title: A urinalysis-based study of buprenorphine and non-prescription opioid use among patients on buprenorphine maintenance.
abstract: OBJECTIVE
  To understand the pattern of use of opioid-substitution therapy (OST) and opioid abuse among patients on buprenorphine maintenance using urinalysis.
  
  
  METHODS
  The study was conducted at a tertiary care de-addiction center. We reviewed the laboratory record of all consecutive urine samples sent for drug analysis over a period of 1 year. In all, 179 consecutive urine samples were included in the analysis. The chi-square test was used to compare opioid abuse among those testing positive and negative for buprenorphine on urinalysis. Additionally, in order to assess the potential impact of the prescribed induction and maximum dose of buprenorphine on the findings, we carried out the independent-samples t test. Level of statistical significance was kept at P<0.05 for all the tests.
  
  
  RESULTS
  Urinalysis failed to detect buprenorphine in 44.7% of the samples. Rate of detection of dextropropoxyphene was significantly higher among buprenorphine-negative samples (P<0.005). The prescribed induction dose of buprenorphine was significantly lower among those testing positive for heroin. This was found for both buprenorphine-positive (P<0.005) as well as buprenorphine-negative samples (P<0.005).
  
  
  CONCLUSIONS
  These findings support the routine use of urine drug screening among individuals on OST.
authors.affiliation: Department of Psychiatry and De-addiction, Lady Hardinge Medical College and SSK Hospital, New Delhi, India.
authors.forename: Yatan Pal Singh
authors.initials: YP
authors.lastname: Balhara
authors.forename: Raka
authors.initials: R
authors.lastname: Jain