Propafenone and Valbenazine interaction
Propafenone and Valbenazine: both prescribing labels flag 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 Propafenone (propafenone hydrochloride) label · effective 2026-01-29
• Avoid use with other antiarrhythmic agents or drugs that prolong the QT interval.
It may also worsen premature ventricular contractions or supraventricular arrhythmias, and it may prolong the QT interval.
Use with Drugs that Prolong the QT Interval and Antiarrhythmic Agents The use of propafenone hydrochloride extended-release capsules in conjunction with other drugs that prolong the QT interval has not been extensively studied.
From the Valbenazine (INGREZZA) label · effective 2026-04-17
For patients who are CYP2D6 poor metabolizers or are taking a strong CYP2D6 inhibitor, dose reduction may be necessary.
Use of strong CYP2D6 inhibitors with INGREZZA or INGREZZA SPRINKLE Recommended dosage is 40 mg once daily.
Strong CYP2D6 Inhibitors Clinical Implication: Concomitant use of INGREZZA or INGREZZA SPRINKLE with strong CYP2D6 inhibitors increased the exposure (C max and AUC) to valbenazine’s active metabolite compared with the use of INGREZZA or INGREZZA SPRINKLE alone [see Clinical Pharmacology ( 12.3 , 12.5 )] .
Prevention or Management: Reduce INGREZZA or INGREZZA SPRINKLE dose when INGREZZA or INGREZZA SPRINKLE is coadministered with a strong CYP2D6 inhibitor [see Dosage and Administration ( 2.5 )].
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.