Isoniazid and Valbenazine interaction
Isoniazid and Valbenazine: the Valbenazine prescribing label flags this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Valbenazine (INGREZZA) label · effective 2026-04-17
Dose adjustments due to drug interactions ( 2.4 , 7.1 ): Factors Dose Adjustments for INGREZZA and INGREZZA SPRINKLE Use of MAOIs with INGREZZA or INGREZZA SPRINKLE Avoid concomitant use with MAOIs.
Prevention or Management: Avoid concomitant use of INGREZZA or INGREZZA SPRINKLE with MAOIs, or within 14 days of discontinuing therapy with an MAOI.
In patients taking a strong CYP2D6 or CYP3A4 inhibitor, or who are CYP2D6 poor metabolizers, INGREZZA and INGREZZA SPRINKLE concentrations may be higher and QT prolongation clinically significant [see Clinical Pharmacology ( 12.2 )] .
For patients taking a strong CYP3A4 inhibitor, reduce the dose of INGREZZA or INGREZZA SPRINKLE to 40 mg once daily [see Dosage and Administration ( 2.4 , 2.5 )].
Use of strong CYP3A4 inhibitors with INGREZZA or INGREZZA SPRINKLE Recommended dosage is 40 mg once daily.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.