CBD and THC together in the proper ratio and order can either reduce psychoactivity or increase it.
If you’re feeling too anxious from cannabis, taper the buzz with some CBD and THC together. Or, if you want to enhance your high, take some CBD before the THC.
The previous two sentences have practically become mantras among cannabis experts. At first glance, they appear to contradict one another. How can CBD both increase and diminish THC’s intoxicating effects?
The answer, which may or may not be surprising, is that CBD and THC together can do both. As with all things biochemical, it boils down to dose and timing.
It’s Always About Timing
While the science addressing CBD and THC together remains in its infancy, CBD is the most studied cannabinoid after THC. One of the most insightful writings about CBD’s purported effects comes from Brazilian neurologist Dr. Antonio Zuardi in a 2011 letter he co-authored with Jaime Hallak and Jose Crippa for the journal Psychopharmacology.
The paper, titled “Interaction between CBD and THC,” compiled research stretching back to the 1970s that assessed timing and dosing of CBD against THC. Why is Zuardi’s letter important? He noted that his team’s research on CBD and THC “were in ‘notable contrast’” to other researchers’ findings.
Here’s a quick summary of that research regarding time:
- If CBD administered before THC can increase the effects of THC;
- If CBD administered simultaneously with THC increases or inhibits the effects of THC;
- They did not include research studying CBD administration after THC
Unfortunately, all the studies included in Zuardi’s letter only looked at CBD and THC administration in rats and mice. That means, rather than encouraging inhalation or oral consumption, researchers injected the cannabinoids into the test subjects. Furthermore, rodents likely respond to phytocannabinoids differently compared to humans. So this data only gives us clues to CBD’s interactions with THC rather than open-and-shut cases.
CBD First Can Increase Anxiety
But if someone wants to include CBD as a way of reducing THC’s effects – for example, to reduce anxiety – when should they take CBD?
According to the letter, research showed that CBD injected prior to THC administration usually potentiated THC. The effect could be seen anywhere from 20 minutes to 24 hours prior to THC administration, as it typically takes a day for CBD to clear out of the body. Researchers assessed THC’s effects with or without CBD by measuring THC concentrations in the brain, corticosterone (a stress hormone) levels in serum, and running times on wheels.
On the other hand, if CBD and THC were administered at the same time, then CBD could reduce, or antagonize, THC’s effects depending on the dose.C
CBD and THC Together in the Right Dose
As it goes with any biochemical response to drugs, dosing is just as important as timing.
When CBD and THC are taken together, dosing can be reported as a ratio between the two compounds. For example, a 1:1 ratio indicates that the consumer took roughly equal portions of CBD and THC. Many cannabis products that contain both CBD and THC will usually include this ratio somewhere on the packaging.
The most common ratios found in cannabis products are 1:1, 2:1, and 8:1. These ratios may come from Zuardi’s research, as the following details what his team discovered over the years.
- If CBD and THC are administered at the same time at a 1:1 ratio, CBD does not increase, or potentiate, the effects of THC;
- Simultaneous administration at a 2:1 ratio to a 5:1 ratio will potentiate THC’s effects. Zuardi wrote that these ratios produced effects like taking higher doses of THC (8 mg/kg);
- Simultaneous administration at an 8:1 ratio to a 20:1 ratio antagonizes, or inhibits, the effects of THC, similar to taking lower doses of THC (0.25 mg/kg).
Interestingly, CBD given before THC, even at higher ratios (20:1), will actually potentiate THC’s effects. This suggests regardless of the ratio, if CBD goes into the body at least 20 minutes before THC, it will, for whatever reason, increase the effects of THC.
The inhibiting effect on THC only occurs firstly if a rodent received CBD and THC at the same time. Secondly, it was only at a ratio of 8:1 or greater.
Why Does This Happen?
How phyto- and endocannabinoids interact with the body’s endocannabinoid system is still being investigated, and the interactions between cannabinoids, metabolic enzymes, and receptors appear incredibly complex.
However, based on available studies, we know that THC and CBD compete for binding at both CB1 and CB2 receptor sites. Although each phytocannabinoid possesses a greater affinity for binding to one receptor over the over (THC prefers CB1, CBD prefers CB2), either molecule can bind to either receptor type due to their similar chemical structures.
If significantly greater amounts of CBD versus THC enter the body, then CBD will overwhelm THC at CB receptor sites. Furthermore, specific metabolic enzymes (such as those from the cytochrome P series) will also compete to bind THC and CBD that have either failed to bind to CB receptors, or have recently fallen off the receptors. Competition for enzymatic binding and queuing for clearance may explain why CBD administration prior to THC potentiates the effects of THC.
Additionally, CB receptor activation and signaling could contribute to CBD’s ability to either potentiate or inhibit THC’s effects. CB2 receptors regulate immune responses, but their presence in prefrontal cortical pyramidal neurons suggests they regulate neural excitability along calcium and chloride ion channels, too.
Too long, didn’t read? If you want to taper the THC high, balance with CBD. If you want to enhance THC’s effects, take CBD prior to consuming THC.