Cannabis
THC, CBD, cannabinoids, consumption methods, medical evidence, and the endocannabinoid system — the most nuanced substance guide.
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Overview
Chemical Class: Cannabinoids (C21 terpenophenolic compounds)
Mechanism: THC (delta-9-tetrahydrocannabinol) is a partial agonist at CB1 receptors (primarily CNS — responsible for psychoactive effects) and CB2 receptors (primarily immune system). CBD (cannabidiol) has low affinity for CB1/CB2 but modulates the endocannabinoid system indirectly via FAAH inhibition, 5-HT1A agonism, TRPV1 agonism, and GPR55 antagonism. The endocannabinoid system (ECS) regulates mood, pain, appetite, memory, and immune function via endogenous ligands anandamide and 2-AG.
Schedule: I (federal); varies by state | Risk: moderate
THC vs CBD
| Property | THC | CBD |
|---|---|---|
| Psychoactivity | Yes (intoxicating) | No (non-intoxicating) |
| CB1 binding | Partial agonist | Negative allosteric modulator |
| Anxiety effect | Can increase (dose-dependent) | Generally anxiolytic |
| Pain relief | Yes (direct CB1 activation) | Yes (indirect, anti-inflammatory) |
| Appetite | Stimulates ("munchies") | Neutral or slight suppression |
| Psychosis risk | Increases risk | May be antipsychotic |
| Addiction potential | Moderate (9% of users) | None (WHO report 2017) |
| Legal status (US) | Schedule I (federal); varies by state | Legal if hemp-derived (<0.3% THC; 2018 Farm Bill) |
| Entourage effect | Enhanced by CBD and terpenes | Enhanced by THC and terpenes |
Consumption Methods
| Method | Onset | Peak | Duration | Bioavailability |
|---|---|---|---|---|
| Smoking (joint, pipe, bong) | 1-5 minutes | 15-30 minutes | 1-3 hours | 15-25% |
| Vaporizing (dry herb or concentrate) | 1-5 minutes | 15-30 minutes | 1-3 hours | 50-80% |
| Edibles (food, drinks, gummies) | 30-120 minutes | 2-4 hours | 4-8 hours (can extend to 12+) | 4-12% (first-pass metabolism converts THC to 11-hydroxy-THC, which is MORE potent and crosses BBB more readily) |
| Tinctures (sublingual) | 15-45 minutes | 30-90 minutes | 2-4 hours | 20-35% (sublingual bypasses first-pass) |
| Topicals (creams, patches) | 15-60 minutes | 1-2 hours | 2-4 hours (localized) | Low systemic (localized effect) |
| Dabbing (concentrated extracts) | Seconds | 5-10 minutes | 1-3 hours | 60-90% |