The case of Heather Holland, a Texas teacher who died of the flu this month, has become a cause of outrage over high drug prices. The 38-year-old held off on buying medication prescribed by her doctor because of sticker shock: she would have had to pay a $116 copay under her insurance.

Holland’s husband purchased the prescription for her one day later. She had decided not to buy it out of frugality, not because the family couldn’t afford it, her husband told the Wall Street Journal.

It’s unclear whether delaying taking the medicine had any effect on her death, but the case highlights a growing problem for Texas teachers and many other Americans: Insurance costs have been climbing rapidly.

Insurance premiums under a commonly used plan by Texas teachers roughly doubled to above $600 in fiscal 2017 from fiscal 2006, according to data from the Teacher Retirement System of Texas, its provider. Pharmacy costs, meanwhile, went up 66% in the same period.

But state contributions towards insurance costs have stayed flat, at $75, since 2003. That means teachers have to pay a higher share of a ballooning total.