Each month our editorial team sifts through hundreds of papers and curates notable findings—for practitioners and informed readers who want to stay current with the evidence. Subscribe to the monthly Research Digest for expert analysis and concise summaries of key papers.
165 papers
In a small, carefully controlled study, seven people with major depression each received a single low-dose ketamine infusion on one day and a saline infusion on another day, without anyone knowing which was which. People who got ketamine showed clear improvement in their depressive symptoms within three days, while those…
In a small, controlled study of 18 people with treatment-resistant major depression, a single intravenous dose of the NMDA receptor antagonist ketamine (0.5 mg/kg) produced rapid drops in depression scores. Improvement began within about 2 hours and remained statistically significant compared with placebo for up to 1 week. The study…
Some research suggests that whole-plant cannabis compounds (like THC, CBD, other cannabinoids, terpenes, and flavonoids) can interact so the plant’s effects differ from CBD alone. Healthline explains three CBD types — full-spectrum, broad-spectrum, and isolate — and notes legal, safety, and labeling limits. The article says there is evidence for…
Researchers tested a single intravenous dose of ketamine in 73 people with major depression that had not gotten better with usual treatments. In a two-site, double-blind trial, people were randomly given either ketamine or an active placebo (the anesthetic midazolam). Twenty-four hours after the infusion, people who got ketamine were…
The endocannabinoid system (ECS) is a widespread brain signaling system made of cannabinoid receptors, naturally made lipid messengers, and the enzymes that make and break those messengers. The two best-studied messengers are 2-AG and anandamide, and they are produced and degraded by different enzyme pathways. CB1 receptors are common in…
Researchers tested a nasal spray form of esketamine together with a newly started oral antidepressant in adults whose depression had not improved after trying at least two antidepressants. Over four weeks, people who got esketamine plus a new antidepressant had faster and larger drops in depression symptoms than those who…
This review says cannabidiol (CBD) is a non‑psychoactive cannabis compound that has antioxidant and anti‑inflammatory actions in lab and some clinical studies. CBD can act directly to neutralize reactive molecules and indirectly by changing cell signals and antioxidant enzymes. Experiments in cells and animals show CBD lowers markers of oxidative…
This phase 3, double-blind trial tested whether continuing esketamine nasal spray plus an oral antidepressant could delay relapse in adults with treatment-resistant depression who had already improved after an initial esketamine course. Of 297 patients who entered the randomized phase, continuing esketamine reduced relapse compared with switching to placebo nasal…
A group of international mood-disorder experts reviewed the research on ketamine and esketamine for adults whose depression did not get better with usual antidepressants. They found that these drugs work differently from standard antidepressants and can lift symptoms more quickly for some people with treatment-resistant depression. However, the experts also…
Treatment-resistant depression means depression that does not get better after usual treatments. Scientists do not all agree on one clear definition, which makes it hard to know exactly how common it is or which treatments work best. Using the definition that regulators often use, about 30% of people with depression…
This review collected human studies on how cannabidiol (CBD) is absorbed, distributed, and cleared. From 792 records, 24 studies reported pharmacokinetic (PK) data. Results varied by how CBD was given and by formulation. For example, smoking produced faster and higher blood levels than oral or oromucosal routes. The authors concluded…
This CDC analysis used the 2019–2021 National Health Interview Survey to estimate how common chronic pain is among U.S. adults. In 2021, about 20.9% of adults (51.6 million people) reported pain on most days or every day for the past three months. About 6.9% (17.1 million people) had high-impact chronic…
