The cost of insulin increased from $4.34 per milliliter in 2002 to $12.92 in 2013, according to new research. The study looked at individual and prescription-level data for nearly 28,000 people from the Medical Expenditure Panel Survey. The data show that estimated spending for insulin per patient increased from about $231 to $736 during the study period. The researchers said that the estimated cost per patient in 2013 was about $508 for analog insulin and $228 for human insulin. Based on their findings, the authors concluded, "The estimated expenditure per patient for insulin in the United States in 2013 was greater than all other antihyperglycemic medications combined." They also noted that increased treatment intensity contributed to the rising costs. The significant increase in the mean price of insulin highlights the "need to reassess the effectiveness and cost-effectiveness of alternative antihyperglycemic therapies," the researchers added.