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Understanding the Mechanism of Smoked Cannabis

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Understanding the Mechanism of Smoked Cannabis

Understand the basic biochemistry that occurs when a person smokes legal cannabis. The most popular, and also most traditional, form of cannabis consumption is smoking. Although other means of consuming the medicinal molecules offered by this unique herb have gained popularity—including vaporization, edibles (including infused beverages), sublingual tinctures, and transdermal patches—for a variety of reasons, scores of consumers and patients continue to prefer to smoke.

A man holds a cannabis joint.
How does smoking pot work?

The act of smoking is an especially social and communal one. The ritualistic act of passing a joint, pipe, or bong has become a trademark of the social side of the cannabis culture. The cannabis community's adherence to smoking to a certain extent illustrates its bohemian roots of self-reliance and a pervasive affinity for low-tech, organic avenues of preparation and consumption.

"The dried cannabis flowers residing in your stash box contain no THC. Instead, they are filled with THCA."

The cannabis culture undeniably holds tightly to the tradition of smoking. Classic culture films such as Up in Smoke and Rolling Kansas embrace the act of smoking loose-leaf marijuana flowers right in their titles! The timeless act of a person mimicking the smoking of a joint, with thumb and forefinger pinched in front of their mouth, is an almost universally recognized physical meme of the 20th century that will probably never die—regardless of the popularity of vape pens, dab rigs, or fast-acting nano-encapsulated drinks.

THC Chemistry Primer

Understanding the Mechanism of Smoked Cannabis. First, a chemistry primer: The dried cannabis flowers residing in your stash box contain no THC. Instead, they are filled with THCA, the acidic precursor analog to THC that is slightly modified when heat or flame is applied (a process called decarboxylation). When one applies a lighter to a joint or bowl full of ground cannabis flowers, the THCA is instantly—and relatively thoroughly—converted to THC.

Smoke wafts from a cannabis joint.
Flame instantly converts THCA to THC.

Chemically speaking, this molecular transmogrification results in only the loss of a carbon dioxide molecule from the THCA compound molecule. Effectively, however, this minor chemical change results in a new molecule that fits perfectly into the CB1 receptors of the body's endocannabinoid system (found mostly in the brain and central nervous system).

It is estimated that 80-90 percent of the THC in raw cannabis is stored in the form of THCA (minor decarboxylation occurs during the drying phase of harvesting via oxidation). When burned or vaped, about 95 percent of the THCA in raw cannabis is converted to THC.

"Physically, both smoking and vaping are the fastest way to get THC and other cannabinoids and terpenes into one's body."

Despite its lack of psychoactive properties, the serious conditions and disease symptoms for which THCA provides relief include insomnia, muscle spasms and seizures, and nausea/vomiting. This makes this cannabinoid effective for cancer patients undergoing chemotherapy and epileptics. THCA also relieves pain, acts as an appetite stimulant (perfect for wasting syndromes and Crohn's disease), and—possibly of most value—is believed to slow or stop the growth of cancerous tumors.

Fastest Route

Understanding the Mechanism of Smoked Cannabis. Physically, both smoking and vaping are the fastest way to get THC and other cannabinoids and terpenes into one's body. When smoke (or vapor) that contains cannabinoids like THC, CBD, and CBN is inhaled, it immediately is absorbed by the lungs and transferred to the neighboring heart, where it is pumped directly north to the brain.

After a sufficient number of CB1 receptors in the brain are filled with THC molecules (the two have what researchers call a strong binding affinity), one begins to feel the psychoactive effects of cannabis in the form of relaxation, euphoria, or pain relief. This entire pathway, from initial inhalation of cannabinoids and terpenes to the feeling of euphoria, takes about 2.5 minutes (although set and setting and personal metabolism play a role).

Medical therapy is gained from both THC and CBD, the former providing much more than simply euphoria. CBD is available in special cultivars of the plant. Cultivars and phenotypes rich in CBD are also available in the form of many products in states that allow legal cannabis sales (including edibles, oils, concentrates, and other extracts or infused products).

Smoking vs. Vaping

Understanding the Mechanism of Smoked Cannabis. Dr. Dale Gieringer of California NORML in 2004 conducted a peer-reviewed research study published in the Journal of Cannabis Therapeutics. The researcher found the vapor produced by the desktop Volcano vaporizer, a pharmaceutical-grade device, to be populated by only THC and trace amounts of CBD and CBN, two other cannabinoids (in some samples, only THC and CBN were detected, with an absence of CBD).

"Our research indicates that vaporization is a promising technology for smoke harm reduction."

Vapor produced by the Volcano vaporizer was completely void of three toxins produced by smoking: Benzene (a known carcinogen), toluene, and naphthalene. Carbon monoxide and smoke tars were also "qualitatively reduced" during vaporization.

Tried & True

Understanding the Mechanism of Smoked Cannabis. Alison Myrden, a patient activist in Ontario, Canada who suffers from chronic progressive multiple sclerosis, can't handle a pipe or bong due to her tremors and neurological condition, which severely hamper her mobility and dexterity. Nor does she enjoy inhaling vapor out of a vaporizer bag or plastic tube.

A woman holds a cannabis joint.
Many patients prefer smoking.

“I'm a joint girl," said Myrden during an exclusive interview, noting how ground and rolled cannabis flower simply works with her physical limitations. While she's used devices such as the pharmaceutical-grade Volcano vaporizer, she continues to cling to smoking flower—often supplemented with kief, hash, or BHO mixed in.

A few years ago, prior to his death in 2010, hemp activist and author of The Emperor Wears No Clothes, Jack Herer, was known for preaching his five second rule to anyone around him who would take notice. If one enjoyed the pleasure of sharing some cannabis with the veteran voice of the hemp movement, there was a good chance they would hear "Five seconds! Hold it for five seconds" as Herer gesticulated with his hand to emphasize his point.

"Holding of one's breath simply is not necessary and does not increase THC absorption rates."

Our time with Herer led to discussions with cannabis industry veterans regarding the need to hold smoke in one's lungs for a few seconds with each toke to maximize bioavailability (absorption of cannabinoids like THC). Many industry vets with whom we spoke claimed that such holding of one’s breath simply is not necessary and does not increase THC absorption rates. Thus, we began inquiring with researchers and doctors.

Dr. Rick Doblin, founder and executive director of the Multidisciplinary Association of Psychedelic Studies, said that he didn't really have an answer, but that he holds in his breath for a few seconds when he smokes. He went on the record saying that he doesn't think the act of holding cannabis smoke in one’s lungs for a brief period is a serious health risk because cannabis is not linked to lung cancer (unlike tobacco smoke).

Doblin also cited how various cannabinoids deliver anti-tumor properties. In other words, if there is any increase in tars or carcinogens from holding in the cannabis smoke, he believes that it is counteracted by cannabinoids like CBD, THC, and CBG.

Getting Down to the Science

Absorption of cannabinoids and terpenes within the lungs is basically immediate (a few milliseconds). During an exclusive interview, Dr. Sunil Aggarwal, a Seattle-based scientist, physician, and cannabinoid integrative medicine specialist said that there is absolutely no need for one to hold their breath to maximize bioavailability of cannabinoids such as THC. In fact, he says this habit causes only harm, not a more potent high.

THC absorption doesn't begin to occur until cannabis smoke passes the first bronchial split from the trachea and has actually entered the lungs. "Human lungs feature the surface area of a tennis court," Aggarwal told us. When cannabinoid and terpene molecules touch this huge surface, they are absorbed in 2-3 milliseconds (that's two to three thousands of a second).

From a human perspective, this process is basically instantaneous. Thus, argue clinical practitioners like Aggarwal, holding one's breath results in achieves nothing more than oxygen deprivation.

A man smokes cannabis.
Do you hold your breath?

Trick to Prevent Wasting Cannabis Medicine

Understanding the Mechanism of Smoked Cannabis. Most of us have wasted a considerable amount of cannabis over the years by executing the inhalation process incorrectly. We realize we risk sounding egregiously nerdy and anal retentive with that statement. Please allow us to explain....

We hesitate to think of the amount of cannabis that we have wasted over the years with our previous sloppy, ignorant toking style. Because of the fact that no smoke in the esophagus above the bronchial split is absorbed, any inhaled that is not pulled below this split is completely wasted. Thus, "big hits" often fill the chamber from the lungs to the mouth, wasting all of the smoke between the bronchial split and the lips (including the nasal passages).

"Ensure that a column of smoke-free air, akin to an invisible plunger, pushes all of the cannabinoid-rich smoke below the bronchial split and into the lungs."

A trick to prevent wasting any cannabis smoke: Ensure that a column of smoke-free air, akin to an invisible plunger, pushes all of the cannabinoid-rich smoke below the bronchial split and into the lungs for full absorption.

How To Do It

Slowly and smoothly inhale, pulling in smoke or vapor for the first two-thirds of the toke. A nice, deep breath also helps ensure that the remote recesses of the lungs are exposed to smoke, which actually improves lung function.

As more research is conducted and humans gain additional insight into the complexities and nuances of the cannabis plant, we'll obviously gain further knowledge into the best methods for consuming and absorbing cannabinoids, terpenes, and flavonoids for medical efficacy and cognitive stimulation.

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