Even physicians have trouble explaining why diabetes drug prices are so high.

Dr. Jeremy Greene, a professor of medicine and history of medicine at Johns Hopkins University,  recently told National Public Radio he had several patients at his clinic with out-of-control diabetes. When he discovered that many of those patients had so much trouble with diabetes due to the high cost of insulin, he inquired with several pharmacies about low-cost options. That’s when he learned that there were no generic alternatives for insulin.

Dr. Greene is not alone in his concern over exorbitant diabetes drug prices. In the United States, drug manufacturers set the prices for new products and, between 2002 and 2012, total expenditures on diabetes drugs, or antihyperglycemic medications, increased from $10 billion to $22 billion.

According to Current Diabetes Reports, the bulk of that increase was prompted by a dramatic rise in insulin expenditures, which grew sixfold.

Between 2002 and 2013, the cost of insulin per patient more than tripled — from an average of $231 per patient per year to $736 per patient per year, according to the research letter published in the Journal of the American Medical Association.

Why is there no generic insulin?

Dr. Greene decided to explore the history of insulin prices, publishing his findings in a 2015 paper titled “Why is There No Generic Insulin? Historical Origins of a Modern Problem.”

In the paper, Greene describes how this nearly 100-year-old remedy for diabetes underwent a dramatic manufacturing change in the 1970s. Drug makers switched from using insulin derived from pigs and cows to one created by injecting recombinant DNA into bacteria, which in turn produced large quantities of the hormone.

Soon afterward, the less expensive animal-derived insulin disappeared from the market.

The ensuing rise in insulin prices means some people spend as much out of pocket to manage their diabetes as they do on a mortgage.

In other instances, some families turned to the black market to purchase cheap insulin while others have set up crowdfunding pages or Facebook pages to ask for help.

What can be done?

There are some non-drug alternatives that may help with diabetes, such as talk therapy. Other drugs arriving on the market may also provide some measure of relief for diabetics.

Last month, the U.S. Food and Drug Administration approved Novo Nordisk’s Fiasp, aimed at helping diabetics control post-meal spikes in blood sugar. Novo Nordisk stated in a press release that Fiasp will have the same list price as its other diabetes drug, NovoLog, and it will be eligible for a savings card program as well as a patient assistance program to help offset costs.

In addition to new drugs coming on the market to help lower prices, politicians may try to provide relief. Legislators of both major parties are questioning why diabetes drug prices are so high, and both Hillary Clinton and Donald Trump spotlighted high prescription drug prices during the 2016 election. Several state legislatures also want to bring more transparency to the drug cost process.

Nevada passed a pricing transparency law for diabetes drugs in June and, thus far, it has withstood legal attacks from the pharmaceutical groups that would like to see it rescinded.

Other states attempting to enact their own versions of the Nevada law include Connecticut, Oklahoma, and California. Some states, such as Iowa, have not been able to keep their drug price transparency laws on the books after they were challenged in the courts.

For that reason, many will be watching to see what happens with Nevada.