1-(2-Methoxyphenyl)-3-azabicyclo[3.1.0]hexane Hydrochloride-d5 is labelled 1-(2-Methoxyphenyl)-3-azabicyclo[3.1.0]hexane Hydrochloride (M320815), an isomer of 1-(3-Methoxyphenyl)-3-azabicyclo[3.1.0]hexane Hydrochloride (M320820) which is a nonnarcotic analgesic agent.