Reports from research centres--16. The National Institute on Drug Abuse (NIDA)

Cognitive-behavioural therapy for substance use disorders in people with psychotic disorders: Randomised controlled trial

BACKGROUND

Few randomised controlled trials have been aimed specifically at substance use reduction among people with psychotic disorders.

AIMS

To investigate whether a 10-session intervention consisting of motivational interviewing and cognitive-behavioural therapy (CBT) was more efficacious than routine treatment in reducing substance use and improving symptomatology and general functioning.

METHOD

A community sample of people with a psychotic disorder and who reported hazardous alcohol, cannabis and/or amphetamine use during the preceding month was recruited. Participants were randomly allocated to motivational interviewing/CBT (n = 65) or treatment as usual (n = 65), and were assessed on multiple outcomes at baseline, 15 weeks, 6 months and 12 months.

RESULTS

There was a short-term improvement in depression and a similar trend with regard to cannabis use among participants who received the motivational interviewing/CBT intervention, together with effects on general functioning at 12 months. There was no differential benefit of the intervention on substance use at 12 months, except for a potentially clinically important effect on amphetamine use.

CONCLUSIONS

The motivational interviewing/CBT intervention was associated with modest improvements.

Permeation of buprenorphine and its 3-alkyl-ester prodrugs through human skin

PURPOSE

Homologous 3-alkyl-ester prodrugs (C2 to C4) of buprenorphine with decreased crystallinity have been synthesized and evaluated for transdermal delivery commensurate with opioid dependence treatment.

METHODS

To assess the influence of derivatization on delivery, the permeation of the prodrugs through human skin was determined in vitro. Prodrug metabolism was measured in human blood and skin supernatant in vitro along with chemical hydrolysis controls. The prodrugs octanol/water partition coefficients were measured.

RESULTS

Without exception, the prodrugs were completely hydrolyzed on passing through the skin and appeared as buprenorphine in the receptor compartment. However, using saturation conditions, in no instance did the buprenorphine flux through skin from a prodrug solution exceed the flux of buprenorphine base itself in vitro. Moreover, the flux of the acetyl ester, the least hydrophobic of the prodrugs, was not significantly elevated upon stripping the skin. Whether in blood or the skin supernatant, the prodrugs hydrolyzed in an apparent first-order fashion and rate constants and half-lives were calculated.

CONCLUSIONS

We conclude from the results that the prodrugs' very high octanol/water partition coefficients (hydrophobicity) placed them in viable tissue layer controlled diffusion. Consequently, one does not derive the potential flux-increasing benefit of reducing crystallinity that was expected.