Protocol for a mobile laboratory study of co-administration of cannabis concentrates with a standard alcohol dose in humans

Correction: Protocol for a mobile laboratory study of co-administration of cannabis concentrates with a standard alcohol dose in humans

[This corrects the article DOI: 10.1371/journal.pone.0277123.].

Simultaneous cannabis and psychedelic use among festival and concert attendees in Colorado: characterizing enhancement and adverse reactions using mixed methods

BACKGROUND

Most studies examining the simultaneous use of cannabis with other drugs have focused on cannabis and alcohol, with fewer studies examining simultaneous use of cannabis with other drugs. The United States is currently experiencing an upward trend in psychedelic use and there is an increasing need to characterize cannabis and psychedelic drug interactions to best inform public health recommendations.

MATERIALS AND METHODS

A mixed methods field study design was used to survey participants (N = 128) on their lifetime co-use of cannabis with other drugs. Participants who reported lifetime co-use of cannabis and psychedelics (N = 63) were then asked open-ended questions about their most recent simultaneous co-use experience (i.e., how cannabis enhanced their psychedelic experience and whether they experienced any adverse reactions). We conducted a thematic analysis of responses describing how cannabis enhanced the psychedelic experience (N = 54). However, due to low response rate for participants reporting an adverse reaction (N = 7, 11.1%), responses to this question were not analyzed thematically and are instead presented individually.

RESULTS

Themes included tension reduction and balancing of drug effects (N = 27, 50%), enhancement to psychological processes (N = 11, 20.4%), intensified psychedelic drug effects (N = 12, 22.2%), enhanced psychedelic come-down experience (N = 8, 14.8%), and overall ambiguous enhancement (N = 7, 13%). Among participants reporting an adverse reaction, individual responses included increased anxiety and intensity of the experience, decreased sociability, increased negative affect, sleepiness, disassociation, and confusion.

CONCLUSION

Additional research is warranted to better characterize cannabis and psychedelic drug interactions to best inform public health recommendations.

The Reddit cannabis subjective highness rating scale: Applying computational social science to explore psychological and environmental correlates of naturalistic cannabis use

Social media data provide unprecedented access to discussions of active, naturalistic, and often real-time cannabis use in an era of cannabis policy liberalization. The aim of this study was to explore psychological and environmental correlates of cannabis effects by applying computational social science approaches to a large dataset of unprompted reports of naturalistic cannabis use with corresponding self-reported numerical ratings of subjective highness. Post title text was extracted via the Pushshift dataset from N = 328,865 posts to the r/trees Reddit community, where posters self-assess and disclose how high they feel on a scale from 1 to 10 (M = 6.9, SD = 1.8). Structural topic modelling and Linguistic Inquiry and Word Count (LIWC) dictionary-based approaches were applied to identify (1) frequently discussed topics and (2) text indicative of 5 psychological processes (affective, social, cognitive, perceptual, biological), respectively, as well as to examine relationships between subjective highness and (1) topic prevalence and (2) psychological process word counts. A 40-topic model was selected for interpretation based on semantic coherence and exclusivity. The most discussed topics in a 40-topic model were characterized by references to smoking places, social contexts, positive affect, cognitive states, as well as food and media consumed. In LIWC dictionary analyses, words mentioning affective, social, and cognitive processes were referenced more often than perceptual or body processes. Posters reported greater subjective highness when using language that referred to in-person social environments and lower subjective highness when using language that referred to online social environments and positive affect psychological states. This examination of unprompted online reports of naturalistic cannabis use identified textual content referring to affect and to other people as being associated with perceived effects of cannabis. These affective and social aspects of the cannabis use experience were salient to active posters in this online community and should be integrated into experience sampling methods and behavioral pharmacology research, as well as public health messaging.

The effects of simultaneous alcohol and cannabis use on subjective drug effects: A narrative review across methodologies

Over 75% of young adults who use cannabis also report drinking alcohol, leading to increased risks that include impaired cognition, substance use disorders, and more heavy and frequent substance use. Studies suggest that subjective responses to either alcohol or cannabis can serve as a valuable indicator for identifying individuals at risk of prolonged substance use and use disorder. While laboratory studies show additive effects when alcohol and cannabis are used together, the impact of co-using these substances, specifically with respect to cannabidiol, on an individual's subjective experience remains unclear. This narrative review explores the effects of simultaneous alcohol and cannabis (SAM) use on subjective drug effects, drawing from qualitative research, laboratory experiments, and naturalistic studies. Experimental findings are inconsistent regarding the combined effects of alcohol and cannabis, likely influenced by factors such as dosage, method of administration, and individual substance use histories. Similarly, findings from qualitative and naturalistic studies are mixed regarding subjective drug effects following SAM use. These discrepancies may be due to recall biases, variations in assessment methods, and the measurement in real-world contexts of patterns of SAM use and related experiences. Overall, this narrative review highlights the need for more comprehensive research to understand more fully subjective drug effects of SAM use in diverse populations and settings, emphasizing the importance of frequent and nuanced assessment of SAM use and subjective responses in naturalistic settings.