Abstract: Compositions and methods are provided for decreasing blood glucose levels in an animal or for preventing or delaying the onset of a rise in blood glucose levels in an animal, comprising administering to said animal an antisense inhibitor of PTP1B expression in combination with at least one glucose-lowering drug. The present invention is also directed to compositions and methods for improving insulin sensitivity in an animal or for preventing or delaying the onset of insulin resistance in an animal. Also provided are compositions and methods for treating or preventing a metabolic condition in an animal. The metabolic condition may be, e.g., diabetes or obesity.