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In California, People Have Transitioned from Injecting Heroin to Smoking Fentanyl, Study Suggests

A study of people in San Francisco reveals a precipitous drop in number of injections, which could reduce infectious disease risk

RESEARCH TRIANGLE PARK, N.C. — A new study by researchers at RTI International, the University of California San Diego and the University of Southern California suggests that people in California who use drugs are injecting heroin less frequently, preferring to smoke fentanyl instead.

The two-year observational study of 395 people in San Francisco assessed changes in injection frequency, opioid injection frequency and fentanyl smoking frequency in four six-month periods. The research team also conducted qualitative interviews asking about motivations for injecting and smoking opioids.

The median number of monthly injections was 17 in a six-month span from January to June 2020, a steep decline from the median of 92 monthly injections reported from July to December 2018.

“The public health community has long advocated, unsuccessfully, for people to avoid injecting drugs, because of the health complications associated with it,” said Alex Kral, Ph.D., Distinguished Fellow at RTI. “The trend of fewer injections, at least in California, could translate to a reduction in infectious disease risk.”

An increase in fentanyl smoking was revealed in qualitative interviews with participants, who reported the transition was related to difficulties accessing veins. After switching to smoking fentanyl, they reported benefits including how the drug felt, improved health, fewer financial constraints and reduced stigma.

Kral and his colleagues note the need for more research on the risks associated with smoking fentanyl. In the meantime, they make the case for the public health community to make accommodations for the trend.

“Our findings point to the need for harm reduction programs to provide clean and safe smoking supplies,” said Kral. “Safe consumption sites should consider ventilated smoking areas.”

Interviews with drug researchers and harm reduction service providers across the U.S. conducted as part the study indicated the switch to smoking fentanyl is mainly occurring in California, though more research is needed to understand why.

View the full study

Learn more about RTI’s opioid research