Frequently asked questions

The cannabis oil that is typically available in dispensaries is THC-dominant with little cannabidiol. To extract CBD-rich cannabis oil, one must start with CBD-rich plant material. There many ways to extract oil from the cannabis plant, each has its pros and cons. Some methods are safer and more effective than others. Cannabis oils made with neurotoxic solvents like butane and hexane may leave unsafe residues that interfere with immune function and impede healing. Super-critical CO2 extraction, while non-toxic, requires significant expertise and access to expensive equipment. Home-brewers can also use safer solvents, such as ethanol, or prevent exposure to organic solvents entirely by using olive oil to extract cannabis oil, according to Dr. Arno Hazekamp director of phytochemical research at Bedrocan BV, which supplies cannabis, including a CBD-rich strain, for the Dutch Health Ministry’s medical marijuana program. Hazekamp coauthored this report on cannabis oil extraction methods.
By juicing or otherwise ingesting raw, unheated cannabis, one consumes THC and the other cannabinoids in their acid form. A CBD-rich strain contains CBD-acid, which, when heated, becomes CBD. Unheated CBD-acid and unheated THC-acid both have medicinal attributes, but there has been comparatively little scientific research into cannabinoid acids.
A CBD-dominant strain or product with little THC is not necessarily a superior treatment option compared to a balanced CBD-rich remedy with an equal amount of CBD and THC. A CBD-dominant extract or strain might be optimal for treating anxiety and seizure disorders, whereas most pain syndromes and neurodegenerative disorders may benefit from a substantial amount of THC. CBD and THC act synergistically to potentiate their respective therapeutic attributes. Different ratios of CBD and THC are more suitable for different conditions and different individuals.
Drug tests are geared toward identifying THC, not CBD or another cannabinoid. If one medicates with CBD-rich cannabis that has only a small amount of THC, the THC may register on a drug test. A drug test geared toward CBD would not be an effective law enforcement tool, given that CBD is not psychoactive and does not cause impairment.
CBD is metabolized into an analogous compound, 7-hydroxy-CBD. There may also be some 6-OH-CBD. But scientists know relatively little about the activity (or lack thereof) of these compounds.

If you live in one of the 22 countries that have approved GW’s Sativex, a fifty/fifty CBD/THC whole plant under-the-tongue spray, you may qualify for a prescription. CBD-derived from industrial hemp grown in Europe is legal and available in the European Union. The Dutch Health Ministry distributes a CBD-rich cannabis strain to patients enrolled in the Netherland’s official medical marijuana program. The official Israeli medical marijuana program also grows and dispenses CBD-rich strains. Those who live outside the USA can also visit—or coordinate with a friend or relative in—Colorado or Washington, where cannabis is legal and available for personal use for those 21 years or older. How one elects to travel with or transport their medication, which is prohibited by federal law, is their own responsibility. High quality CBD-rich products are also available in California. In order to be in receipt of any California cannabis product one must be in possession of a valid medical cannabis recommendation letter from a California physician. Some patients and/or caregivers come to California and establish a temporary California residence to obtain a California ID. With this ID, they can see a California medical cannabis expert, get a letter of recommendation, and then obtain CBD-rich medicine. A number of patients and their families have relocated to cannabis-friendly states in order to access CBD-rich medicine on a consistent basis.

To access CBD-rich medicine, one may need to visit—or coordinate with a friend or relative in—Colorado or Washington, where cannabis is legal and available for personal use for those 21 years or older. How one elects to travel with or transport their medication, which is prohibited by federal law, is their own responsibility. High quality CBD-rich products are also readily available in California. In order to be in receipt of any California cannabis product one must be in possession of a valid medical cannabis recommendation letter from a California physician. Some patients and/or caregivers come to California and establish a temporary California residence to obtain a California ID. With this ID, they can see a California medical cannabis expert, get a letter of recommendation, and then obtain CBD-rich medicine. A number of patients and their families have relocated to cannabis-friendly states in order to access CBD-rich medicine on a consistent basis.

Project CBD was launched in 2010 by two journalists, Fred Gardner and Martin A. Lee. Lee is the director of Project CBD and the author of several books, including, most recently, Smoke Signals: A Social History of MarijuanaMedical, Recreational and Scientific (Scribner 2012). Lee is also the author of Acid Dreams and a cofounder of the media watch group FAIR. Project CBD cofounder Fred Gardner was on the editorial board of Scientific American in the 1960s. He has been managing editor of Synapse, the UC San Francisco weekly, and public information officer for the District Attorney of San Francisco. Since 2003 he has edited O’Shaughnessy’s, the journal of cannabis in clinical practice.

Although cannabidiol has been studied since its molecular structure was elucidated in the mid-1960s and there have been numerous CBD lab studies (using mice as test subjects), only a few clinical studies (using people as test subjects in a controlled setting) have been conducted. While these studies strongly suggest that CBD will benefit people, more real-life investigation is called for. We trust ourselves and the doctors we’re working with to do an honest job. We don’t pretend we’re not biased—we’re hoping that CBD-rich cannabis proves helpful to people in various ways. We trust ourselves, nevertheless, to report the facts as we learn them—period.

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By the same methods one would use to make any kind of cannabis-infused edible. To make a CBD-rich brownie or another CBD-rich edible, one must first extract oil from a CBD-rich strain and infuse it into olive or coconut oil or butter or ghee (clarified butter). These infused oils or butters are the most common ways to cook with cannabis. One will need to combine the CBD-rich plant material (usually the leafy trim) with the oil or butter and expose to low heat over a long period of time – this will help to avoid breakdown and/or vaporization of the CBD and other cannabinoids. After straining out the plant material, one can substitute CBD-rich cannabutter or canna-oil into your favorite recipes. There are many extraction recipes and tutorials available on-line, including, for example, Le Blanc Cne.

We recommend CBD-rich products made using only organic, whole plant cannabis because this offers the best safety profile and superior medicinal benefits. CBD products derived from industrial hemp potentially have several potential problems: Industrial hemp typically contains far less cannabidiol than CBD-rich cannabis strains, so a huge amount of industrial hemp is required to extract a small amount of CBD. This raises the risk of contaminants as hemp is a “bio-accumulator,” meaning the plant naturally drawns toxins from the soil. Hemp-derived CBD and refined ‘pure’ CBD powder lack critical medicinal terpenes and secondary cannabinoids found in cannabis oil. These compounds interact with CBD and THC to enhance their medicinal benefits.
It is true that hemp fiber or seed strains will be relatively high in CBD (compared to THC), but the overall cannabinoid content of industrial hemp will probably be low. Industrial Hemp is genetically bred to produce fiber for various products or seed for omega oil and nutritional supplements. Industrial hemp is generally not bred for resin production. CBD-rich yields from hemp are likely to be low without selective breeding for CBD content.
Contrary to some rumors, a plant cannot be made CBD-rich if it lacks the right genetic make-up. The ratio of THC, CBD, and other cannabinoids is genetically determined, according to a study by biochemist Etienne de Meijer, “Inheritance of the Cannabinoid Phenotype.” A grower can, however, influence overall cannabinoid content by manipulating environmental factors – temperature, light, water acidity, and nutrients – that affect plant health.
The same growing techniques apply to CBD-rich cannabis and high-THC cannabis. Much like growing high-THC strains, harvesting earlier or later can impact the cannabinoid levels as well as the terpenoid profile of the plant. For somewhat higher CBD content, try harvesting CBD plants a couple weeks earlier than one would typically harvest a high THC strain.

We do not. Project CBD is an educational news service. We review and report on  CBD-rich products, but we don’t sell them. Seed companies, clone-providers, product-makers, and dispensaries affiliated with Project CBD are listed here.

Depending on where you live, we may be able to suggest medical marijuana dispensaries in your area that carry CBD-rich medicine. The Project CBD website includes a list of affiliated dispensaries that are committed to providing CBD-rich medicine in states that have legalized medical marijuana. CBD oil extracted from industrial hemp is also available through online storefronts and a handful of actual storefronts in states that have legalized CBD (but not the whole plant). The quality of hemp-derived CBD products is inconsistent but sometimes patients find these to be effective.

Yes. CBD inhibits the cytochrome P450 enzyme, which is involved in metabolizing many drugs. Compounds in grapefruit inhibit the same enzyme group, which is why physicians advice patients not to eat grapefruit shortly before or after taking a medication. By inhibiting cytochrome P450, CBD can either reduce or increase the effects of other drugs. In some situations, it may be advisable for a physician to monitor a patient’s blood levels of other medications while taking CBD. See CBD-Drug Interactions: The Role of Cytochrome P450 for more information.

Project CBD has published a Cannabis Dosing Guide for patients and health professionals.

By “CBD-rich,” we mean a cannabis strain or product that has equal amounts of CBD and THC, or more CBD than THC (usually at least 4 percent CBD by dry weight.). By “CBD-dominant,” we mean strains or products that are CBD-rich but have very little THC content.

Technically, CBD is forbidden in any form (pure or from a plant) in the USA, despite its total lack of addictive potential or any rational danger. Cannabidiol and all other plant cannabinoids are Schedule I drugs in the USA. The code number for cannabidiol in Schedule I is 7372. CBD is not psychoactive, but it is illegal in the eyes of the federal government. You may find it listed here: under Schedule I where it says tetrahydrocannabinols. The part saying “and others” includes all phytocannabinoids, even CBD. However there are exceptions. American scientists with a DEA license in some cases are permitted to experiment with pure synthetic CBD. Some online businesses falsely claim that CBD oil derived from industrial hemp grown abroad is legal in all 50 U.S. states, as long as the THC content of this oil is less than .3 percent (in accordance with federal rules regarding industrial hemp products). Currently, it’s against federal law to use hemp leaves and flowers to make drug products. Hemp oil entrepreneurs attempt to sidestep this legal hurdle by claiming they extract CBD only from hemp stalk before importing it to the United States, a grey area activity at best. Although the FDA has issued warning letters against some CBD hemp oil companies for making false claims about their products, thus far the federal government has not take action to halt these illegal business operations. The situation is different in Europe, where CBD is not a controlled substance.

For further information on the CBD legality issue: