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Krista J Siefried

St. Vincent's Hospital Alcohol and Drug Service, St. Vincent's Hospital, Sydney, NSW, Australia.

4 papers in the library · 2 citations · publishing 2025-2026

Papers

'A fine line between euphoria and death': a qualitative study exploring gamma-hydroxybutyrate (GHB) use among people who identify as heterosexual living in Australia.

Harm reduction journal February 6, 2026 Keaton Hudson-Buhagiar, Jonathan Brett, Alanah Spillane et al. 1 citation

Among heterosexual Australians who use GHB, three patterns of use—occasional, regular, or daily—emerged. Four key themes were identified: escapism (managing mental health symptoms, enhancing confidence, facilitating sex, and alleviating body consciousness in women); diverse understandings of overdose, including intentional dosing to achieve unconsciousness and misconceptions about using stimulants to counter toxicity, with fear of police delaying help-seeking; stigma from both drug-using and non-using peers; and gendered harm reduction practices where women protect each other from harms, especially sexual violence. Findings point to gaps in public health education on overdose management and intentional risk-taking.

Protocol of an open-label safety and feasibility pilot study of ketamine-assisted psychotherapy for methamphetamine use disorder (the KAPPA trial).

BMJ open February 10, 2025 Kathryn Fletcher, Nadine Ezard, Krista J Siefried et al. 1 citation

A pilot study will test the safety and feasibility of combining subanaesthetic ketamine with cognitive behavioural therapy for adults with methamphetamine use disorder. Twenty participants seeking to reduce or stop methamphetamine use will receive three subcutaneous ketamine doses (0.75 to 0.9 mg/kg) at weekly intervals and four therapy sessions over four weeks. The study will measure recruitment time, eligibility rates, treatment completion, retention, and acceptability over eight weeks, and explore changes in methamphetamine use, cravings, withdrawal, quality of life, and treatment satisfaction over 24 weeks. No pharmacological treatments currently exist for this condition, and psychotherapy alone is only moderately effective.

"Large-Scale and Local Functional Connectivity Changes Following Psilocybin Administration in Methamphetamine Use Disorder.

AJNR. American journal of neuroradiology April 24, 2026 Joga Chaganti, Krista J Siefried, Veda S Vyakaranam et al.

In individuals with methamphetamine use disorder, psilocybin administration alongside psychotherapy led to measurable reorganization of large-scale brain networks and local neural synchrony. After the intervention, connectivity within and between attentional, default mode, and salience networks shifted significantly, and local synchrony increased in frontal and sensorimotor regions. Greater reductions in methamphetamine use correlated with recovery of frontostriatal and attentional connectivity, while reduced psychological distress was linked to strengthened integration of attentional and prefrontal-striatal circuits. These findings suggest psilocybin may promote network-level plasticity in stimulant addiction and support the potential of resting-state fMRI metrics as biomarkers of such change.

Exploring the Utility and Appropriateness of Dose Thresholds for Issuing of Public Drug Alerts on High-Dose MDMA: A Qualitative Study.

Drug and alcohol review March 1, 2026 Jack Freestone, Harriet MacDonald, Stassi Kypri et al.

Drug alerts in Australia are triggered when MDMA pills contain at least 150 mg of free-base MDMA, a threshold experts consider reasonable despite its limitations. Nineteen such alerts were issued in 2024, raising concerns about diminishing impact. Fifteen experts who design and disseminate drug alerts completed a survey, and seven participated in a focus group. Most agreed 150 mg is a reasonable threshold because it enables rapid communication and addresses potential harm, though thresholds cannot account for evolving manufacturing or consumption trends. Limited capacity to monitor community perceptions means there is little evidence to justify changing the threshold. Notifying communities about high-dose MDMA remains a harm-reduction priority; improving monitoring and establishing a dosage database could enhance future risk communication.