{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,25]],"date-time":"2026-02-25T20:04:20Z","timestamp":1772049860932,"version":"3.50.1"},"reference-count":35,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,10,14]],"date-time":"2021-10-14T00:00:00Z","timestamp":1634169600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Cannabis products that contain the tetrahydrocannabinol (THC) cannabinoid are emerging as promising therapeutic agents for the treatment of medical conditions such as chronic pain. THC elicits psychoactive effects through modulation of dopaminergic neurons, thereby altering levels of dopamine in the brain. This case report highlights the complexity associated with medicinal cannabis and the health risks associated with its use. A 57-year-old male with Parkinson\u2019s disease was experiencing worsening tremors and vivid hallucinations despite therapy optimization attempts. It was discovered that the patient took cannabis for chronic back pain, and a pharmacogenomics (PGx) test indicated the presence of variants for the COMT and HTR2A genes. These variants could increase dopamine levels and predispose patients to visual hallucinations. Once the cannabis was discontinued, the patient\u2019s hallucinations began to slowly dissipate. Cannabis use continues to expand as it gains more acceptance legally and medicinally, but cannabis can affect the response to drugs. This patient case suggests that cannabis use in combination with dopamine-promoting drugs, especially in a patient with genetic variants, can increase the risk for vivid hallucinations. These conditions support the importance of considering herb\u2013drug interactions and PGx data when performing a medication safety review.<\/jats:p>","DOI":"10.3390\/medicina57101107","type":"journal-article","created":{"date-parts":[[2021,10,14]],"date-time":"2021-10-14T22:42:18Z","timestamp":1634251338000},"page":"1107","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Cannabis Dopaminergic Effects Induce Hallucinations in a Patient with Parkinson\u2019s Disease"],"prefix":"10.3390","volume":"57","author":[{"given":"Katie","family":"Pizzolato","sequence":"first","affiliation":[{"name":"Office of Translational Research and Residency Programs, Tabula Rasa HealthCare, Moorestown, NJ 08057, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David","family":"Thacker","sequence":"additional","affiliation":[{"name":"Tabula Rasa HealthCare, Precision Pharmacotherapy Research and Development Institute, Tabula Rasa HealthCare, Orlando, FL 32827, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nicole Del","family":"Toro-Pag\u00e1n","sequence":"additional","affiliation":[{"name":"Office of Translational Research and Residency Programs, Tabula Rasa HealthCare, Moorestown, NJ 08057, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abeer","family":"Hanna","sequence":"additional","affiliation":[{"name":"Viecare Butler, Program of All-Inclusive Care for the Elderly (PACE), Butler, PA 16001, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7978-9280","authenticated-orcid":false,"given":"Jacques","family":"Turgeon","sequence":"additional","affiliation":[{"name":"Tabula Rasa HealthCare, Precision Pharmacotherapy Research and Development Institute, Tabula Rasa HealthCare, Orlando, FL 32827, USA"},{"name":"Faculty of Pharmacy, Universit\u00e9 de Montr\u00e9al, Montr\u00e9al, QC H3C 3J7, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7448-9799","authenticated-orcid":false,"given":"Adriana","family":"Matos","sequence":"additional","affiliation":[{"name":"Office of Translational Research and Residency Programs, Tabula Rasa HealthCare, Moorestown, NJ 08057, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nishita","family":"Amin","sequence":"additional","affiliation":[{"name":"Office of Translational Research and Residency Programs, Tabula Rasa HealthCare, Moorestown, NJ 08057, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Veronique","family":"Michaud","sequence":"additional","affiliation":[{"name":"Tabula Rasa HealthCare, Precision Pharmacotherapy Research and Development Institute, Tabula Rasa HealthCare, Orlando, FL 32827, USA"},{"name":"Faculty of Pharmacy, Universit\u00e9 de Montr\u00e9al, Montr\u00e9al, QC H3C 3J7, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,14]]},"reference":[{"key":"ref_1","unstructured":"Banerjee, S., and McCormack, S. 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