A method of detecting the presence of an NBOMe in a sample which comprises of contacting the sample with an activated p-quinone such as 2,3,5,6-tetrachloro-1,4-benzoquinone (TCBQ) and an aldehyde, for example acetaldehyde, and optionally a buffer and observing a colour change, which when present, correlates with the presence of an NBOMe. The ingredients may be provided in the form of a kit which can include a colour standard or comparison chart.