(2003; 31 pages) [French] [Spanish]
Oripavine, O3-demethylthebaine, is a phenanthrene alkaloid contained in species of the Papaver plant. It is a major metabolite of thebaine.
Oripavine has not previously been reviewed by WHO in the context of international control. However, in a WHO review of the dependence potential of thebaine held in 1980 (12), oripavine was suggested to be a metabolite of thebaine in animals possibly involved in the dependence potential.
In recent years, large quantities of concentrate of poppy straw (defined as “all parts (except the seeds) of the opium poppy after mowing”) containing oripavine as the main alkaloid has been produced, traded and used for the production of opium alkaloids. It is an easy industrial process to convert oripavine into thebaine through methylation. Thebaine is in Schedule I of the 1961 Convention because it is a precursor of codeine and morphine. For this reason, the convertibility of oripavine may meet the scheduling criteria for placing it in the same Schedule as thebaine. However, the Commentary on the 1961 Convention indicates that the purpose of controlling drugs which are convertible to scheduled narcotic drugs, is to prevent the abuse of the narcotic drugs manufactured by the conversion process. Although animal tests have shown that thebaine has some abuse potential, no actual abuse of thebaine has been reported. It is therefore questionable whether the convertibility criterion could be applied for the scheduling of a substance when the drug produced by its conversion is used only as a starting material for the manufacture of other narcotic drugs. An additional problem is that there is no authoritative guidance on how to distinguish between the criteria of the 1961 Convention concerning convertibility and the criteria introduced by the 1988 Convention (13) concerning the control of precursors. Since the Guidelines do not provide any guidance on this question, the Committee was unable to recommend critical review of oripavine at this stage.
The Committee urged WHO to develop additional scheduling guidelines in consultation with appropriate bodies of the United Nations for clarifying issues related to the conversion of precursors into scheduled substances.