A spike in opioid overdoses in Minnesota has been called a medical epidemic, but a new surge in deaths related to counterfeit fentanyl has officials using another description.

Homicide.

Opioid-related deaths in Minnesota are increasingly being linked to street drugs that dealers secretly lace or substitute with fentanyl, a synthetic opioid more potent than heroin or common painkillers. Of the 401 opioid-related overdose deaths recorded in Minnesota last year, 43 percent were linked to fentanyl or other synthetics, according to preliminary figures released Monday by the Minnesota Department of Health. Five years ago, the number was 11 percent.

“The opioid epidemic … has also become a fentanyl public health crisis,” said state Health Commissioner Jan Malcolm. “These data confirm that Minnesotans addicted to opioids may unknowingly be exposing themselves to far greater and more deadly risks than they know.”

To address the challenge, state officials said they need to treat these deaths like homicides and trace lethal, counterfeit drugs to their sources.

“We’re working them backward to determine who is dealing these illicit substances,” said Drew Evans, superintendent of the Minnesota Bureau of Criminal Apprehension.

Overdose deaths related to fentanyl and other synthetic opioids rose 74 percent from 2016 to 2017, according to the Health Department report released Monday. That was enough to increase the overall number of drug overdose deaths in the state from 675 in 2016 to 694 in 2017 — even though deaths from common prescription opioid painkillers have remained constant in recent years.

An investigation into the 2016 death of pop star Prince concluded last month that he overdosed on counterfeit pills that were made to look like common painkillers but actually contained fentanyl.

Monday’s preliminary report didn’t determine how many deaths were caused by legally prescribed forms of fentanyl, such as patches and tablets, and how many stemmed from illicit versions. A final report on the deaths is expected in September.

Evans said the trend in overdose deaths matches the rising number of drug samples examined in the state crime lab that contain fentanyl. Drug dealers often substitute fentanyl in their product because it is strong, but cheaper than heroin and other substances. Fentanyl has even been found, paradoxically, in methamphetamine.

While law enforcement agencies in Minnesota have long had the authority to pursue third-degree homicide charges against people who distribute drugs that cause fatal overdoses, Evans said it is receiving a “renewed focus.”

‘Deterrent effect’

On Friday, authorities in Nicollet County charged a 38-year-old Mankato man with homicide and accused him of selling a drug containing fentanyl to a North Mankato woman who died in April from an overdose.

“The goal is to have that deterrent effect,” Evans said, “and to make sure drug dealers know that not only do you need to be looking over your shoulder when you’re dealing, but if you cause someone’s death, we’re going to work hard to hold you responsible.”

Apart from fentanyl, the number of overdose deaths involving other opioids in Minnesota is leveling off or even falling, according to Monday’s report.

The share of opioid overdose deaths related to prescription painkillers such as oxycodone and hydrocodone is declining. New prescribing guidelines and monitoring programs to identify doctors who prescribe excessively, as well as patients who seek opioids from multiple clinics, have reduced painkiller usage.

Minnesota now has the fourth-lowest rate of opioid painkiller prescriptions written in the U.S., said Dr. Rahul Koranne, chief medical officer of the Minnesota Hospital Association. Despite the progress, Koranne said doctors need to remain conservative in pain management, because opioid painkillers remain gateways to addiction and heroin and fentanyl use.

“Even one prescription of opioids in the right person,” he said, “can lead to addiction and, potentially, to death.”

Deaths involving heroin declined 29 percent from 2016 to 2017, the Health Department data show. That was the first substantial decline in more than a decade, though it may partly reflect renewed interest in other street drugs such as meth and cocaine. Deaths involving those drugs increased in 2017.

Crime labs and medical examiners also might be getting better at distinguishing deaths caused by heroin from those caused by fentanyl. That could be influencing both trends a bit, said Nate Wright, a Health Department epidemiologist, but there is little question that fentanyl deaths are actually on the rise.