State lawmakers are moving ahead with legislative efforts to allow for the limited use of medical ‘cannabis’ while simultaneously forbidding anyone from either inhaling the herb or possessing its flowers.
Many medical marijuana advocates cheered the news this week that members of the Utah Senate gave preliminary approval to legislation to permit the use of medical cannabis preparations for qualified patients. No doubt the vote marked a significant change in attitude for lawmakers in the heavily Mormon state. But while the vote marked a ‘first’ for Utah, lawmakers’ decision to prohibit patients from legally possessing, inhaling, or vaporizing actual cannabis is part of a growing, and problematic, national trend.
While no state legislature has approved a law permitting medi-pot patients to grow their own medicine since New Jersey lawmakers banned the practice in 2012, few if any politicians sought to altogether prohibit patients from accessing cannabis flowers (where the majority of pot’s therapeutically active constituents are located) until Minnesota lawmakers addressed the issue last year. In a legislative compromise to appease the state’s Governor, House and Senate lawmakers agreed to amended legislation that, for the first time, mandated patients only be permitted to possess cannabis in non-smoked preparations such as pills or extracted oils (the latter of which could arguably still be vaporized). One month later, New York lawmakers enacted similar legislation restricting the dispensing of medical cannabis only to non-smokeable formulations. And so the trend began.
This legislative session, lawmakers in several states – including Florida, Iowa, Kentucky, Pennsylvania, and Utah are contemplating similar bans on patients’ access to whole plant cannabis and/or their ability to inhale cannabinoid preparations. Of these measures, the proposed Pennsylvania and Utah bills are the most restrictive. They bar patients from possessing cannabis flowers and further prohibit patients from smoking or vaporizing approved medical marijuana preparations. (Under the Pennsylvania plan, cannabis plants must be processed by state-licensed facilities into oils, tinctures, edible products, or ointments before they may be dispensed to qualified patients; Utah’s proposal similarly mandates dispensaries to only provide orally ingestible cannabis preparations to patients.)
Setting aside the practical matter of whether the enforcement of these proposed smoking bans are even feasible, the larger question remains. Is banning flowers in lieu of orally ingested cannabis preparations in the best interest of patients? Here is why it is not.
Oral preparations not fast acting
Patients seeking immediate symptomatic relief from medical cannabis, such as those suffering from conditions associated with migraine, severe nausea, or spasms, are unlikely to find non-inhalable forms of cannabis particularly effective. That is because orally consumed cannabinoids possess a significantly delayed onset of effect compared to inhaled cannabis.
When cannabis buds are inhaled – either via smoking or vaporization – the plant’s biologically active ingredients travel almost immediately from the lungs to the blood stream. They then quickly cross the blood brain barrier and are disseminated throughout the body – where they act on endogenous cannabinoid receptors. This is why subjects that inhale cannabis begin to feel its effects within minutes.
By contrast, cannabinoids present in orally consumed products must first be pass through the stomach and then be metabolized by the liver before ever reaching the blood stream – a biological process that may take some 20 to 30-minutes after the consumption of cannabis tinctures and as long as 60 to 90-minutes following the ingestion of cannabis edibles.
Ingestible preparations are harder to self-regulate
Because of the delayed onset inherent to orally ingested cannabis products, patients have a much more difficult time adequately regulating the substance’s dosing. Patients may wait well over an hour only to discover that they have taken an insufficient dose to provide effective relief. Or, conversely, they may discover that they have consumed a far greater dose than necessary – resulting in prolonged periods of dysphoria. (Orally consumed pot products are also associated with far longer duration of effect as compared to inhaled marijuana.) Proper titration is more readily achieved following inhalation because this administrative route results in the rapid onset of drug effect.
Oral pot preparations possess significant bioavailability
Bioavailability refers to the percentage of an active drug that is absorbed into the body following administration. This percentage is typically influenced by the chosen route of administration. The oral administration of ingestible cannabis products is associated with significantly greater bioavailability than is inhalation – resulting in more pronounced variation in drug effect from dose to dose (even in cases where the dose is standardized). Further, the liver typically converts significant quantities of orally consumed THC to the byproduct11-hydroxy-THC – a psychoactive metabolite that is often associated with increased psychotropic (and sometimes unpleasant) effects. By comparison, inhaled THC is associated with the production of only nominal quantities of 11-hydroxy-THC.
But isn’t inhaling cannabis smoke as dangerous as exposure to tobacco smoke?
Claims that the trend toward medi-pot ingestibles and away from flowers is necessary to address health concerns associated with smoking fail to hold up under scientific scrutiny. For example, a 2005 review published in the Harm Reduction Journal explains that although tobacco smoke and marijuana smoke possess some similar chemical properties, the two substances have different pharmacological activities and are not equally carcinogenic. Specifically, the paper affirms that marijuana smoke contains multiple cannabinoids – many of which possess anti-cancer activity – and therefore likely exert “a protective effect against pro-carcinogens that require activation.” The author concludes, “Components of cannabis smoke minimize some carcinogenic pathways whereas tobacco smoke enhances some.” This conclusion was recently substantiated by a recent review of several large-scale case-control studies published in the International Journal of Cancer in 2014. That paper concluded, "Results from our pooled analyses provide little evidence for an increased risk of lung cancer among habitual or long-term cannabis smokers.”
Other recent scientific assessments of marijuana smoke exposure further report that the two substances possess substantially different effects on pulmonary function. Both a 2012 study published in the Journal of the American Medical Association and a 2015 study published in the Annals of the American Thoracic Society report that the daily inhalation of pot smoke over long-term periods of time is not associated with the sort of adverse effects on the lungs commonly associated with tobacco smoking. “[T]he pattern of marijuana's effects seems to be distinctly different when compared to that of tobacco use," Emory University researchers acknowledged earlier this year.
While tobacco smoking is recognized as a major risk factor for the development of COPD – a chronic inflammation of the airways that may ultimately result in premature death – marijuana smoke exposure (absent concurrent tobacco smoke exposure) appears to present little COPD risk. Writing in the Annals of the American Thoracic Society in 2013, McGill University professor and physician Mark Ware concluded: “Cannabis smoking does not seem to increase risk of chronic obstructive pulmonary disease or airway cancers… Efforts to develop cleaner cannabinoid delivery systems can and should continue, but at least for now, (those) who smoke small amounts of cannabis for medical or recreational purposes can breathe a little bit easier.”
Banning vaporization is irrational
For those patients seeking the rapid onset of cannabinoid effect but who remain cautious about the potential consequences of cannabis combustion, vaporization is an alternate delivery device that has been proven to mitigate smoke exposure. Vaporization heats cannabis flowers or oils to a point where cannabinoid vapors form, but below the point of combustion – thereby reducing consumer’s intake of combustive smoke or other pollutants. Observational studies show that vaporization allows subjects to experience the rapid onset of effect while avoiding many of the associated respiratory hazards associated with smoking – such as coughing, wheezing, or chronic bronchitis. Clinical trials also report that vaporization results in the delivery of higher plasma concentrations of THC (and likely other cannabinoids) compared to smoked cannabis – making it a far more efficient delivery method than either smoking or oral consumption. As a result, scientists affiliated with the University of California Center for Medicinal Cannabis Research and elsewhere now acknowledge that vaporizers provide a “safe and effective” way to for consumers to inhale herbal cannabis.
Science, Not False Assumptions, Should Guide Medi-Pot Policy
Lawmakers’ instincts to demand that medical marijuana be presented and administered in a manner similar to conventional therapeutics may be politically expedient, but is also troublingly naïve. Based on the available scientific record, it makes little sense for lawmakers to promote legislative bans on the possession or inhalation of cannabis flowers. Rather than addressing patients’ needs, these bans unnecessarily limit patients’ choices and deny them the ability to obtain rapid relief from whole-plant cannabis in a manner that has reliably proven to be relatively safe and effective.
By Paul Armentano - NORML/March 5, 2015