Government extinguishes marijuana access, advocates smell politics

Comprehensive Review of Medicinal Marijuana, Cannabinoids, and Therapeutic Implications in Medicine and Headache: What a Long Strange Trip It's Been …

BACKGROUND

The use of cannabis, or marijuana, for medicinal purposes is deeply rooted though history, dating back to ancient times. It once held a prominent position in the history of medicine, recommended by many eminent physicians for numerous diseases, particularly headache and migraine. Through the decades, this plant has taken a fascinating journey from a legal and frequently prescribed status to illegal, driven by political and social factors rather than by science. However, with an abundance of growing support for its multitude of medicinal uses, the misguided stigma of cannabis is fading, and there has been a dramatic push for legalizing medicinal cannabis and research. Almost half of the United States has now legalized medicinal cannabis, several states have legalized recreational use, and others have legalized cannabidiol-only use, which is one of many therapeutic cannabinoids extracted from cannabis. Physicians need to be educated on the history, pharmacology, clinical indications, and proper clinical use of cannabis, as patients will inevitably inquire about it for many diseases, including chronic pain and headache disorders for which there is some intriguing supportive evidence.

OBJECTIVE

To review the history of medicinal cannabis use, discuss the pharmacology and physiology of the endocannabinoid system and cannabis-derived cannabinoids, perform a comprehensive literature review of the clinical uses of medicinal cannabis and cannabinoids with a focus on migraine and other headache disorders, and outline general clinical practice guidelines.

CONCLUSION

The literature suggests that the medicinal use of cannabis may have a therapeutic role for a multitude of diseases, particularly chronic pain disorders including headache. Supporting literature suggests a role for medicinal cannabis and cannabinoids in several types of headache disorders including migraine and cluster headache, although it is primarily limited to case based, anecdotal, or laboratory-based scientific research. Cannabis contains an extensive number of pharmacological and biochemical compounds, of which only a minority are understood, so many potential therapeutic uses likely remain undiscovered. Cannabinoids appear to modulate and interact at many pathways inherent to migraine, triptan mechanisms ofaction, and opiate pathways, suggesting potential synergistic or similar benefits. Modulation of the endocannabinoid system through agonism or antagonism of its receptors, targeting its metabolic pathways, or combining cannabinoids with other analgesics for synergistic effects, may provide the foundation for many new classes of medications. Despite the limited evidence and research suggesting a role for cannabis and cannabinoids in some headache disorders, randomized clinical trials are lacking and necessary for confirmation and further evaluation.

Medical marijuana: tribulations and trials

Widespread use of smoked marijuana in the San Francisco Bay Area as a treatment for HIV-related anorexia and weight loss, as well as nausea related to prescribed therapy, prompted the design of a clinical trial to evaluate the safety and effectiveness of this controlled substance. The Community Consortium--the Bay Area's community-based HIV clinical trials organization--designed a first pilot evaluation of smoked marijuana compared to oral tetrahydrocannabinol (THC, synthesized as dronabinol or Marinol) in 1993. A legal source of marijuana could not be identified. Two subsequent applications to the National Institutes of Health were submitted in 1996 and 1997. During the intervening period, increasing numbers of people with HIV infection were obtaining marijuana for "medicinal use" from local Cannabis Buyer's Clubs. In November 1996, California voters endorsed the medical use of marijuana by approving Proposition 215. The federal government's attempt to oppose the voters' mandate led to public outrage. Organized medicine demanded more studies into marijuana's potential use as medicine. The consortium's 1997 proposal to evaluate the potential interaction between THC and widely-prescribed protease inhibitors was positively received. Funding and study-required marijuana cigarettes have been obtained from the National Institute of Drug Abuse, and the first subjects are being enrolled in the trial. When politically sensitive research proposals include sound science, they can prevail if investigators are willing to persist.

Radiation and chemotherapy injury: pathophysiology, diagnosis, and treatment

The text in general is not meant to represent the participants' entire presentations. The lecture presenters in general are not responsible for the summaries, and cannot necessarily be assumed to agree with all that is stated, but they deserve credit for providing the lecture and handout material on which the summaries are based, and in most cases have contributed far more to the summaries than I have.