Skip to content

Joshua C Black

Karilynn M. Rockhill and Alison Abraham are with the Department of Epidemiology, University of Colorado Anschutz Medical Campus, Aurora, CO. Karilynn M. Rockhill, Joshua C. Black, and Janetta Iwanicki are with Rocky Mountain Poison & Drug Safety, Denver Health & Hospital Authority, Denver, CO.

6 papers in the library · 44 citations · publishing 2024-2026

Papers

Polysubstance Use Profiles Among the General Adult Population, United States, 2022.

American journal of public health May 1, 2025 Karilynn M Rockhill, Joshua C Black, Janetta Iwanicki et al. 17 citations

In a 2022 nationally representative US survey of 15,800 adults, 20.9% reported using two or more drugs in the past year. Four distinct patterns emerged: medically guided use (11.5% of adults, 6.1% with substance use disorder), principal cannabis use (4.0%, 31.9% with disorder), self-guided nonmedical use (3.4%, 14.5% with disorder), and indiscriminate coexposures (2.1%, 58.9% with disorder). The findings reveal two previously unrecognized classes and indicate that many adults with polysubstance use have untreated substance use disorders. Prevention and treatment should be personalized to each person's specific drug-use profile.

Clinical Effects of Psychedelic Substances Reported to United States Poison Centers: 2012 to 2022.

Annals of emergency medicine December 1, 2024 Mark W Simon, Heather A Olsen, Christopher O Hoyte et al. 12 citations

Over half of psychedelic exposures reported to US poison centers resulted in symptoms that required treatment, severe residual or prolonged symptoms, or death. From 2012 to 2022, 54,605 cases were recorded, with hallucinogenic mushroom exposures rising most sharply from 593 to 1,440. Cardiovascular effects were common, especially with hallucinogenic amphetamines (31.1%). Among patients managed in healthcare facilities, 62.4% received medical therapies, including sedation (32.9%) and respiratory interventions (10.3%). Concomitant exposures occurred in 41.1% of cases. Increasing psychedelic use may lead to more adverse events and healthcare utilization.

Trends in poisonings involving ketamine in the United States, 2019-2023.

Drug and alcohol dependence March 1, 2025 Joseph J Palamar, Jennifer S Jewell, Omar El-Shahawy et al. 9 citations

Reported ketamine poisonings in the US rose from 205 in 2019 to 414 in 2023, the highest in reporting history. Most cases involved ingestion (57.2%) and misuse or abuse (36.2%). The proportion of cases involving suspected suicide attempts doubled from 12.7% to 25.9%, and ingestion increased from 46.0% to 65.2%. Cases with major effects or death decreased from 23.4% to 15.6%. Overall, 18.6% of cases experienced a major event or death, but prevalence was lower for those who inhaled ketamine compared to those who did not. Both medical and recreational use and related adverse events need monitoring, especially as off-label prescribing of take-home oral formulations appears to be increasing.

Psychedelic Trips: Travel Within the United States to Use Psychedelic Drugs After Legalization.

Annals of emergency medicine June 30, 2025 Joshua C Black, Karilynn M Rockhill, Evelyn J Fox et al. 4 citations

About one-third of US adults who used psychedelics in the past year traveled out of state to do so, primarily to Colorado and Oregon, which have decriminalized natural psychedelics. Travelers were more likely than nontravelers to report anxiety or depression symptoms and to have visited an emergency department or urgent care for a psychedelic-related issue. They were also more likely to use psychedelics for medical symptoms, at healing centers, or at ceremonial sites. Emergency physicians in both legalized and nonlegal states should be aware that travel for psychedelic use is common and may carry risks of adverse outcomes.

Fusing Specialized Surveys of Rare Populations to Larger Surveys for Generalized Inference: Cross-Sectional Survey Study.

Journal of medical Internet research April 27, 2026 Karilynn M Rockhill, Elizabeth A Bemis, Nicole Schow et al. 2 citations

Combining a large representative survey with a smaller survey focused on psychedelic drugs can produce generalizable estimates of rare behaviors like drug use without adding burdensome questions to the big survey. Researchers used calibration weighting to transport estimates from a psychedelic-enriched survey (two waves, total over 4,300 adults) to a representative anchor survey (two waves, total over 57,000 adults). The method showed good internal consistency, with transport biases under 0.4 percentage points for demographics, health, and substance use. External validity improved for health and substance use estimates after fusion. Using the fused data, recreational use of psilocybin (92.9%), LSD (93.2%), and MDMA (93.3%) was far more common than medical use (30.9%, 26.4%, and 21.1%, respectively). This approach expands surveillance epidemiology for rare behaviors.

Psychedelic Terminology Preference in the 2024 National Survey Investigating Hallucinogenic Trends (NSIHT).

Journal of psychoactive drugs March 16, 2026 Faith E Lyons, Karilynn M Rockhill, Evelyn J Fox et al.

Adults who used a psychedelic in the past year most prefer surveys that use specific substance names (e.g., psilocybin, ayahuasca) over umbrella terms. In a cross-sectional survey of 2,306 respondents, specific substance names received the highest preference (median rank 3; 24.3% ranked first), followed by "psychedelics" (median rank 3; 19.4%). Terms like "hallucinogen," "medicines," and "entheogens" ranked lower. Preferences were consistent across age, education, and experience levels. The findings offer recommendations for terminology in future survey development.