MRCP2-0822

A 49-year-old man has been referred to the endocrinology clinic due to polydipsia and polyuria. He has a medical history of hypertension and bipolar disorder, but cannot recall which medication he is taking for the latter. His GP conducted blood tests and found elevated blood glucose, with an HbA1c level of 62 mmol/mol (normal range: 42-48). What is the probable medication responsible for this result?