Pharmacokinetic-pharmacodynamic modeling of mood and withdrawal symptoms in relation to plasma concentrations of methadone in patients undergoing methadone maintenance treatment.

The aims of the present study were to characterize the relationship between plasma racemic methadone and its enantiomers' concentrations with respect to their pharmacodynamic effects and to investigate the influence of potential covariates on the pharmacodynamic parameters in patients on methadone maintenance treatment (MMT). Eighty-eight regular subjects at the Sheffield Care Trust Substance Misuse Services were studied. Samples of blood and urine were collected before the daily dose of methadone.

Contribution of the activities of CYP3A, CYP2D6, CYP1A2 and other potential covariates to the disposition of methadone in patients undergoing methadone maintenance treatment.

Aims: To investigate the influence of different cytochrome P450 (CYP) activities and other potential covariates on the disposition of methadone in patients on methadone maintenance therapy (MMT).

Methods: Eighty-eight patients (58 male; 21-55 years; 84 White) on MMT were studied. CYP2D6 activity [3 h plasma metabolic ratio of dextromethorphan (DEX) to dextrorphan (DOR)] was determined in 44 patients (29 male; 24-55 years), CYP1A2 activity (salivary caffeine elimination half-life) in 44 patients (21 male; 24-55 years) and CYP3A activity (oral clearance of midazolam) in 49 patients (33 male; 23-55 years).

Post-treatment outcomes of buprenorphine detoxification in community settings: a systematic review.

A systematic review was undertaken to examine studies of buprenorphine detoxification that has included post-treatment outcomes as well as more immediate aspects of progress. Studies were required to report details of buprenorphine withdrawal regime and post-treatment outcomes including abstinence rates. Only five studies met these criteria, with buprenorphine regimes lasting 3 days to several weeks, and with variable follow-up.

A six-year evaluation of methadone prescribing practices at a substance misuse treatment centre in the UK.

Objectives: To document changes in prescribing practice at a specialized substance misuse service in the UK occurring since the introduction of the 1999 UK National Guidelines on the management of drug misuse, and to explore a possible link between the length of time spent in methadone maintenance therapy (MMT) and the dosage prescribed.

Methods: A retrospective analysis of a computerized prescription database between 1996 and 2002 obtained from Sheffield Care Trust Substance Misuse Service was performed. The relationship between various measures of dosage and the length of time spent in MMT was investigated.

Personality disorder and drug use: a review.

The concept of personality disorder (PD) is more relevant in the clinical management of drug users than other approaches to personality assessment. A problem in diagnosis is separating behaviours inherent in the activity of drug misuse from true evidence of PD, especially the anti-social type (ASPD), and rating instruments vary in their ability to do this. Nevertheless, the available evidence suggests that approximately two-thirds of drug users in treatment have PD, with ASPD the most common.