There's a big difference in the action of THC when it's ingested vs. inhaled
In terms of the metabolic pathway that THC takes through the body. Most are aware that the liver breaks down the main psychoactive ingredient delta-9-THC into other molecules. First, enzymes turn delta-9-THC into 11-Hydroxy-THC which is very psychoactive, and then into 11-Carboxy-THC which is minimally psychoactive as it's the last stage of metabolism.
When we inhale cannabis this action occurs much more quickly than it does when we ingest. For some this makes ingestion the opportune route for long term pain management and other type of therapeutic use for health reasons as it will last longer in the system, but the ultimate therapy for most patients comes when the delivery methods are combined - both ingestion and inhalation.
There's science behind the reason why.
While inhalation offers cannabis patients quick relief due to the nearly instantaneous metabolism of THC, ingestion gives a long lasting relief to the many ailments in which high THC cannabis and it's extracts offer -especially the analgesic effects that reduce opioid and other pharmaceutical consumption or will often replace some pharmaceutical medications for responsible patients.
When THC/Cannabis is ingested, delta-9-THC slowly enters the bloodstream through the walls of the stomach and intestines, often taking anywhere from 30 mins. on up to an hour to metabolize and give the user the feeling of being medicated. When THC is absorbed through a gastrointestinal or ingested delivery, delta-9-THC travels first to the liver where, depending on the unique physiology of the user, either some or even much of it is eliminated or metabolized before it has ever had a chance to activate a receptor in our brain. Ingestion of THC is much more prone to activate the CB-2 Cannabinoid Receptors throughout our bodies than it is to activate CB1 in the brain. After the first pass through the liver, the remaining delta-9-THC and both its metabolites get to the heart and from there into circulation. Delta-9-THC and 11-Hydroxy-THC reach the brain simultaneously but in a much more subtle way than when inhaled. Quickly the benefits of ingestion are understood as well as the benefits of inhalation as they both offer a patient a different type of therapy.
Breaking the stigma of smoking and inhalation
By using both routes of medicating it also breaks the cycle of pain which is the goal in my own case after ceasing 24 years of strong pharmaceutical opioid use.
There's two distinctly separate metabolic actions that occur within our endocannabinoid system and I'm looking for both of them. Inhalation is a short term solution where ingestion gives a much longer period of relief. Sometimes with pain we need immediate analgesic effects and that's not going to happen by ingestion alone for most of us. There are other routes of delivery including topical, sublingual, trans dermal, and rectal - all of which are very effective as well depending on the type of therapy needed. Trans-dermal patches allow a trickle effect of delivery much like any other patch that comes from the pharmaceutical industry.
The use of suppositories by cancer and other cannabis patients has increased over the years as the knowledge spreads in regards to the first pass of the liver, as well as knowledge that by using this route of delivery causes more of the cannabinoids to make their way into the Endocannabinoid System without being metabolized like they are with ingestion.
Ultimately the route of delivery is determined by the patient and what they're most comfortable with. As the role of the physician in cannabinoid medicine advances, it's of high hopes that patients will learn more from trusted sources instead of following the direction of a friend on the internet.