Validity of noscapine and papaverine metabolites as markers of heroin misuse in the context of diamorphine treatment. A survey of urine samples from non-substance misusing patients prescribed diamorphine (2009)

ENGLISH :
Background: The use of prescribed injectable diamorphine (pharmaceutical heroin) as a treatment for heroin dependence remains controversial. The detection of urinary morphine and 6-monoacetylmorphine as indicators of street heroin misuse is confounded in patients prescribed diamorphine and there is no alternative biomarker in routine use. A previous paper reported on the gas chromatography-mass spectrometry analysis of over 1000 urine samples from patients of a substance misuse service, and concluded that the detection of papaverine and noscapine metabolites was likely to provide a reasonably sensitive and highly specific means of identifying the use of street heroin in patients prescribed diamorphine. Aims: In this study the potential for the parenteral administration of pharmaceutical diamorphine to give rise to the detection of these putative markers of street heroin in urine is examined. Design: Over a 15-month period, 57 patients from seven hospices in the UK provided pre- and post-diamorphine infusion samples. Samples were analysed by gas chromatography-mass spectrometry using the previously described procedure. Findings: No sample was positive for any of the previously identified markers of street heroin use, that is meconine, desmethylmeconine, hydroxypapaverine, and dihydroxypapaverine. When combined with the results from a pilot study the overall specificity approaches 100% with sensitivity of 56%. Conclusions: These findings support the previously indicated high degree of specificity of noscapine and papaverine metabolites for street heroin misuse. While the sensitivity of such testing is less than that of morphine for heroin misuse, we believe that the detection of these markers offers the best currently available means of objectively determining heroin misuse in patients prescribed diamorphine. (Author' s abstract)