chapter ten
What should we tell our patients about marijuana?
Joseph Pizzorno
Contents
Exogenous toxins
Endogenous
Toxins of choice
Cannabis (marijuana)
Toxicity in unadulterated cannabis
Contaminants
Pesticides
Solvents
Heavy metals
Microbial
Synthetic cannabinoids
Detoxification
Clinical indications of toxicity
Intervention
Conclusion
References
Long-time readers Integrative Medicine—A Clinician’s Journal are well aware of the many editorials I have written on how a growing body of research is showing that toxins have become a major cause of chronic disease. As I study toxicity, my understanding has broadened to include not only environmental metals and chemicals but also endogenously produced toxins such as those from homocysteine, gut bacteria, and nonoptimally detoxified hormones. To this list I now add what I call “toxins of choice.” Few of our patients are intentionally exposing themselves to neurotoxic organophosphate pesticides, endocrine-disrupting polychlorinated biphenyls (PCBs), insulin receptor site-blocking phthalates, or lung-damaging mold from damp buildings. However, many of our patients are intentionally consuming known toxins such as alcohol and marijuana and are unlikely to realize that at modest dosages salt, high-fructose corn syrup, phosphates, and nonsteroidal anti-inflammatory drugs (NSAIDs) are toxic as well. Added to this that by also considering genetic susceptibility, even sources of gluten can be toxic. The huge load of environmental, endogenous, and choice toxins adds up to deplete stores of protective glutathione and cause physiological and structural damage in many ways.
The following is my current list of many toxins that stress physiology and cause disease in our patients.
Exogenous toxins
•OTC and prescription drugs
•Chemicals: inorganic, organic, fluoride, persistent organic pollutants, solvents
•Metals: arsenic, cadmium, lead, mercury
•Microbial
•Mold (damp buildings)
•Particulate matter
•Radiation: light at night, medical, cell phone
Endogenous
•Catecholamines (if COMT SNP)
•Gut-derived toxins
•Homocysteine
•Non-end product metabolites
•Poorly detoxified hormones
Toxins of choice
•Alcohol
•Marijuana
•Food constituents
•High-fructose corn syrup
•Phosphates
•Salt
•Smoking
•Wheat (if zonulin is produced)
Cannabis (marijuana)
Although the federal government has classified cannabis as a controlled substance illegal for use, many states have now decriminalized its use. Twenty-four states and the District of Columbia have passed laws allowing medicinal use of marijuana, and 14 states have decriminalized its use. The percentage of Americans who say they have tried marijuana has steadily increased from 4% to 43% in 2016 [1].
Cannabis production has become a multibillion dollar industry in the United States, and legal markets for cannabis are projected to reach $11 billion by 2019 [2]. The federal illegality of cannabis has resulted in not only limited clinical research but also a production environment with few standards and very little regulation. As most is currently grown indoors, heavy use of agricultural chemicals is common. Toxicity may be due to not only constituents of marijuana itself but also contaminants such as solvents, pesticides, and heavy metals, with most extracts adding solvent residues. This likely helps explain some of the discrepancies in the research.
Toxicity in unadulterated cannabis
Almost 500 compounds have been extracted from cannabis, of which 65 are classified as cannabinoids. The most abundant cannabinoids include delta-9-tetrahydrocannabinoic acid (THCA), cannabidiolic acid (CBDA), cannabigerolic acid (CBGA), and their decarboxylated derivatives delta-9-tetrahydrocannabinol (THC), cannabidiol (CBD), and cannabigerol (CBG) [3]. These compounds are converted into their more active decarboxylated counterparts by heat (smoking, evaporation, baking), light, or natural degradation. THC is the most psychoactive component of cannabis and alters cognition primarily through the activation of CB1 receptors on presynaptic axons, though several other mechanisms have been identified [4,5]. The content of THC in marijuana has increased from 3.1% in 1992 to 5.1% in 2002 [6,7].
THC itself has low toxicity, and modest use has shown minimal long-term physical or psychological effects when not used to excess [8,9]. Acute high-dose intoxication occurs quickly but is short term. Typical symptoms include nausea, anxiety, paranoia, short-term memory loss, confusion, and disorientation [10]. THC impairs gonadal function by blocking gonadotropin-releasing hormone (GnRH) release. This results in lower levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which causes reduced testosterone production by the testicular Leydig cells [11].
The research on the toxicity of whole plant marijuana is inconsistent, probably due to lack of control for contaminants, poor assessment of dosage, small sample size, limited number of heavy users, mode of use, and not adjusting for other factors such as alcohol, tobacco, and other recreational drugs [12].
The method of use significantly affects the toxicity of marijuana. The most common use is inhalation of the smoke of the dried plant. This results in higher ...
