This website has been created with one purpose in mind. The reality behind cannabidiol’s medical hype by looking closely at the current scientific research. The cannabis compound known as CBD is being touted as a treatment for a variety of conditions, but is this really the case? What does science say?
We will try to summarize the current scientific evidence in layman terms, so the average person who is swimming in a sea of misinformation can make informed decisions about the usefulness of CBD. And people who write about CBD online can link to a resource which is impartial and where information is summarized clear, easy to read and easy to understand.
We will start by looking at what the most reputable sources like WHO, CDC have to say. We will look at all the research and point out where studies fall short, if they have conflicting interests and if they are peer reviewed or published in reputable scientific journals.
First, what is CBD?
Cannabidiol (CBD) is one of the naturally occurring cannabinoids found in cannabis plants. Unlike tetrahydrocannabinol (THC), another type of cannabinoid, CBD doesn’t cause any feelings of intoxication or the “high” you may associate with cannabis.
Is there scientific evidence for CBD benefits?
Yes, there is. But certainly not for everything that is claimed on the Internet. The most important guidelines we have at date come from WHO. According to this report from the WHO, CBD has been demonstrated as an effective treatment of epilepsy in several clinical trials, with one pure CBD product (Epidiolex®) currently in Phase III trials. The WHO also states that there is also preliminary evidence that CBD may be a useful treatment for a number of other medical conditions. CBD is generally well tolerated with a good safety profile.
Is CBD good for epilepsy?
Yes. According to the WHO report published at the end of 2017, the clinical use of CBD is most advanced in the treatment of epilepsy. In clinical trials, CBD has been demonstrated as an effective treatment for at least some forms of epilepsy, with one pure CBD product (Epidiolex®) currently in Phase III trials. There are 5 studies covered in the WHO report that showed significant effects (1 to 5 covered below), and two which showed no effectiveness (6 to 7, even though one was for a longer term period, but still had a small sample size).
- The first study was a very early small-scale double-blind placebo controlled trial done in 1977 in which patients received either 200 mg CBD daily (4 patients) or placebo (5 patients) for a 3-month period, in addition to their habitual medication. In the CBD group, two patients had no seizures for the entire 3-month period, one partially improved, and the fourth had no improvement. No improvements were observed in the placebo group and no toxic effects were reported for either group. This study has a number of limitations, including the small sample size, unclear design as to blinding, and lack of definition of partial improvement.
- The second study done in 1980 followed 15 patients with “secondarily generalized epilepsy with temporal focus,” were randomly divided into two groups. In a double-blind procedure, each patient received 200-300 mg daily of CBD or placebo for up to four and a half months in combination with their existing prescribed antiepileptic medications (which were no longer effective in the control of their symptoms). Of the eight participants in the CBD treatment group, four were reported to be almost free of seizure episodes throughout the trial. CBD was ineffective in one patient. In comparison, the clinical condition of seven placebo patients remained unchanged with one patient showing improvement.
- The third study done in 2016 examined CBD effects in patients with severe, intractable, childhood-onset, treatment-resistant epilepsy. This analyzed 214 patients (aged 1–30 years) who were receiving stable doses of antiepileptic drugs before study entry. Patients were given oral cannabidiol, initially at 2–5 mg/kg per day. The primary measure was the percentage change in the frequency of seizures. This study concluded that cannabidiol might reduce seizure frequency and might have an adequate safety profile in children and young adults
- The 4th study was done by the same research group in 2017, and reported the results of a controlled trial of CBD treatment for Dravet syndrome, a complex childhood epilepsy disorder that is associated with drug-resistant seizures and a high mortality rate.This was a double-blind, placebo-controlled trial, 120 children and young adults with Dravet syndrome were randomly assigned to receive either cannabidiol oral solution (20 mg per kilogram per day) or placebo, in addition to standard antiepileptic treatment . The authors reported that cannabidiol decreased the median frequency of convulsive seizures per month from 12.4 to 5.9, as compared with a decrease from 14.9 to 14.1 with placebo. And in addition a small percentage (5%) of patients in the CBD group became seizure free as compared to zero in the placebo group.
- The 5th study covered in the WHO report was done in 1986, a dose of CBD of 200–300 mg/day for a month resulted in no significant differences between the treatment and placebo groups.
- The 6th study covered in the WHO report, done in 1990 was designed to evaluate the anticonvulsant activity of cannabidiol (CBD) in a group of twelve adult in a double-blind, cross-over, placebo-controlled, add-on study lasting two years. The project tried to evaluate the effects of chronic CBD administration upon seizure frequency and character. The study concluded no changes in seizure frequency or improvement in cognition or behaviour.
Is there any abuse potential?
The same report from Who states that based on current evidente from well controlled human experimental research indicates that CBD is not associated with abuse potential. But we have to take into account that the number of existing studies is limited. They point out to this study in which Oral THC 10 mg or CBD 600 mg or placebo was administered to 16 healthy male subjects in three consecutive sessions, at one-month interval. In this study CBD has proven to be safe and well tolerated, while THC had marked acute behavioural and physiological effects. The important things about this study are that it was a randomised, double-blind, cross-over, placebo controlled trial, and that it was done on only 16 individuals.
Labeling accuracy of CBD extracts sold online
One important thing you should know before buying CBD products is related to the accuracy of labeling. About 1 in 3 CBD products readily available to US consumers contained less CBD than labeled (which could negate any potential clinical response). If you made up your mind, than this should be the first thing you check and get well informed on. The labeling accuracy surfaced in this study made in 2016 (things might have change since). Researchers looked for CBD products sold online for a month and purchased anything readily available (excluding products with similar formulation). They acquired 84 products from 31 companies. Within 2 weeks of receipt, product labels were replaced with blinded study identifiers and sent to the laboratories at Botanacor Services for analysis of cannabinoid content. 26% contained less CBD than labeled. There were other labeling issues, you can check them here.
Noteworthy things about this study are:
- it was done quite a long time ago -> 2016, since then things might have changed to the better or worse. Nowadays there are way more products on the market.
- some of the researchers received personal fees from companies that manufacture CBD products. Things might be even worse than stated, we need more research to confirm these findings
Once you’ve made a decision about the type of product you’re looking for, you’ll want to check the ingredient label of the product in question. A reputable CBD product will come with a COA (Certificate Of Analysis). This is is a a document issued by an accredited laboratory (that doesn’t have a stake in the product) that includes a full composition of a product. By checking this document you can confirm that it contains what it said it does, and even with an extra bonus: it should include possible contaminants such as pesticides, solvent residue or heavy metals. However, the COAs aren’t always easy to get to your hands on. You may need to reach out to the company from which you want to buy. However, it’s worth the trouble, and you can easily filter companies which act shady, and don’t stand for quality and transparency.