Valbenazine is associated with somnolence in what proportion of patients, according to the data?

• A. Diarrhea
• B. Somnolence
• C. Rash
• D. Hypertension

Answer: (B)

Valbenazine can produce CNS-related side effects because it inhibits VMAT2, reducing vesicular monoamine storage and release. This can lead to drowsiness or sleepiness, so somnolence is a recognized, relatively common adverse event in the data. In clinical trials, somnolence occurred with a measurable frequency, whereas the other listed adverse events—diarrhea, rash, and hypertension—were observed less frequently or not as consistently linked to valbenazine. Therefore, somnolence is the adverse effect most consistently seen in a meaningful portion of patients. If you need exact numbers, they’re provided in the drug labeling and trial reports, but the key idea is that somnolence is the prominent, data-supported CNS effect.