Even though 16 states and the District of Columbia have legalized medical marijuana, multiple obstacles remain before its use is widely accepted. Despite the evidence of benefits in certain conditions, the use of medical marijuana within a legal jurisdiction still faces a number of challenges, as noted in a number of recent medical articles. Medscape recently listed several of the problems inherent in the medicalization of marijuana.
- Method of Delivery and Quality Control. Smoking raw cannabis remains the most common and easiest route of delivery, but the actual amount of cannabinoids deliverable to the lungs varies considerably depending on the individual’s techniques of inhalation/exhalation, the percentage of aeroingestion, and the individual’s functional lung capacity. Without prior training, it could be difficult for a family physician or psychiatrist in daily practice to advise an eligible patient on the proper techniques of administration and quality control of prescription regarding medical marijuana. The content of THC in cannabis may vary remarkably according by geographic origin, the parts of plant being used (buds versus stem and seeds), the methods of storage, and the techniques of cultivation. There are 2 main strains used in medical marijuana: the Sativa and the Indica. The Sativa plant is usually taller with longer leaves that grow better outdoors, whereas the Indica plant is more bushy with shorter leaves that thrive better indoors. Although both strains exist in pure forms, various combinations of the 2 strains are packaged as medical marijuana, which may result in variable therapeutic and side effects. Health Canada’s policy of adopting a centralized source of medical marijuana from an approved plantation is a good way to assure quality; however, it is still technically difficult to endorse it globally for all licensed users and growers. As a prescription, standardization and titration of dose efficacy remain a challenge for medical marijuana.
- Adequate Monitoring and Prevention of Addiction. As with other substances of abuse, cannabis may lead to varying adverse effects and addiction potential among different individuals. Before facilitating an eligible person to receive medical marijuana, family physicians and psychiatrists should possess the knowledge and skills to screen for addiction potential. During the course of treatment, close surveillance of the patient to prevent addiction and adverse effects, in collaboration with a specialist when necessary, remains a top priority. In Canada and in those American states where it is legal to use medical marijuana, more training and educational resources should be made available for the practicing family physician and psychiatrist to enhance their competence in approaching cannabis.
- Contaminants in Cannabis. Studies have reported an alarming level of biological contaminants in cannabis, which include Aspergillus fungus and bacteria, potentially leading to fulminant pneumonia, especially among the immunosuppressed. Nonbiological contaminants also have been found, which include heavy metals from soil like aluminum and cadmium, the latter of which seems to be absorbed by the cannabis plant in particularly high concentrations. Organophosphate pesticides are other nonbiological contaminants that are found less in cannabis cultivated outdoors than indoors. Finally, tiny glass beads or sand have been found in street samples of cannabis, which were added for weight to boost profits and can cause damage to the oral mucosa and lungs.
- Contamination by Cannabis. Secondary inhalation of cannabis fumes released by primary smokers is a theoretical but negligible threat, as shown by a study of airborne particulates in urban Spain and another study of passive exposure to cannabis smoke in a Netherlands coffee shop. More research in this area is warranted from the perspective of public health.
As noted above, issues such as standardization of treatment and safety remain. The risks and benefits need to be carefully weighed before medical marijuana becomes a nationally recognized standard of treatment for various conditions.
