Might produce CNS effects. Use in sulfonylurea allergy contraindicated. Use with caution in prediabetes or diabetes mellitus (possible change in glucose control), in pulmonary obstruction, emphysema, or advanced pulmonary disease (might precipitate or aggravate acidosis), and in the elderly. Avoid use in marked hepatic impairment, including cirrhosis (risk of developing hepatic encephalopathy), and in marked renal impairment.