摘要：Introduction: There is growing evidence for natural recovery from cannabis use by people with psychosis, but mechanisms underpinning it need further exploration. This study prospectively explored this issue. Method: Twenty-two people with psychosis and cannabis misuse were recruited: 19 provided data for at least one follow-up assessment, and 13 of these (68%) reduced or ceased using cannabis. A semi-structured interview with the latter group explored reasons for initiating the attempt, strategies they employed, and context/s where any relapse occurred. Interpretative phenomenological analysis was used to identify themes. Results: Participants who reduced or ceased cannabis use had fewer negative symptoms at Baseline, and were more likely to only use cannabis. Major reasons for starting an attempt were worsening mental health, relationship and lifestyle difficulties. Effective strategies fell into psychological, relationship, lifestyle and medication themes. Only three participants reported a relapse: triggers involved substance-using peers, relationship difficulties, and problems with negative emotions including ones from past trauma. Conclusions: An encouragingly high rate of maintained reductions in cannabis use was seen. Increased awareness of the benefits across multiple life domains from addressing cannabis use may be critical to the initiation and maintenance of attempts, both to maximise motivation, and avoid over-dependence on improvements in any single domain. Negative symptoms, multiple substance use, dysphoria and pressure from substance-using peers clearly offer additional challenges for control.
