A 56-year-old woman comes to the physician for a routine health maintenance examination. She has a 7-year history of type II diabetes mellitus. Current medications are metformin and glyburide. BMI is 35. Blood pressure is 160/90. Laboratory studies show:
HbA1c 9.4%
Serum urea nitrogen 35 mg/dL
Creatinine 2.6 mg/dL
AST 15 U/L (NR 5-40)
ALT 20 U/L (NR 7-56)
Which of the following is the next best step in management?
Add intermediate-acting insulin
Add pioglitazone
Discontinue metformin and increase dose of glyburide
Increase dose of metformin and glyburide
Switch from metformin and glyburide to intermediate-acting insulin
