This is the second installment in a three-part series on the topic of medical cannabis. Read the first article here.
Cannabis as Medicine
The health benefits of medical cannabis have been reported since 2737 B.C., when Chinese Emperor Shen Nung began to record its uses. These possible medical uses include the following:
- assists in decreasing nausea, vomiting, and pain, increases appetite, assists patients with insomnia, produces short-term reduction of intraocular eye pressure, has anti-anxiety properties, decreases spasticity, tremor, rigidity, and seizures, may assist in decreasing inflammation, decreases symptoms of PTSD;
- treatment of these symptoms is beneficial for patients with HIV/AIDS, multiple sclerosis, cancer, movement disorders (e.g. Dravet syndrome, [4/15/2014 Edit: Dravet syndrome is an epileptic condition, not a movement disorder.] possibly useful for treating Parkinson’s disease symptoms, etc.), anorexia (the symptom, not anorexia nervosa which is a psychologically-based eating disorder), glaucoma, arthritis, some gastrointestinal disorders such as Crohn’s disease, and more.
More than 60 U.S. and international health organizations support use of medical cannabis under a physician’s supervision, including the American Academy of Family Physicians, Lymphoma Foundation of America and multiple AIDS organizations including the AIDS Action Council.
Mechanism of Action: Cannabis contains over 400 compounds, over 60 of which are unique to the plant and are known as “cannabinoids.” Three of the main cannabinoids are THC (tetrahydrocannabinol), CBD (cannabidiol), and CBN (cannabinol). The entire plant compound is necessary in order to receive full therapeutic benefits, and this phenomenon is known as the “entourage effect.” In the body, cannabinoids attach to cannabinoid receptors (CB1 and CB2) which are found in the nervous system, connective tissues, organs, glands, immune system and related locations. The body also produces its own endogenous cannabinoids (anandamide and 2-AG), which interact with these receptors. Cannabinoids help to maintain homeostasis, assist in stabilization of nerve cells, can help to prevent inflammatory responses, and more. There is still a large amount of research that needs to be conducted on cannabinoids and the cannabinoid system in order to fully understand its function.
Health risks due to medical cannabis use are minimal. Medical cannabis does not cause brain atrophy, even after extended use, if use begins in adulthood. It’s a good option to be used in concert with other medications in order to reduce the chance of dependence on medications with a high potential for dependence (such as codeine) and to decrease the risk of tolerance to certain medications. Medical cannabis use may not work optimally for every patient who has an “eligible” disorder, but this is also true for many other commonly accepted medications and remedies.
Cannabis has never resulted in a death from overdose (unlike many other medications), because it is a virtually impossible occurrence. With THC potency of approximately two to four percent, one would have to smoke approximately 900 cannabis cigarettes in order to have a 50 percent chance of death, which is 100 times the amount smoked in one sitting by the heaviest chronic users. However, cannabis does have the potential to exacerbate symptoms of underlying conditions, such as certain cardiac issues, so use is only recommended under supervision of a health care provider who understands the patient’s full medical history.
Health Benefits of Vaporizing Rather than Smoking: Vaporizers are a type of inhalation delivery device for medical cannabis. Vaporizers function by heating cannabis only enough to release cannabinoids in water vapor (at approximately 338 degrees Fahrenheit), rather than to the approximately 800 degrees Fahrenheit or higher temperature needed for cannabis to burn (which is typical for smoked cannabis). Vaporizers are therefore able to prevent the release of (and in some cases, filter out) harmful substances from cannabis smoke, as well as prevent heat damage to the lungs. For example, one study showed that vaporizers, such as the Volcano, can reduce the amount of carcinogenic polynuclear aromatic hydrocarbons (PAH) inhaled when medical cannabis is vaporized rather than smoked. Other studies have shown that vaporization of medical cannabis is less harmful to the lungs that smoked cannabis. Cost is an issue in the use of vaporizers, as they are significantly more expensive than devices used to smoke medical cannabis. However, due to the fact that patients have ranked vaporizers as the most efficient method of delivery for medical cannabis use, a lower amount of medical cannabis may be needed per patient over time for those who use a vaporizer. In this case, lower medication costs due to a decreased quantity needed over time may eventually make up for the cost of the vaporization device. For the health benefits, purchase of a high-quality vaporizer is worth the cost.
Mental Health and Medical Cannabis: A large number of the scientific studies that claim that medical cannabis has a detrimental health impact have led people to infer that cannabis use causes schizophrenic and psychotic symptoms. However, medical cannabis does not cause mental illness, and a recent study conducted at Harvard Medical School shows that cannabis use does not cause schizophrenia specifically. Due to the fact that some cannabis users with mental disorders such as depression or psychotic mental disorders choose to self-medicate with cannabis, and to the fact that certain psychotic illnesses may be exacerbated by cannabis use, results of these studies which supposedly support the fact that medical cannabis causes psychotic disorders and schizophrenia have severe confounding variables. Therefore, they do not provide valid evidence that cannabis causes psychotic symptoms in patients. In addition, only approximately 3 percent of the U.S. population have a psychotic mental disorder. However, due to the possible exacerbation of psychotic mental illness that medical cannabis can cause, these studies do assist in identifying another reason why medical cannabis should only be used under prescription and supervision by a physician, who is aware of the patient’s full physical and mental health history.
Problems: Four to nine percent of people who use cannabis develop problems with work or relationships as a result of use, abuse or dependence. These problems can be caused by issues which result from the use of cannabis or to issues which result from stigma associated with the substance. Although the term “addiction” in relation to cannabis is frequently used, the terms “dependence” or “abuse” are more appropriate. Addiction relates to “compulsive drug-seeking behavior,” and physical dependence “is normal and can occur in anyone who takes medications that affect the CNS [central nervous system].” Dependence can be psychological or physiological/physical, and one can become psychologically dependent on almost anything, including video games, food, and pornography. Although the risk for physical dependence does exist, withdrawal symptoms are very mild, especially in relation to other illicit and dependence-inducing FDA-approved medications, and include anxiety and irritability. To understand the true “addiction” potential of cannabis, it may be helpful to note that cannabis is less technically “addictive” than nicotine , alcohol and caffeine .
Potency: As of 2008, average THC potency in cannabis has increased from one to five percent from the 1970s through 1990s, to approximately 8.52 percent as of 2009. However, there is currently no evidence that increased potency leads to higher rates of dependence or increased negative health effects. For medical conditions that can be benefited by THC, higher potency may actually lead to less smoking of medical cannabis, which can preserve lung function and reduce chances of other negative health effects related to smoked medical cannabis use. Regulated medical cannabis sales would also limit potency of medical cannabis to accepted and standardized doses. Additionally, various cannabinoid ratios can be produced in the plant through breeding in order to optimally treat varying disorders. For example, low THC/high CBD (cannabidiol) medical cannabis can be formulated for certain conditions, such as Dravet syndrome.
Medications that have been formulated with components of medical cannabis (such as dronabinol or marinol) are inadequate in comparison to the full plant compound.
- THC in the absence of other cannabinoids can be extremely anxiety-inducing;
- other cannabinoids in cannabis, such as cannabidiol (CBD) and cannabinol (CBN), produce many of the health benefits of medical cannabis;
- synthetic compounds can be expensive in comparison to the plant, depending on dosage (due to laboratory research and formulation, distribution, and marketing costs, etc.);
- effects are felt much more slowly, and dosage is therefore more difficult to control for the patient, than in smoked or vaporized form.
Health Risks: Despite its comparatively clean record, cannabis is not a completely harmless plant. Cannabis with psychoactive effects, with a THC potency of at least one percent, may temporarily impair areas of the brain, such as the frontal cortex, which is responsible for planning, memory, inhibitory control, cognition speed and behavior coordination. Some sensitive tests have shown that severe chronic use of cannabis can affect select functions of the brain negatively long-term, although others have shown no such long-term impairments or have shown that such impairments are reversible with abstinence. Smoking cannabis chronically over several years can cause damage to the lungs and a decrease in lung function. Smoking burnt plant material can cause respiratory tract cell abnormalities, which may lead to cancer, although no evidence to date has shown a definitive link between cancer development and cannabis use. While cannabis and tobacco smoke contain many of the same carcinogens, some research has suggested that nicotine in tobacco promotes these carcinogenic effects, while THC found in cannabis counteracts them. Even with the possible beneficial effects of THC, cannabis smoke does still contain carcinogens. However, measures can be taken to reduce the possible negative long-term impacts of medical cannabis use, such as avoidance of severe chronic use, use of vaporized medical cannabis, and use of medical cannabis in edible form. Cannabis should never be used by children in a recreational manner, due to its potential to interrupt proper brain development if use begins in childhood. However, it may prove helpful for some children with severe medical conditions, such as Dravet syndrome, which currently lack other effective treatments and which may prove to be more harmful to the child’s health than the use of medical cannabis.
As a reminder, all medications have negative side effects, many of which are worse than the side effects of medical cannabis use. According to the 1999 medical cannabis report produced by the Institute of Medicine (IOM), “For certain patients, such as the terminally ill or those with debilitating symptoms, the long-term risks [associated with smoking] are not of great concern … except for the harms associated with smoking, the adverse effects of marijuana use are within the range of effects tolerated for other medications.” According to a recent study led by UCSF and the University of Alabama at Birmingham, at moderate levels of use, and partially due to differences in frequency of use between smoked cannabis and smoked tobacco, smoking medical cannabis is less likely to result in decreased lung function than smoking tobacco. Due to possible decreased pulmonary function associated with heavy smoking of medical cannabis, medical cannabis treatment should be properly balanced between a standard inhalation (smoking), vaporization, and oral administration regimen.
Drug Scheduling, Research Impeded, and Economic Factors
“Schedule I drugs, substances, or chemicals are defined as drugs with no currently accepted medical use and a high potential for abuse. Schedule I drugs are the most dangerous drugs of all the drug schedules with potentially severe psychological or physical dependence.”
The scheduling of cannabis makes performing research on the substance extremely difficult, which limits accurate knowledge of its positive and negative effects. Due to this scheduling, when medical cannabis use is allowed in special circumstances, like for research), the federal government only allows the use of cannabis grown on federal farms (there is currently only one, located in Mississippi, which therefore limits access and increases transportation costs for the medication) or that has been confiscated by the police (which has unknown potency, quality and the possibility of being laced with other substances such as cocaine).
Research Limits: A controlled, randomized trial is the most effective research method available to obtain valid information on the efficacy of medical treatments. While some of these trials have been conducted with the cannabis plant, limited research options (due to the Schedule 1 classification of cannabis in the United States) have led to a large amount of evidence being gathered as case studies, anecdotal evidence, or through the testing of synthetic THC and not the full plant compound. Due to cannabis needing no laboratory reformulation to be effective medically, there is little incentive for pharmaceutical companies to increase research because there is minimal profit to be made. The lack of profit availability therefore decreases the amount of research performed.
Also, to allow for use of medical cannabis, it must outperform other medications in order to be considered effective, even if it is as effective as or slightly less effective than another medication which has worse side effects This is called “non-inferiority” testing. Opponents of medical cannabis prescription legalization have used these limits in research to justify prevention of medical cannabis legalization. While an increase in research is essential to understanding the full impact of cannabis on various physiological processes, and the classification of cannabis in the United States must be modified in order to allow such research to be completed, enough valid research has been conducted in order to allow medical cannabis use for certain conditions. Preventing use of this medication, especially with the current insufficient scientific evidence to support such prohibition, will cause millions of patients in the United States to continue to suffer unnecessarily with debilitating symptoms.
Cost: A medical cannabis program has the potential to be inexpensive to maintain, and even the potential to generate profits for states and the federal government. While money will need to be spent on creating and maintaining production and distribution of medical cannabis, jobs will be created, economic development will be promoted, and decreased law enforcement costs are likely to result. From mid-2011 to mid-2012, the medical cannabis program in Arizona generated $5.5 million more than was spent to maintain the program. Cannabis also has the potential to be a relatively inexpensive option on an individual patient level. To increase appetite and treat the symptom of anorexia, it has been suggested that 0.5 to one cannabis cigarette (one cannabis cigarette is equivalent to 0.5 g of smoked cannabis) or 0.25 g of vaporized cannabis be used before each meal. Estimating three meals per day, this is equivalent to 0.75 g to 1.5 g of smoked cannabis per day or 0.75 g of vaporized cannabis per day. At one of the top-rated dispensaries in Los Angeles, California (where medical cannabis is legal), the most expensive medical cannabis is $360 per ounce. There are 28.3495 grams in one ounce. Therefore, using 0.75 g to 1.5 g of cannabis per day would cost $9.53 to $19.05 per day for smoked cannabis or approximately $9.53 per day for vaporized cannabis out-of-pocket. While this may be more expensive than some patients can afford (especially since some patients may need more than 1.5 g of medical cannabis per day and prices may be higher in other locations), there are other options. For example, for the least expensive medical cannabis at the dispensary described above ($150 per ounce), the cost would approximate from $2.65 to $7.94 of smoked cannabis per day or approximately $2.65 per day for vaporized cannabis out-of-pocket. In addition, lawmakers in Washington, D.C. (where medical cannabis is legal) have recently attempted to instate mandatory discounts on medical cannabis for low-income patients. As medical cannabis becomes more widely accepted for its medicinal uses in the medical and legal communities, moves such as this to increase practical access for patients of all socioeconomic levels will likely become more frequent. Although medical cannabis is currently not covered under insurance policies, this will hopefully change with increased research and acceptance of cannabis as a medicinal substance. Additionally, for many patients who suffer from pain, anorexia symptoms, insomnia, nausea, movement disorders, PTSD, and more, relief is priceless.
Prescription Medication Issues: It is important, now more than ever, to research and utilize alternatives to dangerous prescription medications. Every day, 100 Americans die from drug overdose. In 2008, the majority of these overdoses were caused by approved prescription medications. As mentioned previously, this would not be a worry with medical cannabis, as death as a result of accidental overdose of cannabis is virtually impossible. A new medicine called Zohydro, which is marketed for chronic pain, has recently been approved by the FDA. Zohydro is a hydrocodone-based medication that is 5 to 10 times more potent than Vicodin and lacks acetaminophen, which is occasionally added to certain addictive medications in order to help to deter abuse, due to its potential to cause liver damage. Zohydro has a high potential for abuse, and may result in many overdose deaths. Zohydro’s approval signals an obvious significant need for alternative medications to what is currently available for conditions such as chronic pain. Recent research has shown that commonly prescribed medications lack effectiveness for chronic pain. It is therefore important that alternative methods be explored. Zohydro’s approval also shows that there is much more involved in the approval of new medications than just scientific evidence and human welfare, which are too often not at the forefront of such decision-making.
The following is a quote from Dr. Sanjay Gupta, a neurosurgeon and CNN’s chief medical correspondent, who in the past was in opposition to medical cannabis, but now supports its use for certain conditions:
“I apologize because I didn’t look hard enough, until now. I didn’t look far enough. I didn’t review papers from smaller labs in other countries doing some remarkable research, and I was too dismissive of the loud chorus of legitimate patients whose symptoms improved on cannabis. Instead, I lumped them with the high-visibility malingerers, just looking to get high. I mistakenly believed the Drug Enforcement Agency listed marijuana as a schedule 1 substance because of sound scientific proof. Surely, they must have quality reasoning as to why marijuana is in the category of the most dangerous drugs that have “no accepted medicinal use and a high potential for abuse.” They didn’t have the science to support that claim, and I now know that when it comes to marijuana neither of those things are true. It doesn’t have a high potential for abuse, and there are very legitimate medical applications. In fact, sometimes marijuana is the only thing that works.”
The third and final installment of “Medical Cannabis: A Matter of Patients, not Politics” on March 31 will discuss organizational and patient/caregiver support of medical cannabis, as well as what you can do to help advocate for legalization of medical cannabis prescription in the United States.
Thank you to Dr. Mitch Earleywine, PhD, who authored the main reference of this article and also provided additional feedback.
Thank you to Will Jaffee for being the editor of this article, and to the entire staff of in-Training.
Thank you to Gretchen Gunn, Steven Obrzut, Alex Sadasivan, Elizabeth McIntosh, Eric Martin Nyberg, and Eric Brown for their assistance in the Compassionate Care advocacy group on Medical Student Advocacy Day in January 2014. Thank you also to Phyllis Ying for her help as leader of the public health advocacy group, and to her, Ajay Major, and Xin Guan for their organization of Medical Student Advocacy Day.
Author’s note: The views expressed in this article are those of the author and do not necessarily represent the views of, and should not be attributed to, Albany Medical College, Albany Medical Center, in-Training, or any affiliated organization.