A new study has found that almost all people who overdose on prescription opioids or painkillers still get their prescriptions renewed.

Dr. Marc R. Larochelle, who was the lead author on the study, called the findings “surprising and concerning” in an interview with Reuters.

A total of 3,000 patients were identified during the course of the study who had a nonfatal overdose between 200 and 2012 while on a prescription for opioids used to treat chronic pain, according to the Reuters report. This can include a range of drugs, including oxycodone, codein, and hydrocodone to name a few. A total of 212 individuals in that group had overdoses, making up 7 percent of the total.

The study found that nine out of every 10 patients still got prescriptions for painkillers even after having an overdose — and half had gotten it from the very same doctor.

The problem is likely a lack of information, researchers believe. The doctors who prescribe the pills probably don’t have a clue that their patient has overdosed on the opioids — there just isn’t a system in place to make them aware. It’s difficult for a doctor to know that even when it’s the same patient he or she has been seeing for years, let alone when the patient attempts to switch doctors in order to get a new prescription. The fact of the matter is that many doctors are dependent on patients letting them know they overdosed, and most patients aren’t likely to do that. In addition, most physicians don’t get training in this area, or have many resources at their disposal.

In addition, even if the doctor does know, he or she must weigh the benefits of continuing to have an opioid prescription — sudden withdrawal from opioids can actually be fatal in many cases — versus the risk of prescribing a pill that the patient has already OD’ed on.