Pre-treatment with 600 mg of cannabidiol (CBD) reduced the likelihood of clinically significant psychotic symptoms and paranoia caused by intravenous delta-9-tetrahydrocannabinol (THC, 1.5 mg) in healthy volunteers. Participants who received CBD before THC had lower scores on the State Social Paranoia Scale and smaller declines in episodic memory compared with those who received placebo before THC. The odds of experiencing a clinically significant increase in positive psychotic symptoms were about 78% lower in the CBD group. These results support the view that cannabis products high in THC and low in CBD pose greater mental health risks.
MDMA (Ecstasy) tablets collected in the UK between 2001 and 2018 show increasing MDMA content over time, with median free-base content exceeding 100 mg for the first time in 2018. Analysis of 412 tablets revealed dramatic within-batch content variability, with differences up to 136 mg. Dissolution testing on 247 tablets showed that tablets can be categorized as fast-, intermediate-, or slow-releasing, but no tablet characteristics predicted dissolution classification, meaning users cannot know a tablet's release profile beforehand. Within-batch variation in dissolution rate was also observed. Rapid assessment of MDMA content alone does not account for variability in remaining tablets in a batch or dissolution profiles. High-content, slow-releasing tablets may cause delayed or prolonged toxicity, increasing risk of re-dosing if absorption is delayed.