IACM-Bulletin of July 22, 2001

Science — Discussion on the medical value of cannabinoids in British Medical Journal

Two review articles of historical data on the efficacy of cannabinoids in pain and chemotherapy-induced nausea published in the British Medical Journal of 7 July received much media interest.

The review by Dr. Fiona A Campbell and colleagues concluded that "cannabinoids are no more effective than codeine in controlling pain (...)." The review by Dr. Martin R Tramèr et al. said that "in selected patients, the cannabinoids tested in these trials may be useful as mood enhancing adjuvants for controlling chemotherapy related sickness. Potentially serious adverse effects (...) are likely to limit their widespread use." In a commentary Dr. Elsa Kalso of the University of Helsinki expressed doubts whether there is need in cannabinoid-based drugs.

Dr. Roger Pertwee of the University of Aberdeen said in an interview: "The data reviewed in the BMJ paper are the same as those we reviewed in the report of the British Medical Association on cannabis published in 1997. This report recommended that the prescription of cannabinoid medicines should be permitted for patients with intractable pain."

In a letter to the editor Dr. Franjo Grotenhermen of the Cologne Nova-Institute noted that pooled data "will miss much of the interesting information, particularly differences in efficacy for different conditions (...) The question of interest is not whether cannabinoids are potent analgesics compared to codeine but in which painful conditions cannabinoids are effective."

Dr. Philip Robson of GW Pharmaceuticals said: "GW agrees with the authors of the paper that post-operative pain is not the area in which cannabinoids are likely to provide superior therapeutic benefit over existing treatments. (...) However, the paper also recognises that cannabis could be useful in other areas of pain, in particular neuropathic pain and spasticity, and it is these areas in which GW is focusing its current research."

(Sources: Campbell FA, et al. BMJ 2001;323:13; Tramèr MR, et al. BMJ 2001;323:16; Kalso E. BMJ 2001;323:2-3; http://www.gwpharm.com/; Grotenhermen F. Letter to the editor of 19 July 2001)

Science — News at the 2001 meeting of the ICRS (II)

Below are some more research results presented at the annual meeting of the International Cannabinoid Research Society (ICRS) from 28 to 30 June in Spain. (See also the last IACM-Bulletin.)

(1) THC and other cannabinoids prevented programmed cell death (apoptosis) induced by ceramide in nerve cells (astrozytes). This effect was CB1 receptor mediated. (Abstract by Teresa Gómez del Pulgar, et al.)

(2) Pilot studies with a cannabis extract in the UK with two female patients suffering from chronic back pain and sciatica and with two female multiple sclerosis patients demonstrate the variable responsiveness to a treatment with cannabis. One of the patients with back pain achieved substantial reduction of pain while there was only some improvement in sleep in the other. The two MS patients also showed marked differences with regard to benefit and side effects. (Two abstracts by William Notcutt, et al.)

(3) The cannabinoid receptor antagonist SR141716 had antidepressant effects in an animal model of depression. Mice were suspended by applying adhesive tape near the end of the tail and their behaviour was studied. (Abstract by Richard E. Musty, et al.)

(4) Endocannabinoids are important for normal food intake in newborn mice, which can be disturbed by the antagonist SR141716. The inhibition of neonatal food intake and growth by the antagonist is mostly a result of specific CB1-receptor blockade. (Abstract by Ester Fride, et al.)

(5) The analgesic properties of THC (20 mg) and morphine (30 mg) alone and in combination in healthy subjects were tested. THC did not significantly reduce pain in the tests. Some analgesic effects were only observed in combination with morphine. (Abstract by Rudolf Brenneisen, et al.)

(6) The activation of peripheral CB2 receptors produced antinoception to thermal stimuli. CB2 receptor agonists may have promise for the treatment of pain without causing central CB1 mediated effects. (Abstract by T. Philip Malan, et al.)

CORRECTION: In the last IACM-Bulletin a study by Hagenbach et al. was presented. Erroneously it was stated that THC decreased the overactivity of the bladder sphincter. Actually THC decreased the overactivity of the bladder muscle (detrusor).

(Source: Program and abstracts of the 2001 ICRS Symposium on the Cannabinoids)

News in brief

Canada — Pharmacists are prepared

Alberta pharmacists say they are prepared to distribute cannabis for medicinal purposes, if there is a supplier. "We would approach it the same as any other drug," said Greg Eberhart of the Alberta College of Pharmacists. The college is urging the profession to learn about proper doses, side effects and potential interactions. (Source: Calgary Herald of 19 July 2001)

USA — Colorado/Kaiser Permanente

Attorneys for Kaiser Permanente in Colorado have given its doctors a tentative green light to endorse medical use of cannabis for qualified patients. Doctors sought legal advice from the lawyers of the organisation in recent weeks after they became concerned about facing prosecution. Under state law, doctors must sign official documents stating that their patients could benefit from using marijuana. Kaiser Permanente is America's largest not-for-profit health maintenance organization, serving 8.1 million members in several states. (Sources: Denver Rocky Mountain News of 7 July 2001, http://www.kaiserpermanente.org/)

UK — Poll on cannabis

A poll published on 8 July said a growing number of Britons were in favour of cannabis being legalised. A poll for the Independent on Sunday newspaper reported that 37 percent of Britons wanted the drug legalised with 51 percent opposed. In 1996 66 percent were against legalising cannabis, and just 26 percent in favour. The poll comes two days after Peter Lilley, a right-winger of the conservative party, who was minister in the cabinets of former Prime Ministers Margaret Thatcher and John Major, said cannabis should be legalised. (Source: Reuters of 7 July 2001).