Drug Interaction Report

Insulin Aspart, Recombinant 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

Cariprazine

Vraylar Vraylar®
+

Insulin Aspart, Recombinant

Fiasp Kirsty Merilog NovoLog
Dr. Brian Staiger, PharmD, BCPS
Medically reviewed by
Updated Jul 16, 2026
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Interaction severity
Major
Potentially serious — often needs a change or close monitoring.
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.

Of 134 documented Insulin Aspart, Recombinant interactions, 95 are rated major — including this one.
Worried about symptoms right now? Contact your pharmacist or prescriber, or call Poison Control at 1-800-222-1222 (US). Call 911 for an emergency.
At a glance + Theoretical Effects may be weaker
The Bottom Line
Cariprazine may make your mealtime insulin work less well, so your blood sugars could run higher. Keep both as prescribed, monitor your glucose more closely, and let your care team adjust your insulin dose if needed.

Here's what's going on: Cariprazine (Vraylar) is an atypical antipsychotic. Medicines in this family can raise blood sugar and make your body less sensitive to insulin. That means your mealtime insulin (aspart, like NovoLog or Fiasp) may not lower your blood sugar as well as it usually does.

The good news is this is very manageable. Your care team can check your blood sugar more often and, if needed, adjust your insulin dose to fit your body. Please don't change either medicine on your own. Just let your doctor or pharmacist know you take both, and keep an eye on your readings so your team can keep things on track.

Effect: Atypical antipsychotics, including cariprazine, may attenuate the glucose-lowering effect of insulin aspart (a pharmacodynamic interaction).

  • Direction: Reduced insulin efficacy, potential hyperglycemia. Neither agent is metabolically activated in a way that reverses this.
  • Mechanism: Unknown; consistent with class-related impairment of glucose homeostasis / insulin sensitivity and possible weight gain.
  • Evidence: Theoretical; severity rated major.
  • Onset: Unspecified.
  • Management: Increase frequency of glucose monitoring; insulin dose may need to be individualized and adjusted. Monitor HbA1c and metabolic parameters over time.
Onset
unspecified
Evidence
theoretical
Severity
Major

What happens

Reduced blood glucose lowering effect of insulin

Interaction Deep Dive

The glucose-lowering activity of insulin aspart may be diminished when it is taken together with atypical antipsychotics. When insulin aspart and atypical antipsychotics are used concurrently, patients may need their dosages adjusted and their glucose levels monitored more often12.

Why it happens (mechanism)

Unknown

How to manage this interaction

Keep taking both medicines as prescribed unless your prescriber tells you otherwise. This interaction is manageable with monitoring.

  • Your care team may ask you to check your blood sugar more often, especially when cariprazine is started or its dose changes.
  • Your insulin dose may need to be adjusted and individualized by your team to keep your sugars in range.
  • Share your glucose logs and tell your pharmacist or doctor about any higher-than-usual readings, increased thirst, or frequent urination.

Bring up any concerns at your next visit so your team can tailor your plan.

Management is individual — confirm any change with your pharmacist or prescriber.

Common questions

Can I take Insulin Aspart, Recombinant and Cariprazine together?

Cariprazine may make your mealtime insulin work less well, so your blood sugars could run higher. Keep both as prescribed, monitor your glucose more closely, and let your care team adjust your insulin dose if needed. Always confirm with your pharmacist or prescriber before making any change.

How serious is the Insulin Aspart, Recombinant 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 Insulin Aspart, Recombinant and Cariprazine interaction managed?

Keep taking both medicines as prescribed unless your prescriber tells you otherwise. This interaction is manageable with monitoring. Your care team may ask you to check your blood sugar more often, especially when cariprazine is started or its dose changes. Your insulin dose may need to be adjusted and individualized by your team to keep your sugars in range. Share your glucose logs and tell your… 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 Insulin Aspart, Recombinant 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 (2)

  1. Product Information: KIRSTY(TM) subcutaneous injection, intravenous injection, insulin aspart-xjhz, recombinant subcutaneous injection, intravenous injection. Biocon Biologics Inc. (per FDA), Cambridge, MA, 2025. DailyMed
  2. Product Information: MERILOG subcutaneous injection, insulin aspart-szjj, recombinant subcutaneous injection. sanofi-aventis U.S. LLC (per FDA), Bridgewater, NJ, 2025. DailyMed
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This information is for education, not a substitute for professional medical advice. Do not start, stop, or change any medication without talking to your pharmacist or prescriber.