In this article, we simplify and summarise the evidence for using a different CBD:THC Ratio for the treatment of a variety of indications What do CBD to THC ratios mean and what can they really do? Selecting quality cannabis products takes some time and careful consideration. Knowing what is in the products you choose is important.
CBD:THC ratio explained
The use of cannabis for medicinal purposes is becoming more and more accepted throughout many countries. With the increased use of these medicines, the CBD:THC ratio is becoming more important. As popularity grows, research is being done to further understand the therapeutic benefits of different combination formulations and doses.
Currently, in New Zealand, only one medicinal cannabis product (Sativex) has been approved by Medsafe. This is for use as an add-on treatment for the symptoms of moderate to severe spasticity due to multiple sclerosis (MS). Sativex contains equal amounts of CBD and THC (a 1:1 ratio).
However, a broader range of CBD:THC combinations are being investigated to treat other indications, such as pain, epilepsy, anxiety, sleep disorders, etc. These combinations range from CBD-dominant to THC-dominant, for example, CBD:THC 20:1 through to CBD:THC 1:10.
Understanding which combination to use on individual patients is challenging. The following sections provide guidance to help understand how the ratio of CBD:THC works so that going forward you can improve the effectiveness of medicinal cannabis.
Understanding CBD and THC
Cannabidiol (CBD) and tetrahydrocannabinol (THC) are both natural compounds found in plants of the Cannabis genus. Although both compounds interact with the body’s endocannabinoid system, the effects of these two compounds are very different. THC binds to CB1 receptors in the brain and causes feelings of euphoria or ‘a high’. CBD binds weakly to the CB1 receptor and only when THC is present. CBD does not produce euphoria or ‘a high’.
CBD and THC can be combined in medicinal products in different ratios to produce different therapeutic effects. Because the use of medical cannabis is a relatively new area in medicine, there is still a lot of research to be done in this area. We are still learning what ratios are best for managing various conditions.
What is a CBD:THC ratio?
The ratio of CBD to THC indicates the amount of CBD compared to the amount of THC in a dose. For example, a ratio of 1:1 would mean that the amount of CBD and THC are the same in each dose. A CBD:THC ratio of 20:1 would mean that there is 20 times the amount of CBD in a dose compared to THC. Changing the ratio of CBD to THC allows for a tailor-made product that utilises the unique effects of either CBD, THC, or both for a particular patient or clinical effect.
What are the most common ratios?
Cannabis cultivars grown for the recreational market have seen a steady increase in THC content, paired with a decrease in CBD. Smoking these varieties will give the user a more potent ‘high’, but this might come at the cost of some therapeutic effects.
Medical use of CBD and THC has changed that, allowing specific ratios of CBD:THC to be selected to provide the greatest clinical benefit for each patient. Now, most medicinal cannabis products are higher in CBD than THC. Pure CBD products are considered to have less than 0.3% THC. The trend has moved towards cultivating plants or producing products that have a higher CBD to THC ratio. Ratios of CBD:THC can range between >20:1 all the way to 1:10. As a general rule of thumb, anything higher than a CBD:THC ratio of 10:1 should not elicit a high.
CBD:THC ratio for pain
By changing the ratio of CBD to THC, you are able to target and manage different types of pain.
Mild to moderate pain due to inflammation (think arthritis-type pain) can be managed well with CBD-dominant products such as CBD:THC 20:1 and 10:1. These ratios will be unlikely to induce any intoxicating effects.
Neuropathic pain, from disease or damage to the nervous system, might be better treated by increasing the ratio of THC towards a balanced ratio, 1:1. The exact ratio will depend on the severity of the condition and how well THC can be tolerated by the patient.
Very severe pain, such as cancer pain, may require THC-dominant medications. It is important to understand that THC-dominant products may induce euphoria and sedation, so care needs to be taken.
CBD:THC ratio for anxiety
Smoking cannabis can induce paranoia or extreme anxiety in certain people, so it seems counterintuitive that you could use medical cannabis preparations for the management of anxiety.
CBD has demonstrated efficacy in treating various forms of anxiety and is commonly used for this purpose. However, recreational use of high-THC cannabis is associated with increased anxiety, particularly in high doses. Reports suggest that THC has a dose-dependent effect on anxiety, where at low doses THC may be anxiolytic (reduce anxiety) but at higher doses can be anxiogenic (cause anxiety). Therefore, CBD-dominant products (CBD:THC >10:1) are likely to provide the most beneficial treatment, and in some cases, pure CBD with no THC present may be the best product to treat anxiety.
CBD:THC ratio for insomnia
Insomnia is a widespread problem and has been linked to illnesses ranging from depression to cardiovascular disease to dementia. Many allopathic medications used in the management of insomnia have adverse side effects, such as daytime drowsiness or addiction.
THC is well-known to have sedating properties via its action at the CB1 receptor; however, its use alone can cause increased anxiety and lead to other undesirable effects. By adjusting the ratio of CBD:THC, it is possible to block these undesirable effects while still retaining sedating properties. A current study is looking at a CBD:THC ratio of 20:1 in the treatment of chronic insomnia. If you are taking medicinal cannabis for other indications, it may be possible to investigate adding a slightly higher dose of THC at night-time to maximise the sedating effects and reverting to the lower THC ratio for daytime use.
How to pick the best CBD:THC ratio for your patient
This infographic provides ratios of CBD:THC and considerations of which ratio to use for certain conditions.
Currently, the only available medical cannabis in New Zealand contains a ratio of CBD:THC at 1:1; however, going forward you will be able to prescribe your patient other preparations of CBD:THC at a ratio that is optimal for what they want to achieve. The following is a rough guide of what to expect from different ratios:
CBD:THC at a ratio of 1:2
This preparation contains twice as much THC as CBD and will have intoxicating effects, especially for new or naive users. The presence of some CBD in the preparation will dampen some side effects of the higher THC, such as paranoia, but not all. This ratio would be better suited for people who have been using medical cannabis on a chronic basis, e.g., for intractable nausea, poor appetite, or glaucoma, and have developed a high degree of tolerance.
CBD:THC at a ratio of 1:1
This preparation contains equal amounts of CBD and THC and, depending on the dose, is likely to cause symptoms of euphoria or intoxication, especially in people who are naive to cannabis use. If using this ratio, it would be prudent to start with low doses and increase slowly according to tolerance.
CBD:THC at a ratio of between 2:1 and 4:1
Preparations with this ratio of CBD to THC can be psychoactive, especially to people who have poor tolerance for THC. The increased CBD does have beneficial effects and causes some dampening of the effects of THC.
CBD:THC at a ratio of more than 10:1
CBD:THC ratios >10:1 generally produce no intoxicating effects and are ideal for patients that are not able to take THC during the day (e.g., due to driving or work). Where the condition to be treated does not require THC, these products may help provide relief for certain conditions without any intoxication of the patient. This is a really safe dose for those people who want to experience the beneficial effects of CBD without the psychoactive effects of THC.
The bottom line
There is definitely an advantage to being able to adjust the ratio of CBD:THC in your medical cannabis preparation. This will allow you to maximise the particular benefits that you want while minimising any unwanted negative side effects. Currently, the standard preparation contains a fixed ratio of CBD:THC; however, going forward new research may strengthen the argument for flexible dosing.
THC is psychoactive and may impair your ability to undertake certain tasks, such as driving or operating machinery. CBD is non-psychoactive and non-sedating and can be safely used at much higher doses than THC.
With all medicinal cannabis, it is important to start with a low dose and gradually increase it over a few days. This is particularly important for compositions containing THC. Remember: START LOW and GO SLOW.
Understanding the confusing world of CBD and THC ratios
This post is part of our High-tech High series, which explores weed innovations, and our cultural relationship with cannabis, as legalization in several U.S. states, Canada, and Uruguay moves the market further out of the shadows.
There’s a flurry of new numbers on marijuana product labels, and the ratios can feel like a confusing math problem.
But there’s a method to the madness — one based more on anecdotes than broadly recognized scientific research.
A variety of vape oils, tinctures, salves, and edibles with numbers like 18:1, 4:1, and 1:1 — noting the amount of CBD to THC — have been showing up at dispensaries in recent years in both medical and recreational states. THC will make you high, while its sister compound CBD generally won’t — and has therapeutic potential. Most marijuana strains have around 18 percent THC with less than 1 percent CBD (with THC sometimes being pushed beyond 20 percent).
The cannabis companies behind the trend aren’t chucking THC; they’re just flipping the ratios. For decades, growers have focused on breeding weed with increased amounts of THC. That’s still the case to a large degree, but a sliver of the market sees big things for CBD-rich marijuana products.
“They kept getting bred to go higher and higher in THC, so most strains have very low CBD,” said Dennis Hunter, cofounder of Cannacraft, a Santa Rosa cannabis producer with a line of CBD-rich products under the brand name Care by Design. “Now they’re starting to breed those to be higher and higher in CBD.”
Care by Design, and other companies like Pure Ratios in San Diego, use previous customers’ experiences to guide new users toward their preferred ratio.
But with scant evidence-backed scientific research regarding the impact of each ratio, consumers resort to trial and error to see what works for them.
CBD-rich products are marketed toward those seeking relief from anxiety, arthritis, seizures, stress, inflammation, and overall wellness, not necessarily a high. They’re also being used to ease those once spooked off by a bad marijuana experience back in. Baby boomers are Care by Design’s biggest growing customer base.
There are plenty of anecdotes from customers reporting life-changing relief with unregulated CBD-rich products, but it’s still a gamble and you’re the guinea pig. And these products aren’t cheap. Care by Design’s cartridges are $50 and its droppers are $40. Pure Ratios’ droppers are around $30. CBD oil made from hemp, which has less than 0.3 percent THC, from Bloom Farms, for example, ranges from $60 to $90.
Cinnamon Bidwell, a neurobiologist at the University of Colorado Boulder’s Institute of Cognitive Science, cautions not to get swept up in the testimonials promoted by cannabis manufacturers.
“The marketing and the consumer lure is far ahead of what the research can really support,” said Bidwell. That seems to be the case for marijuana in general since its classification as a so-called Schedule 1 drug — which means the federal government believes it has “no currently accepted medical use and a high potential for abuse” — makes it difficult to study. Bidwell’s lab, which is in a state that has legalized recreational marijuana, is conducting a 5-year study comparing the cannabinoids subjects ingest to what shows up in their bloodstreams in relation to clinical outcomes.
What’s more, all the ratios can be hard to understand. Care by Design offers five (18:1, 8:1, 4:1, 2:1, and 1:1), while Pure Ratios cut down to three (18:1, 4:1, and 1:1) because customers were confused by the variety, said CEO Chad Conner.
Here’s a rule of thumb: The higher the CBD, the less of a high you’ll get from the THC, both because there’s less of it and CBD generally combats THC’s psychoactive effects, depending on the amount of THC you’ve consumed, according to cannabis researchers and producers.
When you’re deciding which ratio is right for you, it’ll take some experimenting. Both Hunter and Conner suggest starting with a high-level of CBD and working your way down to a more balanced product. You’ll have to play around with the amount, too, but take it slow.
Care by Design sells a sampler pack to help in the guessing game. The ends of the spectrum, 18:1 or 1:1, are its best sellers; either consumers don’t want to feel psychoactive effects or they do, it seems.
The trial and error, Bidwell said, is what happens when cannabis products rush into the market before there’s sufficient research.
There is, however, a prescription 1:1 CBD to THC mouth spray called Sativex made in the UK and available in several countries including Spain, Germany, Canada, and Brazil that’s meant to treat spasms in MS patients. It’s undergoing clinical trials in the U.S. Epidiolex, the first FDA-approved cannabis-derived drug in the states, is high in CBD with trace amounts of THC (not enough to have any pharmacological effect). It’s used to treat seizures.
“We’re starting to understand what CBD does, but even that is very minimal. And in terms of these different ratios, there’s an idea or a hypothesis that there’s something there in terms of THC facilitating CBD’s action in a different way, if not more in different amounts. But in terms of the science being able to contribute to that in any kind of clear way, we’re not there yet,” Bidwell said.
Elliot Altman, biology director of the Tennessee Center for Botanical Medicine Research, disagrees with that assessment when it comes to CBD’s therapeutic benefits. His lab at Middle Tennessee State University studies CBD and hemp. Marijuana isn’t legal in Tennessee, but hemp is. Most CBD products are made from hemp extract, while the ratio products tend to include a variety of cannabis strains to get the right proportion.
It’s clear to Altman, who does not study THC, that CBD provides relief for those with inflammatory or autoimmune conditions, but if you’re looking for pain relief, that’s going to come from THC. Altman’s lab works with private groups looking to sell CBD from hemp as a nutritional supplement.
“THC is for pain, and CBD is for when your immune system is compromised,” Altman said. His take on these emerging products is pretty simple: “If what you’re really after is CBD, but you’re in a marijuana state, take a little THC to take the edge off, don’t take excessive THC.”
The National Academies of Sciences, Engineering, and Medicine put out a 2017 report surveying the scientific research done so far on the health impacts of cannabis. There is conclusive or substantial evidence that cannabis is effective in treating cancer patients with nausea, adults with chronic pain, and MS patients with spasms, according to the report. But, there’s limited evidence that CBD can lessen anxiety and “no accepted standards exist to help guide individuals as they make choices regarding if, when, where, and how to use cannabis safely and, in regard to therapeutic uses, effectively.”
In addition to CBD:THC ratios, the U.S. cannabis community sees a bright future for hemp-only products. The 2018 Farm Bill, which passed Wednesday, will legalize industrial hemp on the federal level once signed by the president. There are many hemp products already being sold promising calm and pain relief.
“The CBD hemp business is gonna grow way bigger. Then marijuana will take over when it’s federally legal,” Conner, of Pure Ratios, predicted.
And the future may have even more numbers in store.
Cannabis sellers forecast other lesser-known cannabis compounds like THCV, a possible appetite suppressant, may one day be included in ratios on packaging.
Hunter also sees powder packs of these products coming up the line — imagine Emergen-C, but with CBD. Care by Design’s working on it. Coca Cola is also exploring the CBD beverage market.
“Seems like every day or week we keep finding out more and more interesting information,” Hunter said.
Understanding CBD:THC Ratios
Selecting quality cannabis products takes some time and careful consideration. Knowing what is in the products you choose is important. Knowing how much of each of those ingredients or components is in a product – not just the amount but also the ratio of one key ingredient to another – is also key to anticipating the potential effects that product may produce.
When we’re talking about cannabis products, the term “ratio” typically refers to the ratio of CBD to THC. These types of ratios can be expressed as CBD:THC (the amount of CBD versus THC).
As we discussed in “The Entourage or Ensemble Effect”, the relationship between THC and CBD is interesting because it is both complementary and antagonistic meaning they both work together in some ways, but in other ways, they work to modify the effects of the other.
Here are some examples of ratios and what those ratios could mean:
40:1 – 40 parts CBD to 1 part THC. This ratio contains a significantly higher amount of CBD that will impact the way the low amount of THC works overall. The focus of a product with this combination is on the benefits of CBD.
18:1 – 18 parts CBD to 1 part THC. With a higher CBD content compared to the THC content, this ratio is not overly psychoactive and can be a good starting point for someone new to CBD or THC.
8:1 – 8 parts CBD to 1 part THC which is more of a mid-range amount of CBD. Again, the CBD content dominates the THC content for a tempering effect that minimizes overt psychoactivity.
4:1 – 4 parts CBD to 1 part THC. This ratio still has a CBD content higher than the THC, which is in the mid-range, but the THC will produce some more pronounced psychoactive effects.
2:1 – 2 parts CBD to 1 part THC. There could be more overt psychoactivity depending on a person’s THC tolerance level since this ratio is a little more equal, with less CBD to temper the THC.
1:1 – 1 part CBD to 1 part THC. While this ratio looks the most balanced, it will actually produce more of an overall psychoactivity and may be better suited for a person with a higher tolerance to THC.
Picking the right ratio is an individual thing – no two people’s bodies or brains (or endocannabinoid systems) are alike. If a person is a novice, a reasonable place to start is at the ratio with the highest amount of CBD versus the THC content. Over time, easing into trying ratios with higher THC will, inevitably, produce different effects but how strong is to be determined person to person.