Psychiatry and Mental Healthcommon
A 46-year-old woman with bipolar disorder has been stable on lithium carbonate for five years. She presents with two days of nausea, vomiting and unsteadiness on her feet, and her hands now shake so coarsely that she spills her tea. Over the past fortnight her general practitioner commenced several new medications for unrelated problems. Her serum lithium concentration is 2.1 mmol/L (therapeutic 0.6-0.8). Which one of the following newly commenced medications is the most likely cause of her presentation?