Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Br J Psychiatry. 2010 Oct;197(4):285-90. doi: 10.1192/bjp.bp.110.077503.

Impact of cannabidiol on the acute memory and psychotomimetic effects of smoked cannabis: naturalistic study: naturalistic study [corrected].

Author information

  • 1Clinical Psychopharmacology Unit, University College London, Gower St, London WC1E 6BT, UK.

Erratum in

  • Br J Psychiatry. 2010 Nov;197:416.

Abstract

BACKGROUND:

The two main constituents of cannabis, cannabidiol and Δ(9)-tetrahydrocannabinol (THC), have opposing effects both pharmacologically and behaviourally when administered in the laboratory. Street cannabis is known to contain varying levels of each cannabinoid.

AIMS:

To study how the varying levels of cannabidiol and THC have an impact on the acute effects of the drug in naturalistic settings.

METHOD:

Cannabis users (n = 134) were tested 7 days apart on measures of memory and psychotomimetic symptoms, once while they were drug free and once while acutely intoxicated by their own chosen smoked cannabis. Using an unprecedented methodology, a sample of cannabis (as well as saliva) was collected from each user and analysed for levels of cannabinoids. On the basis of highest and lowest cannabidiol content of cannabis, two groups of individuals were directly compared.

RESULTS:

Groups did not differ in the THC content of the cannabis they smoked. Unlike the marked impairment in prose recall of individuals who smoked cannabis low in cannabidiol, participants smoking cannabis high in cannabidiol showed no memory impairment. Cannabidiol content did not affect psychotomimetic symptoms, which were elevated in both groups when intoxicated.

CONCLUSIONS:

The antagonistic effects of cannabidiol at the CB(1) receptor are probably responsible for its profile in smoked cannabis, attenuating the memory-impairing effects of THC. In terms of harm reduction, users should be made aware of the higher risk of memory impairment associated with smoking low-cannabidiol strains of cannabis like 'skunk' and encouraged to use strains containing higher levels of cannabidiol.

Comment in

PMID:
20884951
[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk