care team's guidance.
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 Cariprazine or Lenacapavir 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: VRAYLAR(R) oral capsules, cariprazine oral capsules. AbbVie Inc. (per FDA), North Chicago, IL, 2024. DailyMed
- Szabo M, Hujber Z, Harsanyi J, et al: Coadministration of cariprazine with a moderate CYP3A4 inhibitor in patients with schizophrenia: implications for dose adjustment and safety monitoring. Clin Pharmacokinet 2024; 63(10):1501-1510. PubMed
Keep reading about Lenacapavir
Keep reading about Cariprazine
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