Itraconazole and Cariprazine: 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
Itraconazole
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.
Itraconazole can make cariprazine (Vraylar) build up in your body. Itraconazole is a strong antifungal that slows down a liver enzyme (called CYP3A4) that normally breaks cariprazine down. When that enzyme is blocked, both cariprazine and its active form can roughly double in your blood.
That means you could feel more of cariprazine's effects and side effects, like sleepiness, restlessness, dizziness, or muscle stiffness. The good news is this is very manageable. Do not stop or change either medicine on your own. Your doctor or pharmacist can lower your cariprazine dose or space it out, and watch how you're doing while you take both.
Mechanism: Itraconazole is a strong CYP3A4 inhibitor; cariprazine is a CYP3A4 substrate. Inhibition reduces clearance, increasing exposure to cariprazine and its active metabolite didesmethylcariprazine.
Magnitude: With ketoconazole, cariprazine AUC and Cmax rose ~100%. Evidence: probable. Direction: increased effect/toxicity risk (extrapyramidal symptoms, akathisia, sedation).
- New start with a strong inhibitor (schizophrenia/bipolar mania): 1.5 mg every 3 days, may increase to 1.5 mg every other day per response.
- Bipolar depression / adjunct MDD: 1.5 mg every 3 days.
- Stable 1.5 or 3 mg daily then add inhibitor: reduce to 1.5 mg every 3 days.
- Stable 4.5 or 6 mg daily: reduce to 1.5 mg every other day.
- On inhibitor discontinuation, cariprazine dose may need to be increased.
What happens
Increased exposure to cariprazine and its active metabolite, didesmethylcariprazine
Interaction Deep Dive
When cariprazine (a CYP3A4 substrate) is given together with a potent CYP3A4 inhibitor, the exposure to cariprazine as well as its active metabolite didesmethylcariprazine may rise. In drug interaction studies, giving cariprazine alongside ketoconazole (a strong CYP3A4 inhibitor) produced an increase of roughly 100% in both AUC and Cmax. For this reason, when cariprazine therapy is being started in a patient already receiving a strong CYP3A4 inhibitor (for schizophrenia or bipolar mania), the recommended starting dose is 1.5 mg orally every 3 days, with a possible increase to 1.5 mg orally every other day if warranted by clinical response and tolerability. For a patient on a strong CYP3A4 inhibitor who is being treated for bipolar depression or receiving adjunctive therapy for MDD, the dose is 1.5 mg orally every 3 days. If a strong CYP3A4 inhibitor is being added while the patient is already on a stable cariprazine dose, the cariprazine dose should be modified as follows: for those currently taking 1.5 or 3 mg once daily, reduce to 1.5 mg orally every 3 days upon starting the inhibitor; for those currently taking 4.5 or 6 mg once daily, reduce to 1.5 mg orally every other day upon starting the inhibitor. After the strong CYP3A4 inhibitor is stopped, an increase in the cariprazine dose may be required, guided by clinical response and tolerability1.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism of cariprazine
How to manage this interaction
This combination can be used safely with dose planning. Because itraconazole raises cariprazine levels, your care team will typically lower or space out your cariprazine dose and monitor how you feel and tolerate it.
- Keep taking both exactly as prescribed unless told otherwise.
- Expect a reduced or less frequent cariprazine dose (for example, dosing every 3 days or every other day) while you are on itraconazole.
- When itraconazole is stopped, your cariprazine dose may need to be raised again.
- Tell your pharmacist or prescriber about new drowsiness, restlessness, dizziness, or muscle stiffness.
Your exact dose will be individualized by your care team.
Management is individual — confirm any change with your pharmacist or prescriber.
Literature reports
1 report — tap to read
a) In drug interaction studies, giving cariprazine 0.5 mg/day together with ketoconazole 400 mg/day led to an increase in total cariprazine AUC and Cmax by roughly 100% 1.
Common questions
Can I take Itraconazole and Cariprazine together?
Itraconazole blocks the enzyme that clears cariprazine, so cariprazine levels can roughly double; your care team will lower or space out your cariprazine dose and monitor you while you take both. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Itraconazole and Cariprazine 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 Itraconazole and Cariprazine interaction managed?
This combination can be used safely with dose planning. Because itraconazole raises cariprazine levels, your care team will typically lower or space out your cariprazine dose and monitor how you feel and tolerate it. Keep taking both exactly as prescribed unless told otherwise. Expect a reduced or less frequent cariprazine dose (for example, dosing every 3 days or every other day) while you are on… 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.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Itraconazole or Cariprazine 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: VRAYLAR(R) oral capsules, cariprazine oral capsules. AbbVie Inc. (per FDA), North Chicago, IL, 2024. DailyMed
Keep reading about Itraconazole
Keep reading about Cariprazine
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