Nirmatrelvir and Aripiprazole Injection: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Jul 11, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Aripiprazole Injection
Nirmatrelvir
No brand names on recordHow 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 ARIPiprazole or ARIPiprazole lauroxil (prodrug of ARIPiprazole) exposure
Interaction Deep Dive
Concomitant use of nirmatrelvir/ritonavir and ARIPiprazole or ARIPiprazole lauroxil (prodrug of ARIPiprazole) may increase ARIPiprazole or ARIPiprazole lauroxil exposure. Adjust dosage of ARIPiprazole or ARIPiprazole lauroxil as needed2. Avoid use of ARIPiprazole when administered concomitantly with a strong CYP3A4 inhibitor, like ritonavir, for more than 14 days. Reduce the dosage of ARIPiprazole when used concomitantly with strong CYP3A4 inhibitors for more than 14 days 1.
Why it happens (mechanism)
Unknown
Common questions
Can I take Nirmatrelvir and Aripiprazole Injection together?
Increased ARIPiprazole or ARIPiprazole lauroxil (prodrug of ARIPiprazole) exposure Always confirm with your pharmacist or prescriber before making any change.
How serious is the Nirmatrelvir and Aripiprazole Injection 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 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 Nirmatrelvir or Aripiprazole Injection 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: ABILIFY ASIMTUFII(R) intramuscular extended-release suspension, aripiprazole intramuscular extended-release suspension. Otsuka America Pharmaceutical Inc (per FDA), Rockville, MD, 2023.
- Product Information: PAXLOVID(TM) oral tablets, nirmatrelvir oral tablets, ritonavir oral tablets. Pfizer Labs (per FDA), New York, NY, 2025. DailyMed
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