Haloperidol and Tetrabenazine Interaction
Drug interaction information between Haloperidol and Tetrabenazine.
Haloperidol and Tetrabenazine have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Haloperidol and Tetrabenazine. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.
How They Interact
Combining these drugs increases the risk of heart rhythm changes and severe movement disorders like Parkinsonism.
What To Do
This combination should be avoided because it can lead to heart problems and serious muscle reactions.
FDA Label Information
7.5 Drugs That Cause QTc Prolongation Tetrabenazine causes a small prolongation of QTc (about 8 msec), concomitant use with other drugs that are known to cause QTc prolongation should be avoided, these including antipsychotic medications (e.g., chlorpromazine, haloperidol, thioridazine, ziprasidone), antibiotics (e.g., moxifloxacin), Class 1A (e.g., quinidine, procainamide) and Class III (e.g., amiodarone, sotalol) antiarrhythmic medications or any other medications known to prolong the QTc interval. 7.6 Neuroleptic Drugs The risk for Parkinsonism, NMS, and akathisia may be increased by...
Haloperidol Also Interacts With
- Fluoxetine moderate
- Bromocriptine minor
- Bupropion minor
- Carbamazepine minor
- Clomipramine minor
Tetrabenazine Also Interacts With
- Deutetrabenazine major
- Valbenazine major
- Olanzapine moderate
- Risperidone moderate
- Ziprasidone moderate
Frequently Asked Questions
Can I take Haloperidol and Tetrabenazine together?
This is a moderate interaction. This combination should be avoided because it can lead to heart problems and serious muscle reactions.
How serious is the interaction between Haloperidol and Tetrabenazine?
This interaction is classified as "moderate" severity by the FDA. Moderate interactions may worsen your condition or change how your medications work.
Why do Haloperidol and Tetrabenazine interact?
Combining these drugs increases the risk of heart rhythm changes and severe movement disorders like Parkinsonism.
Understanding the Haloperidol and Tetrabenazine Interaction
FDA-approved prescribing information for these two drugs flags their combination as a moderate-severity interaction. Haloperidol belongs to the Typical Antipsychotic class and Tetrabenazine belongs to the VMAT2 Inhibitor class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Combining these drugs increases the risk of heart rhythm changes and severe movement disorders like Parkinsonism. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.
Context around a specific patient determines real-world impact. Haloperidol has 14 total documented interactions on file in this dataset, and Tetrabenazine has 16. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: This combination should be avoided because it can lead to heart problems and serious muscle reactions. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.
An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Haloperidol or Tetrabenazine based on a web page, speak with your prescriber or pharmacist before making any change.
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.
Read our methodology - how this data is sourced, computed, and verified.