Tetrabenazine and Olanzapine Interaction
Drug interaction information between Tetrabenazine and Olanzapine.
Tetrabenazine and Olanzapine have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Tetrabenazine and Olanzapine. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Both drugs lower dopamine activity in the brain, which can cause stiff muscles, tremors, or a dangerous fever.
FDA Label Information
7.6 Neuroleptic Drugs The risk for Parkinsonism, NMS, and akathisia may be increased by concomitant use of tetrabenazine and dopamine antagonists or antipsychotics (e.g., chlorpromazine, haloperidol, olanzapine, risperidone, thioridazine, ziprasidone) [see Warnings and Precautions ( 5.4 , 5.5 , 5.6 )] .
Tetrabenazine Also Interacts With
- Deutetrabenazine major
- Valbenazine major
- Risperidone moderate
- Ziprasidone moderate
- Haloperidol moderate
Olanzapine Also Interacts With
- Fluoxetine major
- Omeprazole minor
- Warfarin minor
- Diazepam minor
- Carbamazepine minor
Frequently Asked Questions
What SPL severity band is on file for Tetrabenazine + Olanzapine?
Compiled FDA labeling labels this pair moderate. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Olanzapine has 26 labeled pairs on file vs Tetrabenazine's 16. In the moderate band specifically: Tetrabenazine has 9 (also Risperidone, Ziprasidone, Haloperidol, Chlorpromazine); Olanzapine has 1.
What mechanism field is on file for Tetrabenazine and Olanzapine?
Both drugs lower dopamine activity in the brain, which can cause stiff muscles, tremors, or a dangerous fever.
Tetrabenazine carries more major-labeled pairs than Olanzapine
SPL source-record counts only. This page's band is moderate · classes on file: Tetrabenazine (VMAT2 Inhibitor); Olanzapine (Atypical Antipsychotic).
Tetrabenazine has 2 major-labeled pairs vs Olanzapine's 1. This page itself is in the moderate band, not the major band.
2 major · 9 moderate · 5 minor · 16 total
- Other moderate peers for Tetrabenazine
- Risperidone
- Ziprasidone
- Haloperidol
- Chlorpromazine
1 major · 1 moderate · 24 minor · 26 total
Olanzapine has no other moderate-band peer in this dataset besides Tetrabenazine.
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.