IACM-Bulletin of September 12, 2010

Israel — Health Ministry authorizes five more doctors to prescribe cannabis

On 5 September the Health Ministry authorized doctors from five Israeli different hospitals to prescribe cannabis to patients suffering from chronic pain and other severe diseases. So far, there was only one doctor allowed to prescribe cannabis. The ministry is launching a pilot program meant to increase the number of doctors allowed to prescribe cannabis for medicinal purposes. The ministry estimates that in 2010 there will be an increase of 66 percent in the permits for cannabis, allowing treatment for about 5000 patients. In future, the ministry expects tens of thousands of patients to be treated with cannabis.

Most prescriptions for cannabis are given to patients suffering from chronic pain, including patients with fibromyalgia and cancer, but also to patients with HIV/AIDS, neurological disorders, multiple sclerosis, asthma and glaucoma, as well as to veterans suffering from post-traumatic stress disorder. Until now, 14 Israeli farms have been given permits to grow cannabis legally for medicinal use, but only three are currently operating. The health ministry recently approved a monthly fee of 360 Shekels (about 75 Euros, about 95 US Dollars) per cannabis user to cover growing expenses. Israel is obligated by international treaty to establish a government agency regulating the distribution of cannabis for medicinal purposes, but has not done so.

More at:

http://www.haaretz.com/news/national/israel-relaxes-restrictions-on-medical-marijuana-1.312347

(Source: Haaretz of 5 September 2010)

Science — Smoked cannabis effective in chronic neuropathic pain

A clinical study was conducted at McGill University in Montreal, Canada, with 23 patients suffering from neuropathic pain caused by trauma or surgery. They were randomly assigned to receive cannabis at four potencies (0, 2.5, 6 and 9.4 per cent THC) over four 14-day periods in a crossover trial. Participants inhaled a single dose through a pipe three times daily for the first five days in each cycle, followed by nine-days without treatment. Daily average pain intensity was measured using a scale from 0 to 10. "This is the first trial to be conducted where patients have been allowed to smoke cannabis at home and to monitor their responses, daily," said Dr. Mark Ware, lead author of the study.

Of the 23 participants 21 completed the trial. The average daily pain intensity was significantly reduced by the cannabis of highest potency compared to placebo cannabis (5.4 and 6.1). Preparations with intermediate potency yielded intermediate but non-significant degrees of relief. Participants receiving cannabis with 9.4 per cent THC also reported significantly improved ability to fall asleep and improved quality of sleep. There were no differences in mood or quality of life. Researchers concluded that "a single inhalation of 25 mg of 9.4% tetrahydrocannabinol herbal cannabis three times daily for five days reduced the intensity of pain, improved sleep and was well tolerated."

More at:

- http://www.reuters.com/article/idUS32351+30-Aug-2010+PRN20100830

- http://www.winnipegfreepress.com/canada/breakingnews/smoking-cannabis-can-relieve-some-pain-improve-sleep-clinical-trial-101773538.html

The complete study is available at:

http://www.cmaj.ca/cgi/rapidpdf/cmaj.091414v1

(Sources: Reuters of 30 August 2010; Canadian Press of 29 August 2010; Ware MA, Wang T, Shapiro S, Robinson A, Ducruet T, Huynh T, Gamsa A, Bennett GJ, Collet JP. Smoked cannabis for chronic neuropathic pain: a randomized controlled trial. CMAJ. 2010 Aug 30. [in press])

Canada — Cannabis extract Sativex approved for the treatment of spasticity due to multiple sclerosis

According to a press release of 31August by GW Pharmaceuticals, the manufacturer of Sativex, a cannabis extract containing equal amounts of THC and CBD, the Canadian Health Ministry approved the extract for the treatment of spasticity in patients suffering from multiple sclerosis. Canada is the third country after the UK and Spain to approve Sativex for this indication.

"Sativex is useful as adjunctive treatment for symptomatic relief of spasticity in adult patients with MS who have not responded adequately to other therapy and who demonstrate meaningful improvement during an initial trial of therapy," the company said. In addition to this new approval, Sativex is available in Canada for the symptomatic relief of neuropathic pain in adult patients with multiple sclerosis since 2005 and as adjunctive analgesic treatment in adult patients with advanced cancer who experience moderate to severe constant pain despite the highest tolerated dose of strong opioids since 2007.

More at:

http://www.gwpharm.com

(Source: Press release by GW Pharmaceuticals of 31 August 2010)

News in brief

Science — HIV

At the Columbia University in New York, USA, 7 HIV-positive patients who regularly used cannabis received THC (dronabinol) in a placebo-controlled cross-over study. In two 16-day periods they received either 10 mg THC four times a day or placebo. THC increased caloric intake and sleep quality in the initial 8 days of dosing. THC's mood-enhancing effects were sustained across the 16 days. Researchers concluded that "selective tolerance" was observed to the appetite and sleep enhancing effects. (Source: Bedi G, et al. Psychopharmacology (Berl). 2010 Sep 8. [in press])

Science — Ecstasy and THC

Scientists of the University of Nijmegen, The Netherlands, investigated differences between the effects of inhaled THC in combination with ecstasy (MDMA) and of both drugs alone in 16 healthy volunteers. THC was administered by a vaporizer. Co-administration of THC with MDMA increased desired subjective drug effects and drug strength compared with ecstasy alone, which according to the authors may explain wide-spread combined use. (Source: Dumont G, et al. J Psychopharmacol. 2010 Sep 3. [in press])

Science — Appetite

According to research at Fukuoka University, Japan, animals who received a high-fat diet for three days preferred a high-fat diet thereafter. This effect was mediated by the CB1 receptor. The concentration of the endocannabinoid 2-AG was increased in the hypothalamus after three days of high-fat diet. (Source: Higuchi S, et al. Behav Brain Res. 2010 Sep 1. [in press])

Science — Widening of the arteries

According to research at a university in Madrid, Spain, the synthetic cannabinoid methanandamide caused relaxation of the aorta in rats and this effect was mediated by CB1 and CB2 receptors. Further investigation showed that NO (nitric oxide) and cytochrome P450 enzymes are involved in this relaxation of this artery. (Source: López-Miranda V, et al. Cardiovasc Drugs Ther. 2010 Sep 4. [in press])

Science — Diabetes

According to research at the Medical College of Georgia in Augusta, USA, cannabidiol (CBD) protects nerves of the retina. This was in part due to the prevention of glutamate accumulation by action on responsible enzymes. (Source: El-Remessy AB, et al. Mol Vis 2010;16:1487-95.)