Volume 2

Cannabis : the scientific and medical evidence / Select Committee on Science and Technology.

  • Great Britain. Parliament. House of Lords. Science and Technology Committee.
Date:
1998
Catalogue details

Licence: Open Government Licence

Credit: Cannabis : the scientific and medical evidence / Select Committee on Science and Technology. Source: Wellcome Collection.

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    21 April 1998] [ Continued McGuire P K, Jones P, Harvey I, Bebbington P, Toone B, Lewis S, Murray R M (1994) Schizophrenia Research 13: 161-7. Menezes P R, Johnson S, Thornicroft G, et al (1996). Br J Psychiat. 168: 612. Miller P MNcCC., and Plant M (1996). BMJ 313: 394-7. Nahas G G (1975). Medical Aspects of Drug Abuse (Ed R W Richter) Harper & Row, Maryland pp 16-36. Nahas G G (1984). Marihuana in Science and Medicine (Ed G G Nahas) Raven Press, New York, pp 16-36. Nahas G G (1993). Cannabis: Physiopathology, Epidemiology, Detection (Eds G G Nahas, C Latour. CRC Press. National Highway Traffic Safety Administration (1992). Report No DOT HS 808 058. North East Council for Addictions (personal communication). Schwartz R H, (1991). Physiopathology of Illicit Drugs: Cannabis, Cocaine, Opiates (Eds G G Nahas and C Latour). Advances in Biosciences Vol 80, Pergamon Press pp 13-21. Solowij N (1995) Life Sciences 56: 2119-26. Student Counselling Service, Newcastle University (personal communication). Tanda G, Pontieri F E, Di Chiara G (1997) Science 276: 2048-50. Webb E, Ashton C H, Kelly P, Kamali F (1996) Lancet 348: 922-5. Wu T-C, Tashkin D P, Djahed B, Rose J E (1988). New Engl J Med 318: 347-51. Table 1 PREPARATIONS OF CANNABIS (U.S. AND U.K.) Form Source THC content ( this is extremely variable and the figures are approximate ) Marijuana (U.S.) dried leaves/stalks/flowers/seeds Cannabis (U.K.) (Herbal cannabis) traditional cigarette (reefer) of 1960sand 1-3% THC (~10mg/reefer) 1970s modern cigarette (joint) of 1980s—90s result of intensive cultivation and more potent subspecies (sinsemilla, “skunkweed”, “Silver Pearl” and others) Hashish (U.S.) resin secreted by plant Cannabis resin (U.K.) _ bricks, cakes, slabs 10-20% THC Hashish oil product of extraction by organic 15-30% THC (sometimes up to 65%) solvents Table 2 BRAIN AREAS AND FUNCTIONS AFFECTED BY CANNABINOIDS Brain area Functions Cerebral cortex — logical thought, reasoning, judgment Hippocampus — memory functions, time appreciation Limbic system — _ pleasure/reward centres, emotions Sensory areas — perception of sound, colour etc. Motor areas — muscle coordination, balance, psychomotor performance Table 3 CANNABIS EFFECTS LIKELY TO IMPAIR DRIVING AND PILOTING SKILLS Slowed complex reaction time Impaired short-term memory Poor detection of peripheral light stimuli Impaired attention Poor oculomotor tracking Inability to carry out complex or demanding tasks Impaired coordination Poor judgment Size and time distortion Additive effects with alcohol and other drugs Increasing risk taking