Smoking surpasses injection as the main method of drug use in overdose deaths in the US, warns study


Smoking has surpassed injection as the most common way to consume drugs in overdose deaths in the United States, according to a new government study.

The Centers for Disease Control and Prevention (CDC) said that this study —published on Thursday— is the most comprehensive analysis of how Americans consumed the drugs that caused their death.

CDC officials decided to study the issue after seeing reports from California suggesting that smoking fentanyl was becoming more common than injecting it. Potent and illicit versions of the analgesic have been involved in more overdose deaths than any other drug.

Some previous studies have pointed out that smoking fentanyl is relatively less lethal than injecting it, and that any reduction in overdose deaths with injected drugs is positive, said Lauren Tanz, the lead author of the study.

But "smoking and injecting carry a substantial risk of overdose," and it is not known whether the preference for smoking to consume fentanyl reduces overdose deaths in the United States, Tanz said, a CDC scientist specializing in overdose study.

Illicit fentanyl is a drug notoriously known for its potency that, in powder form, has been increasingly incorporated into heroin or other drugs. In recent years, it has been one of the main drivers of the overdose epidemic in the United States. Overdose deaths in the country increased slightly in 2022 after two major increases during the Covid-19 pandemic, and provisional data from the first nine months of 2023 indicate that they recorded a slight increase last year.

For years, fentanyl has been consumed mainly by injection, but increasingly drug users smoke it. People put the powder on aluminum foil or in a glass pipe that they heat from below, and inhale the vapor, explained Alex Karl, a researcher at RTI International, who studies drug users in San Francisco.

Smoked fentanyl is not as concentrated as that of a syringe, but for some users, smoking it has its advantages, Kral said. People who inject often present pus-filled abscesses on the skin and risk contracting hepatitis and other diseases, and smoking it allows to avoid these risks.

"One person showed me his arms and said: 'Hey, look at my arm! It looks beautiful! Now I can wear t-shirts and get a job because I don't have those marks'", Kral said.

CDC researchers studied the trend using a national database compiled from death certificates, toxicology reports, and reports from medical examiners and medical experts.

They were able to obtain adequate data from the District of Columbia and 27 states for the years 2020 to 2022. From those sites, they obtained information on how drugs were consumed in about 71 thousand of the total of more than 311 thousand overdose deaths in the United States in those three years, that is, about 23%.

Researchers found that between 2020 and 2022, the percentage of overdose deaths with evidence of smoked drug use increased 74%, while the percentage of deaths with evidence of injection use decreased 29%. The number and percentage of deaths with evidence of inhalation also increased, although not as notably as deaths related to smoked drugs, according to the study.

It is complicated to determine the exact percentages of deaths that occurred after smoking, injecting, inhaling, or ingesting drugs, experts say. In some cases, a person may have consumed different drugs by different routes. In other cases, a method of consumption was not identified.

The study found that, by the end of 2022, of the deaths whose method was identified, 23% of them occurred after smoking, 16% after injecting, 16% after inhaling, and 14.5% after ingesting.

Tanz noted that, in her opinion, the data are representative at the national level. The information comes from states in all regions of the country, and in all of them, it is possible to see increases in the consumption of smoked drugs and reductions in the consumption of injected drugs. Smoking was the most common route in the west and in the north-central region, while in the northeast and south it was tied with injection consumption, according to the study.

Kral described the study as "good for the most part," but said it has its limitations.

It can be difficult to determine the how and why of an overdose death, especially if there were no witnesses. Injections could be reported more frequently due to the marks of the syringes on the body; to detect the consumption of smoked drugs, "probably (the researchers) would need to find a pipe or aluminum foil at the place and decide whether to record it in writing or not," he said.

Kral also noted that many people who smoke fentanyl use a straw to inhale the vapors of the powder as it burns, and it is possible that the researchers saw one of them and assumed that the drug had been inhaled.