Safety Profile of Medicinal Cannabis
Safety is the first concern to be considered for the medical use of cannabis. Cannabis has a remarkably wide margin of safety. Earlier NIDA sponsored animal studies on the harmful effects of cannabis should take into account that most studies were conducted using THC rather than whole cannabis and the doses used were exceedingly high. While the U.S. government warns that cannabis is much stronger (higher THC content) today than in previous times it is important to recognize that dronabinol (synthetic THC in sesame oil) is almost pure THC and yet it has been down-regulated from Schedule II to Schedule III. It is hard to get much stronger than near 100%. Review articles, such as McPartland & Russo (2006) explain that other cannabinoids found in cannabis, such as CBD, can modulate the psychoactive affects of THC. Patients are not as likely to experience the unpleasant psychoactive effects with whole cannabis that occur with the oral use of dronabinol.
There is no claim that cannabis is without potential risk. No medication is risk free to all patients. However, the greatest risks are related to the use of cannabis under marijuana prohibition, such as no quality control, little to no guidance by a healthcare provider, and the potential legal consequences as a result of growing, possessing or distributing this plant. As you read about the potential side effects or adverse reactions, you should note that per numerous patient testimonials, patients have found cannabis to have fewer or milder side effects than their previously prescribed or over-the-counter medications. You will read of patients decreasing or eliminating the use of other medications as they experience the therapeutic effects of cannabis. The 1999 Institute of Medicine’s report concluded that, “The side effects of cannabinoid drugs are within the acceptable risks associated with approved medications.” (p. 127)
Potential pulmonary damage from smoking whole cannabis is often cited as justification for the medical prohibition of cannabis. The leading U.S. researcher in pulmonary effects of chronic marijuana smoking, Donald Tashkin MD, has concluded that long term use does not cause pulmonary damage as was expected. More importantly, smoke can be avoided through use of a vaporizer (see related studies under pulmonary effects). Here again, it is the marijuana prohibition that promotes the smoking risk. Many patients are unaware of vaporizer technology or other delivery forms of cannabis preparations. When recognized as a legitimate medication, healthcare professionals can fulfill their usual role in educating patients about the safe use and administration of this medication to reduce potential risks.
Abrams, D. I., Hilton, J. F., Leiser, R. J., Shade, S. B., Elbeik, T. A., Aweeka, F. T., et al. (2003). Short-term effects of cannabinoids in patients with HIV-1 infection. A randomized, placbo-controlled clinical trial. Ann Intern Med, 139, 258-266.
Hashibe, M., Morgenstern, H., Cui, Y., Tashkin, D. P., Zhang, Z. F., Cozen, W., et al. (2006). Marijuana use and the risk of lung and upper aerodigestive tract cancers: results of a population-based case-control study. Cancer Epidemiol Biomarkers Prev, 15(10), 1829-1834.
Russo, E. B., Mathre, M. L., Byrne, A., Velin, R., Bach, P. J., Sanchez-Ramos, J., et al. (2002). Chronic cannabis use in the Compassionate Investigational New Drug Program: An examination of benefits and adverse effects of legal clinical cannabis. Journal of Cannabis Therapeutics, 2(1), 3-57.
Wang, T., Collet, J. P., Shapiro, S., & Ware, M. A. (2008). Adverse effects of medical cannabinoids: a systematic review. CMAJ, 178(13), 1669-1678.
Grotenhermen, F. (2007) The toxicology of cannabis and cannabis prohibition. Chemistry & Biodiversity. 4:1744-1769. (excellent review article)
Carter, G. T., Weydt, P., Kyashna-Tocha, M., & Abrams, D. I. (2004). Medicinal cannabis: rational guidelines for dosing. IDrugs, 7(5), 464-470.
Frisher, M., Crome, I., Martino, O., & Croft, P. (2009). Assessing the impact of cannabis use on trends in diagnosed schizophrenia in the United Kingdom from 1996 to 2005. Schizophr Res. 113(2-3), 123-128.
Gieringer, D., St. Laurent, J., & Goodrich, S. (2004). Cannabis vaporizer combines efficient delivery of THC with effective suppression of pyrolytic compounds. Journal of Cannabis Therapeutics, 4(1), 7-27.
Hazekamp, A., Ruhaak, R., Zuurman, L., van Gerven, J., & Verpoorte, R. (2006). Evaluation of a vaporizing device (Volcano) for the pulmonary administration of tetrahydrocannabinol. J Pharm Sci, 95(6), 1308-1317.
Mathre, M. L. (2002). Cannabis and harm reduction: A nursing perspective. Journal of Cannabis Therapeutics, 2(3-4), 105-120.
Nutt, D., King, L. A., Saulsbury, W., & Blakemore, C. (2007). Development of a rational scale to assess the harm of drugs of potential misuse. Lancet, 369(9566), 1047-1053.
Nutt, D. (Oct. 2009). Estimating drug harms: A risky business? Eve Saveille Lecture 2009. pp. 1-13. Published by Centre for Crime and Justice Studies, King’s College London. www.crimeandjustice.org.uk (Nutt provides a comparative risk/safety profile of cannabis)
Russo, E. B. (2006). The role of cannabis and cannabinoids in pain management. In B. E. Cole & M. Boswell (Eds.), Weiner’s Pain Management: A Practical Guide for Clinicians.(7th ed., pp. 823-844). Boca Raton, FL: CRC Press.
Tashkin, D. P. (2005). Smoked marijuana as a cause of lung injury. Monaldi Arch Chest Dis, 63(2), 93-100.
Zuurman L, Ippel AE, Moin E & van Gerven JMA. (2008). Biomarkers for the effects of cannabis and THC in healthy volunteers. British Journal of Clinical Pharmacology. 67(1):5-21.Follow Us!