The same milligram is not the same dose. Swallowed, it arrives in thirty to ninety minutes, lasts six to twelve hours, and roughly four to twelve percent of it reaches your bloodstream, after the liver has converted much of the THC into a metabolite that is stronger than what you took. Inhaled, the same milligram arrives in seconds, lasts two to three hours, and ten to thirty-five percent reaches you intact. Those are not two doses of one drug. They behave like two different medicines.
The route pulls three levers at once: how fast the drug arrives, how long it stays, and how much of it the liver gets to first. Inhaled routes are fast, short and visible, so you can see the effect and stop. Oral routes are slow, long and blind, so overshooting is easy and irreversible for hours. Topicals stay local and barely enter the bloodstream at all.
Pick the route for the system you are aiming at, then set the dose. Not the other way round.
Speed. Inhalation puts the drug in within seconds to minutes. Oral takes thirty to ninety. That difference decides whether a patient can feel what is happening and respond to it, or has to commit and wait.
Duration. Two to three hours inhaled, six to twelve hours oral. For breakthrough pain, the short one is the feature. For overnight coverage, the long one is.
What the liver gets first. This is the lever people miss. Swallow THC and it passes through the liver before it reaches circulation, and much of it becomes 11-hydroxy-THC, which crosses into the brain more readily than THC itself. The ratio approaches one to one. That is why an edible feels different in kind, not just in timing, and why the same number on the label lands harder.
| # | Route | Onset | Duration | Bioavailability | First-pass | Interaction load |
|---|---|---|---|---|---|---|
| 1 | Inhaled, smoked flower | Seconds to minutes | 2 to 3 h | 10 to 35% | Low | Moderate, high flag for CYP1A2 drugs |
| 2 | Inhaled, dry-herb vaporiser | Seconds to minutes | 2 to 3 h | 10 to 35% | Low | Moderate, lower than smoked |
| 3 | Inhaled, oil or concentrate vape | Seconds to minutes | 2 to 3 h | High | Low | Moderate, plus overshoot caution |
| 4 | Sublingual or oromucosal oil | 15 to 45 min | 4 to 8 h | Between oral and inhaled | Partial | Moderate |
| 5 | Tincture, held in the mouth | 15 to 45 min | 4 to 8 h | Partial | Partial | Moderate |
| 6 | Digestible oil, swallowed | 30 to 90 min | 6 to 12 h | 4 to 12% | Maximal | High |
| 7 | Digestible edibles | 30 to 90 min | 6 to 12 h | 4 to 12% | Maximal | High |
| 8 | Tincture, swallowed | 30 to 90 min | 6 to 12 h | 4 to 12% | Maximal | High |
| 9 | Topicals: creams, balms, salves | Local, slow systemic | Prolonged, low | Very low systemic | None | Low |
| 10 | Transdermal patch | Slow | Prolonged | Low, steady | Low | Low to moderate |
| 11 | Suppository, rectal | Slow, variable | Not characterised | Not characterised | Unknown | Unknown, its own risk tier |
Two honest notes on that table. Route 11 is genuinely not characterised in humans to a standard I would quote, and I would rather say so than fill the cell. And route 3 delivers high bioavailability in a single breath, which is exactly why overshoot is easy with it.
| The goal | Target system | Reach it with | What it spares |
|---|---|---|---|
| Local pain or inflammation, a joint or the skin | Peripheral CB2 and TRPV1 in the tissue | Topical | The central nervous system and the liver entirely |
| Fast breakthrough relief, acute pain or panic | CB1 in the CNS, quickly | Vaporised inhalation | Combustion, and the CYP1A2 induction with it |
| Overnight or steady coverage | Systemic CB1, sustained | Oral, minding the liver, or a patch | Oral spares nothing metabolically; the patch spares the peaks |
| Steady daytime baseline with minimal peaks | Systemic, low peak concentration | Transdermal patch | Sharp peaks, and the acute interactions that ride them |
| Any patient on three or more interacting medicines | Whichever the goal is | Prefer topical or vaporised, avoid oral unless necessary | First-pass enzyme competition |
The principle underneath the table: aim at the system, not the milligram. The route decides which systems get hit hardest, and the system you never meant to touch is often exactly where the risk was hiding.
Three things stack. The onset is slow enough that a patient concludes nothing is happening and takes more. The first-pass conversion to 11-hydroxy-THC means what eventually arrives is stronger than what was swallowed. And the duration is long enough that a mistake cannot be waited out in twenty minutes.
There is a fourth, quieter one. Food changes the dose. Taken with a consistently high-fat meal, absorption can rise roughly four to five times. A patient who moves from taking an oral dose on an empty stomach to taking it after dinner has not changed their dose on paper. They have changed it in practice, substantially.
So the coaching rule for any oral route is the two-hour rule: take it, write down the time, and do not take more until two hours have passed. It is unglamorous and it prevents most of the bad evenings.
This is the part I most want a patient to take away. A route change is not a convenience change.
Treat each of those as starting a new medicine, because that is how your body is treating it.
This is education, not treatment, diagnosis or prescription. I am not a doctor, physician, clinician or prescriber. I hold two Israeli Ministry of Health licences: as a patient from 2004, and from 2008 as the first Medical Cannabis Instructor licensed in Israel, a licence to educate and coach rather than to prescribe.
Cannabis treats nothing. Patients report outcomes, and those reports are worth taking seriously and worth writing down. Dose, route and anything touching another medicine belong with your prescriber.
Thirty to ninety minutes, with effects lasting six to twelve hours. That is slower and longer than inhalation, which arrives in seconds to minutes and lasts two to three hours. The slow onset is what catches people out: it is long enough to conclude nothing is happening and take more, and by the time both doses arrive the mistake cannot be waited out. The practical rule for any swallowed dose is to write down the time and take nothing further for two hours.
Because swallowed THC passes through the liver before reaching your circulation, and much of it is converted to 11-hydroxy-THC, which enters the brain more readily than THC itself. The ratio approaches one to one. So an edible is not simply a slower version of the same dose, it delivers a different and more potent compound. Oral bioavailability is lower, roughly four to twelve percent against ten to thirty-five percent inhaled, but what arrives hits harder.
Topicals carry the lowest interaction load, because very little reaches the bloodstream and nothing meaningful passes through the liver first, so a cream aimed at a joint spares both the central nervous system and liver enzymes. Vaporised inhalation is next, and avoids the CYP1A2 induction that combustion causes. Oral routes carry the highest load because first-pass metabolism is maximal. For a patient on three or more interacting medicines, changing the route lowers risk before the dose is adjusted at all.
Yes, substantially. With a consistently high-fat meal, absorption of an oral dose can rise roughly four to five times. The number on the label does not change but the amount reaching you does. If you take an oral dose, keep meals consistent, and treat a change in that routine as a change in dose, especially if you are near an interaction threshold.
I will not recommend it, because it is not characterised to a standard worth quoting. Onset is slow and variable, and bioavailability has not been properly established in humans. It sits in its own risk tier for that reason. Where the evidence is absent I would rather say so than fill the gap with a confident-sounding number.
The course that accompanies the book opens with its first module free and complete: three videos, about twenty-eight minutes, and no pharmacology at all. It is the method you then use on everything else, mine included. It is also where I say out loud that I taught a fixed twenty-eight day tolerance reset from stage for years, went looking for the study behind the number, found that it does not exist, and stopped teaching it.
No card, no call. The rest of the course is paid, and by then you will have seen exactly how I teach.
Watch module one free
Gil Luxenbourg