High prescription drug prices may be forcing people to skip the medicines they need to treat and manage their health conditions.

As prescription drug prices continue to rise, more people are being forced to choose between paying for their medications and buying basic necessities.

About one-quarter of people in the United States said they have difficulty affording their medications, according to a 2016 report by the Kaiser Family Foundation.

The report also showed that overall prescription drug prices increased 8 percent in 2015, mainly due to new drugs, higher costs for existing drugs, and fewer drug patents expiring.

The list prices for the most commonly used brand-name drugs increased almost 208 percent between 2008 and 2016.

However, during the same time, generic drug prices fell about 74 percent.

Some people pay more for their prescription drugs, while others pay less, depending on what their health insurance plan covers. In 2015 the average out-of-pocket spending was $142 per person.

Among traditional therapies, diabetes medications were the most expensive, in terms of out-of-pocket costs. This was followed by drugs for pain and inflammatory conditions, high blood cholesterol, and ADHD.

For specialty drugs, out-of-pocket costs were highest for drugs used to treat inflammatory conditions, cancer, multiple sclerosis, and HIV.

High prescription drug prices offer a harsh economic lesson — as the out-of-pocket cost goes up, the number of people using the drug often goes down.

In a recent study in JAMA Cardiology, researchers saw this happen with people who were approved by their insurer to fill a prescription for alirocumab or evolocumab, two new specialty drugs for treating elevated “bad” cholesterol levels.

Co-pays for these drugs ranged from $0 to $2,822 per month.

Almost 93 percent of people with no co-pay filled their prescription. This dropped to 20 to 25 percent for people with a co-pay over $350 per month.

A group of researchers from the Cleveland Clinic found a similar trend with two common heart medications — nitroprusside and isoproterenol.

In a letter to the editor of the New England Journal of Medicine, the researchers reported that between 2012 and 2015 the cost of nitroprusside increased from about $27 to $881. The cost of isoproterenol increased from about $26 to $1,790.

During this time, patient use of these drugs decreased by 53 percent and 35 percent, respectively.

For people struggling to make ends meet, the cost of prescription drugs may have already reached a tipping point.

According to a recent Truven Health Analytics-NPR Health Poll, people with annual incomes under $25,000 were more likely to not fill a prescription, compared to people with higher incomes. Almost all of the lower-income people cited high cost as the reason.

But this group isn’t alone.

“High drug prices appear to affect everyone across the socioeconomic spectrum. So it’s not just low-income people who are having these issues,” Minal Patel, PhD, MPH, an assistant professor in the University of Michigan School of Public Health, told Healthline.

Patel added that this is especially true “in the context of severe, acute illnesses like cancer, or major chronic diseases.”

These conditions are often treated with newer — and more expensive — specialty medications, which may not be fully covered by insurance.

When faced with high out-of-pocket costs, people may opt to skip their medications.

This can worsen their health and quality of life. It may also lead to higher medical costs down the road.

“There have been some studies showing that people who cut back on medicines are at increased risk for hospitalizations and emergency department visits, which we know are very expensive forms of care,” said Patel.

Some research estimates that when people don’t take their medications as prescribed for a chronic health condition, it costs the U.S. health care system between $100 billion and $289 billion annually.

This includes people not filling their prescriptions due to high cost, skipping doses, or cutting their pills in half to make them last longer. It also includes people forgetting to take their medications or not taking them because of side effects.

Other studies on Medicare enrollees found that older adults sometimes cut back on basic needs such as food in order to pay for their medications.

Although high drug costs can deter people from taking their medications, lower costs can have the opposite effect.

A 2016 study in the Journal of Clinical Oncology found that older women who received Medicare Part D subsidies were more likely to continue hormonal therapy after breast cancer surgery.

People facing high drug costs have many options for lowering their out-of-pocket payments, including rebates from drug companies and prescription assistance programs.

The problem is finding out what works for your situation.

“People don’t always know about everything that’s available to them,” said Patel. “I think we need better structures to help people understand what they qualify for and what’s available to them.”