Purpose Drug checking is a popular method to reduce risks of drug use. In many countries, including Finland, legislation restricts implementing drug checking. The aim of this study was to explore whether some benefits of drug checking could be achieved by substance residue analysis.

Design/methodology/approach Drug paraphernalia (mostly empty plastic bags) were used in the study. Participants left a sample and information about the former content to a local needle exchange point. After laboratory analysis, participants could return for the results and a short consultation on the substance(s) found. Afterward, participants were asked whether they would still use the batch.

Findings Ninety-eight samples were received. In most cases, the samples had originally been sold as amphetamine (n = 39). Overall, laboratory results matched with supposed content in 52 cases, but in 21 cases, the sold content had been altered, in 17 cases, only other psychoactive substances were found and in 8 cases, no traces of psychoactive substances were found. Participants returned for results in two-thirds of the cases. When the laboratory result did not match participants’ expectations, the majority of participants estimated they would not use the same batch (17/25) or would use it in a different way (2/25).

Originality/value While reports on drug checking are numerous, studies exploring possibilities to achieve harm-reducing benefits of drug checking by analyzing drug residues are scarce. The results of this pilot study suggest some benefits of drug checking can be achieved by substance residue analysis.