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IACM-Bulletin of March 10, 2013

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Science/Human — THC may be detectable in blood of regular cannabis users for weeks, in very low concentrations

THC may be detectable in whole blood in a large number of daily regular cannabis users above a concentration of 1 ng/ml for 12 days and at lower concentrations even up to more than four weeks. This is the result of a study with 30 daily cannabis smokers at the National Institute on Drug Abuse in Baltimore, led by Dr Marylin Huestis, Chief of the Chemistry and Drug Metabolism Section. Participants temporarily lived in a secure research unit for up to 33 days and daily blood samples were taken.

Of the 30 participants, 27 were THC-positive on admission, with a range blood concentration of 0.3-6.3 ng/ml. THC decreased gradually. Only 1 of 11 participants had a blood concentration below 0.3 ng/ml at 26 days and 2 of 5 remained THC-positive (above 0.3 ng/ml) for 30 days, and 5.0% of participants had THC ≥1.0 ng/ml for 12 days. THC-COOH detection rates decreased slowly to 95.7% and 85.7% on days 8 and 22, respectively. 4 of 5 participants remained THC-COOH positive (0.6-2.7 ng/ml) after 30 days. "These data have never been obtained previously due to the cost and difficulty of studying chronic daily cannabis smoking over an extended period," Huestis said in a statement. Authors concluded that “cannabinoids can be detected in blood of chronic daily cannabis smokers during a month of sustained abstinence.”

Bergamaschi MM, Karschner EL, Goodwin RS, Scheidweiler KB, Hirvonen J, Queiroz RH, Huestis MA. Impact of prolonged cannabinoid excretion in chronic daily cannabis smokers' blood on per se drugged driving laws. Clin Chem 2013;59(3):519-26.

UPI of 2 March 2013

News in brief

Science/Human — Tetrahydrocannabivarin (THCV) may offer treatment against diabetes according to clinical study

An article of the IACM-Bulletin of December 2012 on a clinical study was re-written. In the original news THCV was called GWP42004 and CBD GWP42003. Please find here the re-written article.

Science/Human — Cannabis perceived as less harmful than alcohol and tobacco in large survey

According to a large internet survey in three languages on the perceived harms and benefits of 15 commonly used drugs or drug classes, with 5791 individuals from over 40 countries cannabis was ranked consistently beneficial. Alcohol and tobacco fell below many illegal drugs. There was no correlation at all between users' harm ranking of drugs and their classification in the USA and in the UK. Prescription analgesics, alcohol and tobacco were ranked within the top 10 most harmful drugs.

Clinical Psychopharmacology Unit, University College London, UK.

Morgan CJ, et al. J Psychopharmacol. 2013 Feb 25. [in press]

France — Government considers making Sativex available

After several European countries, including the UK, Spain and Germany, have made the cannabis extract Sativex available for patients suffering from spasticity in multiple sclerosis, France is also considering making it available to their citizens. Health Minister Marisol Touraine has asked the agency that regulates pharmaceutical drugs to examine Sativex.

UPI of 2 March 2013

USA — Support for medical cannabis in many states without medical cannabis laws

Most Kentuckians (60%) want to legalize medical cannabis. In Florida as many as seven in 10 voters support a state constitutional amendment legalizing medical cannabis. These are two examples of recent polls on the support of the medicinal use of cannabis in states, where it is not legal, yet.

Miami Herald of 25 February 2013

UPI of 24 February 2013

Science Switzerland — Proceedings of the STCM Conference 2013 available

Proceedings of the Swiss Task Force for Cannabinoids in Medicine (STCM) Conference 2013 "Cannabinoids in Medicine - An Option?" are now available here.

Science/Cells — Cannabinoids reduce multiplication of HIV in blood cells

Cannabinoids, which bind to the CB2 receptor, reduce the multiplication of the HI virus in certain white blood cells (macrophages). Authors noted that “CB2 may offer a means to limit HIV-1 infection in macrophages.”

Temple University School of Medicine, Philadelphia, USA.

Ramirez SH, et al. J Leukoc Biol. 2013 Mar 5. [in press]

Science/Animal — Cannabinoids protect nerve cells in the eye following reduced blood supply

In animal experiments the pressure in the eyes was increased, which resulted in damage to the nerve cells due to reduced blood supply. If a synthetic cannabinoid (WIN55,212-2) was administered to these eyes nerve cell loss was significantly decreased. This effect was mediated by the CB1 receptor.

Department of Cell Biology and Histology. University of the Basque Country, Vizcaya. Spain.

Pinar-Sueiro S, et al. Exp Eye Res. 2013 Feb 20. [in press]

Science/Human — Nabilone decreases cannabis withdrawal

In a study with 11 daily cannabis users the administration of both daily 6 or 8 mg of nabilone, a synthetic derivative of THC, reduced withdrawal symptoms. Authors summarized that “nabilone maintenance produced a robust attenuation of marijuana withdrawal symptoms and a laboratory measure of relapse even with once per day dosing.”

New York State Psychiatric Institute and Department of Psychiatry, College of Physicians and Surgeons of Columbia University, New York, USA.

Haney M, et al. Neuropsychopharmacology. 2013 Feb 26. [in press]

Science/Animal — Cannabinoids reduce traumatic stress by interaction with the glucocorticoid system

It is well-known that cannabinoids reduce symptoms of post-traumatic stress. New research shows that there is an interaction with the glucocorticoid system. Scientists concluded that their findings “suggest that the interaction between the cannabinoid and glucocorticoid systems is crucial in the modulation of emotional trauma.”

Department of Psychology, University of Haifa, Israel.

Ganon-Elazar E, Akirav I. Psychoneuroendocrinology. 2013 Feb 20. [in press]

Science/Animal — CBD improves respiration in an animal model of asthma

In a study with Guinea-pigs the inhalation of a certain substance (ovalbumin) caused constriction of the airways and this was reduced by CBD (cannabidiol). Scientists concluded that CBD “may have beneficial effects in the treatment of obstructive airway disorders.”

School of Life Sciences, University of Hertfordshire, Hatfield, UK.

Dudášová A, et al. Pulm Pharmacol Ther. 2013 Feb 18. [in press]