AKT-5367

A 47-year-old woman presents with severe vertigo provoked by moving her head, including rolling over in bed, lying down, sitting up, leaning forward or even just turning the head in a horizontal plane. The attacks of vertigo last 20–30 seconds and resolve quickly if the head is kept still. Nausea is associated with the episodes. The Dix–Hallpike manoeuvre reproduces symptoms of vertigo and nystagmus.
Which of the following is the most appropriate intervention?