The United States is in the midst of the worst epidemic of drug overdoses in its history, with heroin and prescription drug mortality rates nearly five times higher than they were in the 1970s. However, addiction advocates believe it’s far harder to get drugs to treat an addiction than it is to get the drugs that cause it, a problem that’s helping to perpetuate thousands of unintentional deaths every year, The Washington Post reports.

According to the U.S. Centers for Disease Control and Prevention, 28,000 Americans died from opioid addiction in 2014. However, fewer than half of the 2.2 million people who need treatment for heroin or prescription drug use in this country are receiving it.

The problem is multifaceted. There is a major shortage of doctors nationwide willing to prescribe medication-assisted treatment (MAT) like buprenorphine, Vivitrol or methadone, which help reduce cravings and ease symptoms of withdrawal. Those who are willing to prescribe those drugs must take an eight-hour course and apply for a special license to do so. There is also a federal limit on the number of people each doctor who is willing to prescribe MAT can treat.

Meanwhile, nearly every U.S. physician (as well as nurse practitioners and physician’s assistants in many states) can write prescriptions for opioid painkillers like OxyContin, Vicodin and Percocet by signing on to a federal registry. In practice, this means that more than 900,000 practitioners in this country are able to prescribe prescription opioids, but only 32,000 have received a license to prescribe drugs designed to treat people who are addicted to them.