Eight years later, a 2019 test compared the efficacy of three CBD doses (150 milligrams, 300 milligrams and 600 milligrams) and a placebo in men taking an SPST  Linares IM, Zuardi AW, Pereira LC, et al. Cannabidiol presents an inverted U-shaped dose-response curve in a simulated public speaking test. Revista brasileira de psiquiatria (Sao Paulo, Brazil : 1999). 2019;41(1):9-14. . Compared to a placebo, 300 milligrams of CBD significantly reduced participants’ anxiety during the speech, but the 150-milligram and 600-milligram doses did not. These results highlight how dosage can be highly variable and that more CBD isn’t necessarily more effective.
Here’s what the science says regarding CBD’s anxiolytic properties, along with experts’ dosage guidelines and advice on how to take CBD safely.
CBD for Generalized Anxiety
Another study involving hundreds of patients noted success with doses from 40 milligrams to 300 milligrams a day, further supporting the idea that CBD dosage varies significantly, depending on a person’s symptoms and physiology.
Other studies suggest CBD can reduce PTSD symptoms when consumed with THC  Bitencourt RM, Takahashi RN. Cannabidiol as a Therapeutic Alternative for Post-traumatic Stress Disorder: From Bench Research to Confirmation in Human Trials. Front Neurosci. 2018;12:502. . When taken together, the two compounds create what’s known as the “entourage effect,” where THC enhances the effects of CBD as CBD tempers the effects of THC, resulting in a more well-rounded experience  Ferber SG, Namdar D, Hen-Shoval D, et al. The “Entourage Effect”. Terpenes Coupled with Cannabinoids for the Treatment of Mood Disorders and Anxiety Disorders. Curr Neuropharmacol. 2020;18(2):87-96. .
CBD for Anxiety
However, other trials suggest much lower doses are also quite effective in treating anxiety.
Researchers gave different dosages of CBD to participants before a public speaking test. They found that subjective anxiety measures dropped with a 300 mg dose of CBD. This drop did not occur with either the 100 or 900 mg CBD dosages.
So far, most of the evidence linked to CBD’s effects on anxiety comes from animal studies and laboratory experiments. But it does show some promise.
CBD does not appear to ease paranoia, however. A study published in the Journal of Psychopharmacology tested the effects of CBD in people with high paranoid traits.
Anxiety in Healthy Participants Study
This article will explain why people take CBD oil and some of the side effects they could expect. It also provides an update about some of the fascinating research that has been done on the subject so far.
The uncertainty explains why it makes good sense to consult your healthcare provider before taking CBD oil. If your physician cannot recommend a brand, then he or she may be able to warn you off an irreputable brand.
Researchers concluded this after testing participants' responses to negative images or words and threatening faces after they took oral CBD.
Left untreated, an anxiety disorder can diminish your quality of life. It can also lead to health issues, such as digestive problems.
Dr. Yasmin Hurd: Ironically, even though it’s now this huge fad in our society, we still don’t have a very good handle on how it’s working.
Steven Phan: You gotta lean back. No, tongue back!
Dr. Hurd: “How do you feel?”
So, I happened to take CBD right before I had to do something stressful. It’s Sunday, but I had a task that I was not looking forward to. And I took 100 milligrams, and I pretty quickly felt my nerves calming down. And I was like, OMG, this is totally working, which is really great because I’m looking for that quick relief like everyone is.
Dr. Hurd: “It can activate some serotonin receptors, and the serotonin system is associated with alleviating anxiety.”
At that point, I had just one day left.
CBD is a distant cousin of THC, the psychoactive chemical in marijuana. They both come from the cannabis plant, but CBD isn’t psychoactive. Meaning it doesn’t get you high. Now, of course, getting high isn’t the only reason why cannabis is popular. People also use it to relieve pain, control seizures, and lessen anxiety. But as researchers like Dr. Yasmin Hurd are discovering, it’s likely CBD, not THC, that’s behind these benefits.
Dr. Hurd: “Both under normal conditions and in people who have anxiety disorders, enough research has started to show that it does have an anti-anxiety effect.”
Jones: In other words, we don’t know: what size dose you should take, how, exactly, it changes your brain, or how it impacts different people in different ways. That’s because until late 2018, nearly all CBD was classified as an illegal substance. Which made it really difficult for scientists to study. And while research is starting to catch up… in some ways, it’s too late.