Meanwhile, at least one study in mice revealed CBD had effects similar to the antidepressant imipramine. Human trials are needed, though, to confirm whether CBD can induce this same antidepressant reaction in our bodies.
CBD’s ability to calm is perhaps its most popular effect and the reason its use is so widespread. A 2017 study in the Brazilian Journal of Psychiatry tested the anxiety levels of 57 men in a simulated public speaking test. Some received a placebo while others received either 150 milligrams, 300 milligrams or 600 milligrams of CBD before their speeches. Those who received 300 milligrams of CBD experienced significantly reduced anxiety during the test compared to those who received the placebo. Interestingly, participants who received either 150 or 600 milligrams of CBD experienced more anxiety during the test than the 300 milligrams group.
2. Treat Select Epilepsy Syndromes
In 2018, in a study of more localized treatment, researchers administered a synthetic CBD gel in either 250-milligram or 500-milligram doses daily or a placebo to patients with knee pain due to osteoarthritis. Patients also stopped taking any other anti-inflammatory medications or painkillers, with the exception of acetaminophen, before and during the study period.
Margaret Rajnic, a doctor of nursing practice experienced in medical cannabis and CBD, emphasizes the importance of using therapy in tandem with any type of cannabis or CBD for PTSD. “There is an amount of therapy that is needed for PTSD,” she says. “But CBD will give you that little bit of decreased anxiety.”
In one such study, researchers administered CBD to people with heroin use disorder. Over the course of a week, CBD significantly reduced heroin users’ cue-induced cravings, withdrawal anxiety, resting heart rate and salivary cortisol levels. No serious adverse effects were found.
Unfortunately, few human trials investigating the use of CBD as a single agent to relieve pain exist, with most trials using a combination of CBD and THC to relieve pain. Notably, Health Canada has approved a combination medication that contains both THC and CBD in a 1:1 ratio for the relief of central nerve-related pain in multiple sclerosis, and cancer pain that is unresponsive to optimized opioid therapy.
Other trials of 300 mg of CBD in people with anxiety or depression showed that CBD appeared to preserve sleep architecture, meaning it was unlikely to have any negative effects on sleep quality. 10
Conclusion: CBD may be beneficial at relieving pain but no high-quality human studies prove this.
CBD derived from hemp contains no more than 0.3% THC and is legal federally but still illegal under some state laws. Cannabis-derived CBD products, on the other hand, are illegal federally but legal under some state laws.
Animal studies have shown some effect of CBD at relieving depression, possibly related to its strong anti-stress effect after either acute or repeated administration. 16
A few drops of CBD oil in a mocha or smoothie are not likely to do anything, researchers contend. Doctors say another force may also be at play in people feeling good: the placebo effect. That’s when someone believes a drug is working and symptoms seem to improve.
By Dawn MacKeen
Will these trends change your life — or
Is CBD harmful?
A recent chart review of 72 psychiatric patients treated with CBD found that anxiety improved, but not sleep. “Over all, we did not find that it panned out as a useful treatment for sleep,” said Dr. Scott Shannon, assistant clinical professor of psychiatry at the University of Colorado, Denver and the lead author of the review in The Permanente Journal.
Last year, the F.D.A. approved Epidiolex, a purified CBD extract, to treat rare seizure disorders in patients 2 years or older after three randomized, double-blind and placebo-controlled clinical trials with 516 patients that showed the drug, taken along with other medications, helped to reduce seizures. These types of studies are the gold standard in medicine, in which participants are divided by chance, and neither the subject nor the investigator knows which group is taking the placebo or the medication.
“If you take pure CBD, it’s pretty safe,” said Marcel Bonn-Miller, an adjunct assistant professor at the University of Pennsylvania’s Perelman School of Medicine. Side effects in the Epidiolex trial included diarrhea, sleepiness, fatigue, weakness, rash, decreased appetite and elevated liver enzymes. Also, the safe amount to consume in a day, or at all during pregnancy, is still not known.
This year, 1,090 people have contacted poison control centers about CBD, according to the American Association of Poison Control Centers. Over a third are estimated to have received medical attention, and 46 were admitted into a critical care unit, possibly because of exposure to other products, or drug interactions. In addition, concern over 318 animals poured into the American Society for the Prevention of Cruelty to Animals’ Animal Poison Control Center.