{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T17:37:12Z","timestamp":1788975432877,"version":"build-2803163510"},"reference-count":25,"publisher":"Oxford University Press (OUP)","issue":"12","license":[{"start":{"date-parts":[[2025,12,15]],"date-time":"2025-12-15T00:00:00Z","timestamp":1765756800000},"content-version":"vor","delay-in-days":17,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"name":"Canadian Institutes of Health Research Project","award":["CIHR PS 159668"],"award-info":[{"award-number":["CIHR PS 159668"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,11,28]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Cannabinoids interact with multiple drugs, with some interactions having significant clinical effects.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>This study aimed to evaluate amongst older people (i) the trends in the concomitant medical use of cannabis and drugs associated with a risk of significant clinical interaction with cannabinoids (DARSCIC), including those with a narrow therapeutic index (drugs with a narrow therapeutic index; DNTI) such as warfarin, and (ii) the risk of bleeding, drug-related intoxication, thyrotoxicosis and major cardiovascular events.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>For objective 1, we conducted an interrupted time series study amongst 12\u00a0599 seniors who received an authorised cannabis prescription in Ontario from 2014\u20132019. Using clinical and medico-administrative data, dispensations of DARSCIC were assessed pre-post cannabis prescription. For objective 2, longitudinal cohort studies were conducted in patients concomitantly exposed to cannabis and warfarin (bleeding) or to DNTI (intoxication) versus controls.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>For objective 1, the trends of DARSCIC\/DNTI dispensations were similar in the year before and after cannabis prescription. For objective 2, amongst 378 patients exposed to cannabis and warfarin, the risk of bleeding was 1.19, 95%CI (0.71\u20131.98), compared to 1646 controls. The risk of drug-related intoxication was 2.61, 95%CI (1.42\u20134.79) amongst 3926 patients exposed to cannabis and DNTI compared to 12\u00a0223 controls. Patients exposed to cannabis and levothyroxine (n\u2009=\u20092499) had a significantly higher risk of heart failure but not thyrotoxicosis, acute coronary syndrome or stroke.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>These findings indicate that prescribing practices for cannabis may not adequately consider the implications of DARSCIC\/DNTI. Enhancing prescriber awareness of these interactions could mitigate the risk of adverse effects such as drug-related intoxication.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ageing\/afaf359","type":"journal-article","created":{"date-parts":[[2025,12,6]],"date-time":"2025-12-06T12:58:19Z","timestamp":1765025899000},"source":"Crossref","is-referenced-by-count":1,"title":["Concomitant use of medical cannabis and drugs associated with risks of interaction in older patients: a longitudinal cohort study"],"prefix":"10.1093","volume":"54","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1263-5623","authenticated-orcid":false,"given":"Zoumana Cheick","family":"B\u00e9r\u00e9t\u00e9","sequence":"first","affiliation":[{"name":"Faculty of Pharmacy, Universit\u00e9 Laval , Qu\u00e9bec City, Quebec ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arvis Abraham","family":"Sebgo","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Universit\u00e9 Laval , Qu\u00e9bec City, Quebec ,","place":["Canada"]},{"name":"Population Health and Optimal Health Practices Research Axis, Centre Hospitalier Universitaire de Qu\u00e9bec\u2014Universit\u00e9 Laval Research Centre , Qu\u00e9bec City, Quebec ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2197-0463","authenticated-orcid":false,"given":"Dean T","family":"Eurich","sequence":"additional","affiliation":[{"name":"School of Public Health, University of Alberta , Edmonton, Alberta ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6465-8686","authenticated-orcid":false,"given":"Cerina","family":"Dubois","sequence":"additional","affiliation":[{"name":"School of Public Health, University of Alberta , Edmonton, Alberta ,","place":["Canada"]},{"name":"Department of Mental Health, Johns Hopkins University , Baltimore, Maryland ,","place":["USA"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7045-2884","authenticated-orcid":false,"given":"Jason R","family":"Dyck","sequence":"additional","affiliation":[{"name":"Faculty of Medicine and Dentistry, University of Alberta , Edmonton, Alberta ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"John G","family":"Hanlon","sequence":"additional","affiliation":[{"name":"St. Michael\u2019s Hospital Department of Anesthesia, University of Toronto , Toronto, Ontario ,","place":["Canada"]},{"name":"Department of Anaesthesiology and Pain Medicine, University of Toronto , Toronto, Ontario ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8812-3088","authenticated-orcid":false,"given":"Arsene","family":"Zongo","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Universit\u00e9 Laval , Qu\u00e9bec City, Quebec ,","place":["Canada"]},{"name":"Population Health and Optimal Health Practices Research Axis, Centre Hospitalier Universitaire de Qu\u00e9bec\u2014Universit\u00e9 Laval Research Centre , Qu\u00e9bec City, Quebec ,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2025,12,15]]},"reference":[{"key":"2025121511541256300_ref1","doi-asserted-by":"publisher","first-page":"1509","DOI":"10.1007\/s00213-021-06047-8","article-title":"Prevalence and self-reported reasons of cannabis use for medical purposes in USA and Canada","volume":"239","author":"Leung","year":"2022","journal-title":"Psychopharmacology (Berl)"},{"key":"2025121511541256300_ref2","first-page":"65","volume-title":"National Estimates of Marijuana Use and Related Indicators\u2014National Survey on Drug Use and Health, United States, 2002\u20132014. 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