Cannabinoids and terpenes, with honest evidence ratings
Cannabis contains more than 100 cannabinoids and hundreds of aromatic compounds. Only a few have strong human evidence behind them. This page tells you what each major compound is and, honestly, how much is actually known. Our evidence labels follow the National Academies of Sciences' 2017 review and later FDA actions.
Cannabinoids
| Compound | What it is | What the evidence says | Evidence |
|---|---|---|---|
| THC (delta-9-tetrahydrocannabinol) | The main intoxicating cannabinoid. Acts on CB1 receptors in the brain. | Substantial evidence for chronic pain in adults, chemotherapy nausea (oral cannabinoids) and MS spasticity symptoms, per the National Academies' 2017 review. | Strong for some uses |
| THCA | The raw acid form in fresh and dried flower. Not intoxicating until heated. | Early lab and animal research only. | Limited |
| CBD (cannabidiol) | Non-intoxicating. Works through several receptor systems. | An FDA-approved CBD drug (Epidiolex) treats seizures in Lennox-Gastaut syndrome, Dravet syndrome and tuberous sclerosis complex. Most other claims are not yet proven. | Strong for specific seizure disorders |
| CBDA | The raw acid form of CBD. | Preclinical research only. | Limited |
| CBG (cannabigerol) | The precursor other cannabinoids are made from in the plant. Non-intoxicating. | Mostly lab and animal studies; small human trials are just starting. | Limited |
| CBN (cannabinol) | Forms as THC ages and oxidizes. Mildly intoxicating. | Widely marketed for sleep, but human evidence is thin. | Limited |
| CBC (cannabichromene) | Non-intoxicating minor cannabinoid. | Preclinical research only. | Limited |
| THCV (tetrahydrocannabivarin) | Found in some African-origin strains. Effects differ from THC at different doses. | Small early human studies on appetite and metabolism. | Limited |
| Delta-8 THC | A THC isomer usually made by chemically converting hemp CBD. | Little safety research; the FDA has warned about contamination and accidental poisonings. Most hemp-derived intoxicating products lose federal legal status on Nov 12, 2026. | Unproven |
Terpenes
Terpenes are the aromatic oils that give each strain its smell. They also occur in many fruits, herbs and spices.
| Terpene | Aroma | Research status |
|---|---|---|
| Myrcene | Earthy, musky; also in mango and hops | Common in many strains; popularly linked to sedation, but human evidence is lacking. |
| Limonene | Citrus | Researched for mood in animal studies. |
| Beta-caryophyllene | Pepper, spice | Binds the CB2 receptor in lab studies, unusual for a terpene. |
| Linalool | Floral; also in lavender | Studied for calming effects, mostly through lavender aromatherapy research. |
| Alpha-pinene | Pine | Researched for airway and memory effects in preclinical work. |
| Terpinolene | Fresh, herbal, floral | Dominant in a smaller group of strains. |
| Humulene | Woody, hoppy | Also found in hops; preclinical research only. |
The entourage effect
The entourage effect is the idea that cannabinoids and terpenes work better together than alone. It's widely repeated in dispensaries, and some lab findings fit it, but controlled human studies haven't confirmed it. Treat strain effect claims based on terpenes as a hypothesis, not a promise.
Indica, sativa and hybrid
These labels describe plant shape and ancestry, not reliable effects. Studies of commercial cannabis find that the indica or sativa label doesn't consistently predict chemical makeup. A lab report showing cannabinoid and terpene content tells you more than the label does.
Frequently asked questions
Does CBN help with sleep?
CBN is heavily marketed for sleep, but there is very little human research. Current evidence is limited.
Is THCA legal in Florida?
THCA flower sold at Florida MMTCs is medical marijuana and requires a state card. Hemp-derived THCA products sold outside dispensaries face new federal limits starting November 12, 2026.
What cannabinoid has the strongest evidence?
THC for some types of chronic pain, chemotherapy nausea and MS spasticity, and CBD for specific seizure disorders, where an FDA-approved CBD medicine exists.