Total Medicare part D spending on EpiPen auto-injectors rose from $7.0 million in 2007 to $87.9 million in 2014 – an increase of 1,151%, according to an analysis released Sept. 20 by the Kaiser Family Foundation.

The number of EpiPen users also increased over that time, however, bringing with it a commensurate 159% rise in the number of prescriptions. Those two trends took the average cost of a single EpiPen prescription from $71 in 2007 to $344 in 2014, the Kaiser analysis showed.

That increase in cost per prescription did not fail to at least double overall medical care price inflation for each year from 2008 to 2014. In 2008, when the two trends were closest together, the EpiPen cost per prescription rose 7.4% from the year before, compared with 3.7% for overall medical spending. In 2014, Medicare part D’s cost for an EpiPen prescription rose 34% from the year before, which was 14 times higher than the 2.4% increase in total medical spending, Kaiser noted.

The analysis was based on a 5% sample of Medicare prescription drug event claims and included beneficiaries who had a least 1 month of part D coverage and one EpiPen prescription during the year. Estimates are not adjusted for inflation and do not include any possible manufacturer discounts, Kaiser said.