Which of the following is a potential adverse effect of Valbenazine?

• A. QT prolongation
• B. Hyperglycemia
• C. Severe hypertension
• D. Increased appetite

Answer: (A)

Valbenazine can prolong the QT interval, which is a potential adverse effect to watch for. This means it can affect the heart’s electrical repolarization, visible on an electrocardiogram as a longer QTc. Because a longer QT can raise the risk of dangerous arrhythmias like torsades de pointes, clinicians monitor the ECG, check electrolytes (potassium, magnesium), and review other medications that also extend the QT interval. Avoid combining valbenazine with other QT-prolonging drugs if possible, and be cautious in patients with a known long QT syndrome or significant electrolyte abnormalities.

Hyperglycemia, severe hypertension, and increased appetite are not typical adverse effects associated with valbenazine, so they don’t fit as common risks for this medication.