[Cannabis] appears to be effective for many types of pain, but also has added beneficial effects, including anti-inflammatory effects, and help with sleep, appetite, and mood. —Greg Carter, MD
Explore This IssueSeptember 2019
Of particular interest to the otolaryngology community, the committee also determined there is some, or “moderate,” evidence of no statistical link between cannabis use and head and neck cancer incidence. They defined “moderate” evidence as several findings from good- to fair-quality studies with very few or no credible opposing findings, with a general conclusion possible but with the limitation that chance, bias, and confounding factors can’t be ruled out with reasonable confidence.
The committee’s first two recommendations were to address research gaps and improve research quality. “This is a pivotal time in the world of cannabis policy and research,” committee members wrote. “Shifting public sentiment, conflicting and impeded scientific research, and legislative battles have fueled the debate about what, if any, harms or benefits can be attributed to the use of cannabis or its derivatives.”
The published literature on marijuana and cannabinoids in otolaryngology specifically is extremely thin. Earlier this year, researchers at Temple and Drexel Universities published a report on their search of the entire English literature available on PubMed, using a laundry list of otolaryngology search terms (Am J Otolaryngol [published online ahead of print May 30, 2019]. doi: 10.1016/j.amjoto.2019.05.025). They found just 79 unique publications. Most were published in the last decade and related to head and neck cancer. The researchers found a small number of studies suggesting cannabis may be useful for otolaryngology patients with blepharospasm, effects of radiation, and the psychological effects after getting a cancer diagnosis. “Further research is required to determine the potential therapeutic roles and adverse effects of cannabis on conditions related to otolaryngology,” researchers wrote.
Rafi Kabarriti, MD, assistant professor of radiation oncology at Montefiore Health System and Albert Einstein College of Medicine in New York, is one of the few researchers currently conducting research involving medical marijuana in otolaryngology. He is investigating its feasibility and potential benefits for patients with head and neck cancer undergoing chemoradiation. “Our motivation for this is that, first, our patients really struggle, as do all patients, undergoing radiation and chemotherapy for head and neck cancers,” he said. “We try to get these patients through these necessary treatments to get them through their cancer.”
The primary question is, “How easy is it to get medical marijuana in New York City for our patients?” he said. It seems like a rudimentary question, but even the accessibility is not well understood.
“I’ve treated a number of patients with head and neck cancer who have used cannabis, but not through a legal pathway, and what I’ve noticed in those patients is that they seem to tolerate treatment better than the ones who are not using cannabis through whatever means,” he added. The pilot study, with an enrollment goal of just 30 patients, will only include tinctures or the pill form of cannabis because of the concern that smoking or vaping could cause a burning sensation or exacerbate the side effects.
Greg Carter, MD, president of the American Academy of Cannabinoid Medicine and clinical professor at Washington State University Elson S. Floyd College of Medicine in Spokane, said that there are still misconceptions about medical marijuana. “I think a lot of healthcare providers still think cannabis is a dangerous drug with no medical benefits,” he said. “That simply is not true. Cannabis is not a cure-all and certainly does have side effects. However, if it is used under medical supervision, it can be remarkably helpful for many conditions.”
Some researchers say that CBD alone doesn’t produce much beyond a placebo effect, and that THC, a cannabinoid with psychoactive effects, is needed to produce a traditionally therapeutic effect. Dr. Carter said that’s an area that also needs more inquiry. “I think we need to do more research on CBD and some other cannabinoids, including CBN [cannabinol],” said Dr. Carter. “However, there is some evidence that THC works better and is less intoxicating when it is in the presence of other cannabinoids.”
Cannabis use in the treatment of pain, epilepsy, and cancer is among the most prominent areas of research now. Overall, he said, the research base for cannabis is “pretty massive.”
“However, a lot of that work is studies done in animals,” he said. “There are a lot of human studies, but mostly with THC. Still a lot of work needs to be done with CBD and the many other cannabinoids.”
In his view, he said, the most important thing for physicians to know about medical marijuana in order to best treat their patients is that “cannabis does appear to be safe from a pharmacological perspective.”
“It appears to be effective for many types of pain, but also has added beneficial effects, including anti-inflammatory effects, help with sleep, appetite, mood, among many other beneficial effects,” Dr. Carter said.