A prospective observational study of 522 Australian patients prescribed medicinal cannabis for chronic pain, anxiety, or PTSD found meaningful symptom improvements that were largely sustained over 12 months, according to research published in the journal Drug Science, Policy and Law. Chronic pain severity and interference scores improved within three months, anxiety scores on a standard clinical scale nearly halved on average, and PTSD severity scores also dropped substantially, with researchers reporting the gains held through the full follow-up period. The study, part of the Project Twenty21 Australia research program led by Kylie O’Brien and colleagues, had no control group, so it cannot rule out placebo effects, and it relied on largely self-reported diagnoses and validated questionnaires rather than objective measures. The authors recorded five adverse events over the study period, most involving high-THC products, and described them as mild to moderate. The researchers characterize the findings as evidence supporting further controlled study of medicinal cannabis for these conditions.