Short answer
CBG (cannabigerol) is a cannabinoid found in Cannabis sativa. It does not cause a high. In the body, CBG binds the CB1 and CB2 receptors with low affinity. It also acts at TRP ion channels, alpha-2 adrenergic receptors, and the COX-1 and COX-2 enzymes. Data from human trials is thin. Most findings come from cell cultures and rodents.
Step 1: CBG starts as CBGA in the plant
Young cannabis plants build CBGA (cannabigerolic acid). Enzymes then convert CBGA into THCA, CBDA, and CBCA. CBG is the share that is left after that conversion, plus a small amount of CBGA that loses its acid group through heat or light.
Most flower holds less than 1% CBG by weight. Hemp cultivars bred for CBG can reach 10% to 15% total CBG in dried flower.
Step 2: CBG reaches the blood
Inhaled CBG crosses the lung lining. Peak plasma levels after smoking or vaping appear within 3 to 10 minutes. Swallowed CBG passes through the liver first. The liver removes a share of the dose before the rest reaches the body.
what is cbg and what does it do
Step 3: CBG binds its targets
Cannabinoid receptors
CBG has low affinity for CB1, the receptor THC activates to cause a high. Reported Ki values sit in the hundreds of nanomolar range. At CB2, a receptor found on immune cells, CBG acts as a partial agonist.
TRP channels
CBG activates TRPA1, TRPV1, TRPV2, and TRPV3 in lab tests. These channels sit on sensory nerve endings and take part in pain and temperature signaling.
Enzymes and transporters
Brain tissue studies in mice show CBG blocks GABA reuptake. CBG also inhibits COX-1 and COX-2 in vitro. Those tests use concentrations well above the blood levels reached after a normal dose. That gap limits what the results mean for a person.
Adrenergic and serotonin receptors
In lab models CBG acts as an agonist at alpha-2 adrenergic receptors and as an antagonist at 5-HT1A receptors.
Step 4: The liver clears CBG
Cytochrome P450 enzymes handle CBG. CYP2C9 and CYP3A4 take part in the breakdown. Lab work shows CBG can inhibit some CYP enzymes. That raises a theoretical risk of drug interaction. Human data on the size of that risk does not exist yet.
What animal and lab studies show
- Appetite: CBG raised feeding in rats.
- Colitis: CBG reduced colon inflammation in mice.
- Glaucoma: CBG lowered eye pressure in rodent and cat models.
- Bacteria: CBG blocked MRSA biofilm formation in lab dishes.
- Nerve cells: CBG protected neurons in mouse models of Huntington's disease.
- Anxiety: rodent results are mixed.
Human trials on CBG alone are few and small. No CBG medicine holds FDA approval.
Dose and side effects
There is no established dose for CBG. Product labels vary, and measured content often differs from the label. Controlled human trials have not collected side effect data. Common reports from users of hemp-derived CBG include dry mouth and drowsiness. Drug interaction data in humans is absent. Talk to a clinician before mixing CBG with prescription drugs.