Why Does the 1:1 CBD:THC Ratio Work So Well?

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Shanti Ryle - Content Writer

Jul 13 2021 - 5 min read

Today, we’re looking at what’s special about the 1:1 ratio of CBD: THC. Many medical marijuana patients find this ratio nothing short of miraculous. But why? This article dives into some studies into the ratio and why it’s effective.

In addition to reading this article, we recommend that you speak to your physician while you’re applying for your medical marijuana card to get a personalized dosage recommendation.

Table of contents
      1. Sativex and the Initial GW Pharmaceuticals Studies
      2. How Do THC and CBD Interact?
      3. What About the Other Cannabinoids?
      4. How Do the Effects of Different CBD:THC Ratios Vary?
      5. A Quick Note on the “Psychoactivity” of Cannabis
      6. Conclusion
    Download Our 1 Pager Guide to Dosing Medical Marijuana

    To be clear, the “best ratio” of cannabinoids varies from person to person and condition to condition. For example, some types of cancer require high amounts of THC to treat properly, while other types of cancer require more cannabidiol (CBD) than THC, especially with conditions like estrogen-positive breast cancer. Age, gender, and even weight can also affect the individual’s response to specific cannabinoids in particular ratios. You can learn more about different cannabinoids and terpenes in our handy table.

    However, for many people, the magic ratio of THC to CBD is 1:1. In this article, we explore the existing evidence to find a few reasons why.

    Sativex and the Initial GW Pharmaceuticals Studies

    In the UK, GW Pharmaceuticals produces a product named Sativex, which contains a THC: CBD ratio of approximately 1:1. In their development research, the company found that  the participants of the initial studies reported a preference to the 1:1 ratio, claiming it to be the most tolerable while still helping to prevent or reduce pain, stiffness, and spasms. Users today report that the 1:1 ratio also produces fewer psychoactive effects, making everyday life tasks more feasible and free from fogginess.

    Cannabis vs. Prescription and OTC Medications

    Sativex is the trade name for nabiximols. A systematic review in 2014 by the American Academy of Neurology found that nabiximols was ‘probably effective’ for spasticity, pain, and urinary dysfunction, but wasn’t supported for tremors. Naboximols was also helpful in treating cancer pain resistant to opioids, but the Phase III study did not meet its primary endpoint. While Phase II trials showed that cannabis was effective for cancer-related pain, Phase III trials did not. This suggests that further and deeper research still needs to be done.

    Is Sativex Available for Patients in the US?

    No, Sativex is not available on prescription for patients in the US because of its failure to pass Phase III trials. You can, however, get a medical marijuana card and purchase a 1:1 THC:CBD product.

    Is Epidiolex Available for Patients in the US?

    Epidiolex is a CBD-based drug that is available for prescription in the US, also made by GW Pharmaceuticals. It is used to treat seizures associated with Lennox-Gastaut syndrome or Dravet syndrome in patients aged 2 and older. Epidiolex is a Schedule V drug, as the FDA approved it and it contains less than 0.1% THC.

    However, CBD derived from cannabis flower is still a Schedule I drug and not approved by the FDA. Only CBD derived from hemp is legal, and any product made using it will need to contain 0.3% or less of THC for it to remain legal. Aside from Epidiolex, there are no other CBD products that have received FDA approval.

    How Do THC and CBD Interact?

    relax if you've had too much cannabis
    THC and CBD balance each other out

    CBD seems to “balance” out the high THC causes when used in equal ratios to each other, while allowing the THC to provide its own pain-killing, antiemetic and appetite-stimulating properties. THC and CBD seem to work in tandem with each other, and can possibly even bolster each other’s strengths while buffering some of THC’s psychoactivity.

    Researchers theorize that because CBD does not cross the blood-brain barrier (BBB) and is a partial antagonist of the CB1 receptor, THC helps CBD pass the BBB and allow it to work more effectively. This is just a theory, however, and one that doesn’t explain the full relationship between CBD and THC. However, research has found some evidence of a relationship between CB1 receptors in the brain and the gut and CB2 receptors found on immune system cells.

    The ins and outs of how various cannabinoids and terpenoids interact is not precisely known, but it seems CBD may prolong THC’s presence in the liver while regulating THC’s intoxicating effects when used in a 1:1 ratio.

    This could be why many high-THC, low-CBD strains’ effects can be potent but don’t usually last long. Such strains also tend to contain tetrahydrocannabivarin (THCV), which blocks THC in low doses and has its own intoxicating effects at high doses. The lack of CBD and high amounts of THC and THCV may give a clue as to why there is no “ceiling” to this type of plant. High-THC, high-CBD strains tend to last longer but tend to leave people relatively nonfunctional.

    Download Free Guide to CBD
    Download Free Guide to THC

    What About the Other Cannabinoids?

    CBD and THC are far from the only cannabinoids that affect the body. We also ought to take into account the other cannabinoids in our cannabis, as they all contribute to the overall effect.

    Terpenes and terpenoids also play a role in the Entourage effect and deserve equal attention. A 1:1 CBD: THC ratio containing mostly beta-caryophyllene and limonene will have markedly different effects from a product with the same 1:1 CBD: THC ratio but containing terpenes like linalool, humulene, and myrcene.

    How Do the Effects of Different CBD:THC Ratios Vary?

    Equal CBD: THC ratios may produce limited psychoactive effects. People often want some psychoactive effect for therapeutic reasons, as THC can help users mentally overcome the pain. High-CBD, low-THC strains produce few if any psychoactive effects for most people, although some may still be felt. CBD still imparts an effect even if it is not psychoactive in THC’s sense.

    Low-THC, high-CBD strains are seen as particularly useful for children or those sensitive to THC, as they are not less intoxicating and still contain enough THC for therapeutic use. However, this is not always the case: many people may be doing themselves a disservice by opting for high-CBD alone, especially if they have a specific condition where higher (though not necessarily psychoactive) amounts of THC may be needed.

    A Quick Note on the “Psychoactivity” of Cannabis

    Depending upon the strain and cannabinoids it contains, most people who use medical marijuana report feeling euphoric, relaxed, giggly, chatty, sleepy, happy, and so on. These effects are one reason why many people enjoy cannabis, particularly when the dosage is right and allows them to remain functional . Users tend not to see pink elephants and wizards casting magic spells when using cannabis, unless they consume an extremely strong, high-THC edible and have not built tolerance to high doses of cannabis. And even then, you are more likely to fall asleep than see pink elephants.

    This raises another issue about cannabis’s psychoactive constituents. After all, if CBD is having a physiological effect, helping you feel sleepy and relaxed or giving you a “jolt” of energy and focus, could it not be said that CBD is psychoactive? Sure, you won’t get the euphoric effects usually associated with THC, but to say that CBD has no physiological and psychoactive effect whatsoever is simplistic (and plain wrong – CBD definitely does have physiological effects). You can read more on how CBD works here.

    michigan marijuana


    Though the 1:1 CBD: THC ratio is popular, it is not the end all be all to cannabis as a medicine. The 1:1 ratio provides a starting point for many, though, and will help consumers think of cannabis in terms of genetics, cannabinoids, and terpenoids rather than strain names. At the moment, consumers rely upon an unstandardized system of understanding cannabis experiences based on strain names. It’s simply not enough to know the strain name. The growing environment and generation of a particular strain may yield very different cannabinoid-terpenoid-flavonoid profiles, making it tricky to claim a particular strain is better suited than another for a particular condition.

    Download Our 1 Pager Guide to Dosing Medical Marijuana

    Want to know what kind of medical marijuana might help your condition? Check out our conditions page and apply for your MMJ card online today!



Written by
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Shanti Ryle

Shanti Ryle is a content marketer with more than half a decades’ experience writing about cannabis science and culture. Her work has been featured in Forbes, Weedmaps News/Marijuana.com, Wall Street Journal, and other publications.

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