• Posted June 1, 2023

Most Injection Drug Users Are Not Seeking Out Fentanyl: Study

Many Americans who inject illicit drugs are unknowingly getting fentanyl mixed in with their heroin, which can increase their risk for overdose and perhaps their tolerance for the drug.

About 80% of injection drug users in New York City test positive for fentanyl, but only 18% intended to use that drug, according to research from NYU School of Global Public Health.

"As the proportion of drug overdose deaths involving fentanyl continues to increase, it's important to monitor how often people are exposed to fentanyl and any changes in preference for fentanyl among people who use drugs,"the study's lead author, Courtney McKnight, said in a school news release. She is a clinical assistant professor of epidemiology at NYU School of Global Public Health.

More than 100,000 Americans died of drug overdoses in 2021. About two-thirds of those deaths involved illicit fentanyl. The synthetic opioid is 50 to 100 times more potent than morphine, McKnight and her team pointed out.

For the study, the researchers surveyed and interviewed injection drug users in 2021 and 2022. More than 300 people answered the surveys and 162 agreed to interviews.

All survey participants underwent drug testing for fentanyl, heroin, other opioids, and stimulants so that the researchers could compare toxicology results with their self-reported drug use.

The study found that fentanyl was the most common recently used drug. About 83% of participants tested positive for it, including 46% who tested positive for both fentanyl and heroin, and 54% who tested positive for fentanyl without heroin.

"The overwhelming majority of people in this study -- regardless of intentionality of recent fentanyl use -- reported heroin as their main drug, indicating a strong preference for heroin over fentanyl. Yet, as our urine toxicology data indicate, people who inject drugs seem to have little agency in avoiding fentanyl,"said McKnight, who is also a researcher with NYU's Center for Drug Use and HIV/HCV Research.

Nearly one-quarter of the study participants reported having overdosed at least once in the previous six months. This included 36% of those who intentionally used fentanyl and 21% of those who reported no recent fentanyl use but tested positive for it. It also included 19% who reported no recent fentanyl use and tested negative for it.

Fentanyl has been the most common drug involved in overdose deaths in New York City since 2017.

People who intentionally used fentanyl were more likely to be younger, white, use drugs more often and test positive for stimulants, according to the study.

Concerns about overdosing were common among study participants. Most used strategies to prevent overdose, including keeping the opioid overdose reversal drug naloxone (Narcan) nearby, using smaller amounts of the drug, using drugs around others and having a trusted dealer.

"Nearly every person discussed the increased frequency of overdoses -- a constant reminder of the lethality of the drug supply. A few said that the regularity with which overdoses were occurring in New York City was like nothing they had ever experienced,"McKnight said.

Interviews also indicated that people who inject drugs may be developing an increased tolerance to fentanyl. This may drive a greater preference for the more potent drug, according to the study authors. Meanwhile, the potency of heroin has declined.

"New York City is home to the country's first two legally sanctioned overdose prevention centers, which opened in 2021 and have already saved hundreds of lives, but more support and access to these programs are needed to further reduce overdose mortality,"McKnight said.

The research was supported by the U.S. National Institute on Drug Abuse. The findings were published May 31 in the International Journal of Drug Policy.

More information

The U.S. Centers for Disease Control and Prevention has more on fentanyl.

SOURCE: NYU School of Global Public Health, news release, May 31, 2023