More harms for people who both inject and smoke methamphetamine, new study shows

September 2021
McKetin, R., Sutherland, R., Peacock, A., Farrell, M. and Degenhardt, L. (2021), Patterns of smoking and injecting methamphetamine and their association with health and social outcomes. Drug Alcohol Rev..

Researchers from the National Drug and Alcohol Research Centre (NDARC), UNSW Sydney, found that people who both inject and smoke methamphetamine, injected drugs more often, used methamphetamine more often and had more violent behaviour and more involvement in crime.

“Traditionally we think of people either injecting the drug, or smoking the drug”, said lead researcher, Associate Professor Rebecca McKetin.

“Smoking tends to often be seen as the lesser evil.”

The study found a cohort of people who usually injected methamphetamine had also taken up smoking the drug, with this being associated with more frequent injecting drug use and more methamphetamine use, greater involvement in crime, and more violent behaviour.

“This study suggests that people who inject methamphetamine adopt smoking as a complement to their injecting drug use, rather than as a replacement, resulting in increased frequency of methamphetamine use and more related harms,” said Associate Professor McKetin.

“There was no evidence that people stopped injecting methamphetamine when they took up smoking the drug.”

The study analysed data from 444 participants in the Methamphetamine Treatment Evaluation Study (MATES), and found at baseline, 56 per cent of participants had only injected methamphetamine in the past month, 18 per cent had only smoked it, and 26 per cent had both injected and smoked (concurrent injecting and smoking).

The study identifies a need to address both injection-related harms (e.g., HIV prevention) and non-injection related harms (crime, with poor mental health) among people who use methamphetamine.

“Many of these harms could be reduced by providing effective treatment,” said Associate Professor McKetin.

“Good access to harm reduction services for people who use stimulants would also reduce blood-borne and sexually transmitted infections, including providing pre-exposure prophylaxis (PreP) to high-risk populations for HIV transmission.”

The study says efforts are needed to address heavier methamphetamine use and harms among people who concurrently smoke and inject methamphetamine.

Read the full study here