Animal studies have shown that CBD has a positive effect on serotonin levels in the brain, and serotonin. Low levels of serotonin are thought to play a key role in mood as well as pain. 11
CBD has also been investigated for use in other forms of treatment-resistant epilepsy, usually in addition to conventional epilepsy medications. Results varied, but several trials showed CBD significantly reduced seizure frequency by almost 44% in most people. 3
In June 2018, the FDA approved Epidiolex (a plant-based formulation of CBD) to treat seizures for people 2 years of age and older with Dravet syndrome and Lennox-Gastaut syndrome (LGS), which are two rare forms of epilepsy.
Conclusion: CBD does not appear to interfere with sleep and may help people sleep better.
Conclusion: Topical CBD may be beneficial at relieving arthritis but no high-quality human studies prove this.
Many soldiers return home haunted by war and PTSD and often avoid certain activities, places or people associated with their traumatic events. The Department of Veterans Affairs is funding its first study on CBD, pairing it with psychotherapy.
Dr. Smita Das, chair of the American Psychiatric Association’s Council on Addiction Psychiatry’s cannabis work group, does not recommend CBD for anxiety, PTSD, sleep or depression. With patients turning to these to unproven products, she is worried that they may delay seeking appropriate mental health care: “I’m dually concerned with how exposure to CBD products can lead somebody into continuing to cannabis products.”
Sleep can be disrupted for many reasons, including depression. Rodents seemed to adapt better to stressful conditions and exhibited less depressive-like behavior after taking CBD, according to a review in Journal of Chemical Neuroanatomy. “Surprisingly, CBD seems to act faster than conventional antidepressants,” wrote one of the authors of a new review, Sâmia Joca, a fellow at the Aarhus Institute of Advanced Studies in Denmark and an associate professor at the University of São Paulo in Brazil, in an email interview. Of course, it’s difficult to detect depression in animals, but the studies that Ms. Joca and her colleagues reviewed suggested that in models of chronic stress exposure, the mice and rats treated with CBD were more resilient.
Does CBD help anxiety and PTSD?
However, a double-blind study found healthy volunteers administered CBD had little to no change in their emotional reaction to unpleasant images or words, compared to the placebo group. “If it’s a calming drug, it should change their responses to the stimuli,” said Harriet de Wit, co-author of the study and a professor in the University of Chicago’s department of psychiatry and behavioral neuroscience. “But it didn’t.”
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.
“Our top therapies attempt to break the association between reminders of the trauma and the fear response,” said Mallory Loflin, an assistant adjunct professor at the University of California, San Diego and the study’s principal investigator. “We think that CBD, at least in animal models, can help that process happen a lot faster.” While large clinical trials are underway, psychologists say there isn’t compelling evidence yet as to whether this is a viable treatment.
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.
CBD shows promise in the treatment of anxiety disorders, suggests a 2015 review of studies in the journal Neurotherapeutics. According to the investigators, CBD demonstrated potent anxiolytic (anxiety-relieving) effects in animal research, albeit with counterintuitive results.
Proponents claim that CBD oil can treat a wide variety of health problems, including:
Outside of these two disorders, CBD’s effectiveness in treating seizures is uncertain. Even with Epidiolex, it is uncertain whether the anti-seizure effects can be attributed to CBD or some other factor.
Instead, CBD is thought to influence other receptors, including opioid receptors that regulate pain and glycine receptors involved in the regulation of the “feel-good” hormone and neurotransmitter serotonin.
In addition, the stroke volume (the amount of blood remaining in the heart after a heartbeat) was significantly reduced, meaning that the heart was pumping more efficiently.