CBG does not appear to help with nausea. In fact, the available preclinical evidence suggests CBG may actually work against nausea relief, particularly if you’re also using CBD. This is a case where the science tells a more complicated story than the marketing around CBG products would have you believe.
What the Research Actually Shows
The key study on CBG and nausea tested both rats and shrews, two standard animal models for studying nausea and vomiting. When researchers gave animals CBD at 5 mg/kg, it effectively suppressed nausea-related behavior in rats and vomiting in shrews. But when they pretreated the animals with CBG before giving CBD, the anti-nausea effects of CBD were reversed. All tested doses of CBG (1, 5, and 10 mg/kg) blocked CBD’s benefits.
CBG also blocked the anti-nausea effects of a well-known serotonin receptor activator called 8-OH-DPAT, confirming the finding wasn’t just about CBD specifically. The conclusion from this research, published in Psychopharmacology, was direct: moderate doses of CBG and CBD oppose one another in regulating nausea and vomiting.
Why CBG and CBD Have Opposite Effects
The reason comes down to how each compound interacts with a specific serotonin receptor called 5-HT1A. This receptor plays a significant role in the brain’s nausea response. CBD activates this receptor, which is one of the main ways it produces its anti-nausea effects. CBG does the opposite: it blocks this same receptor.
When both compounds are present, CBG essentially cancels out what CBD is doing at that receptor. Think of it like one person pressing the gas while the other presses the brake. Interestingly, at very low concentrations, CBG may slightly stimulate this receptor, but at the doses that have been studied, its blocking action dominates. This distinction matters because most CBG products on the market contain doses that would fall into the antagonist range.
While CBG has been described as having “antiemetic” properties in some review articles, the direct experimental evidence points the other direction. The original reference cited for CBG’s antiemetic potential actually demonstrated that CBG interfered with anti-nausea pathways rather than supporting them.
What This Means if You Use Full-Spectrum Cannabis Products
Many cannabis products contain both CBD and CBG together, especially full-spectrum extracts. If you’re using these products specifically for nausea, the CBG content could be reducing the anti-nausea benefits you’d get from CBD alone. The ratio between the two cannabinoids likely matters, though researchers haven’t pinpointed an exact threshold where CBG stops being a problem.
If nausea relief is your goal, a CBD isolate or a product with minimal CBG content would be a more logical choice based on current evidence. This runs counter to the popular “entourage effect” idea that more cannabinoids working together always produces better results. For nausea specifically, these two cannabinoids appear to work against each other.
CBG’s Side Effect Profile
One thing CBG has going for it is a mild side effect profile, at least in the short term. A double-blind, placebo-controlled human trial found that only a small percentage of participants reported any side effects: dry mouth (16.5%), sleepiness (15%), increased appetite (12%), and dry eyes (9%). CBG did not produce the intoxication or cognitive impairment associated with THC. Notably, nausea was not reported as a side effect of CBG itself in this trial, though the study also wasn’t designed to measure nausea specifically.
Potential Drug Interactions
CBG is processed in the body by several of the same liver enzymes that metabolize a wide range of common medications. Specifically, CBG interacts with CYP3A4 and CYP2D6, two of the most important drug-metabolizing enzymes in the body. If you’re taking prescription anti-nausea medications or other drugs processed by these enzymes, CBG could potentially alter how those medications work by competing for the same metabolic pathways. This is especially relevant for people managing chemotherapy-induced nausea, who are often on multiple medications simultaneously.
No Approved Medical Use
The FDA has not approved CBG, or any cannabis-derived product other than a few specific prescription medications, for treating nausea or any other condition. CBG products sold as supplements cannot legally claim to treat nausea, and the agency has issued warning letters to companies making therapeutic claims about cannabinoid products. The products available over the counter have not been tested for purity, accurate dosing, or effectiveness in the way prescription drugs are.
For people dealing with persistent nausea, the current science does not support reaching for CBG. If anything, it suggests being cautious about CBG content in products you might already be using for nausea relief, since it could be undermining the benefits of other cannabinoids like CBD.