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The Effect of Inhaled Cannabis on Intraocular Pressure in Healthy Adult Subjects
Abstract:
Overview
Purpose: To study the effect of inhaled cannabis on intraocular pressure (IOP) in healthy adult subjects. Design: Prospective, double-blind, randomized, placebo-controlled trial. Methods: Study participants were randomized to receive a single dose of inhaled cannabis or placebo in an 11:3 ratio. Subjects self-administered inhaled cannabis or placebo cigarette in negative-pressure rooms. Measurements of IOP, systemic blood pressure, and plasma tetrahydrocannabinol levels were taken at baseline and every 40 minutes for 2 hours, and afterwards, every hour for 3 hours. Paired T-test was performed on the IOP readings to compare the treatment group with the placebo group, and with baseline readings. Results: A total of 14 participants were included. Average baseline IOP for the treatment group and placebo group was 17.5 mmHg and 18.4 mmHg, respectively. IOP was significantly lowered from baseline in the treatment group at all time points post-treatment, up to the 4-hour time point. The placebo group had extensive IOP fluctuations and had a significant IOP reduction only at the 80-minute, 3-hour, and 5-hour time points. IOP was not significantly different between placebo and treatment groups. Peak IOP lowering occurred at the 80-minute time point with 15.7% reduction in IOP in the treatment group. There were no significant changes in systemic blood pressure during the duration of the study. Conclusions: Cannabis lowers IOP significantly from baseline in adult healthy subjects. This effect is detected from 40 minutes post-treatment and lasts up to 4 hours. Systemic blood pressure was not significantly affected.
Keywords
Intraocular pressure, cannabis blood pressure
Article:
Article Information:
Disclosure
Sameh Mosaed, John HK Liu, Donald S Minckler, Robert L Fitzgerald, David Grelotti, Barth Wilsey, Emily Sones, Robert N Weinreb, and Thomas D Marcotte have no financial or non-financial relationships or activities to declare in relation to this article.
Compliance With Ethics
All procedures were followed in accordance with the responsible committee on human experimentation and with the Helsinki Declaration of 1975 and subsequent revisions, and informed consent was received from the patient involved in this case study.
Review Process
Double-blind peer review.
Authorship
The named authors meet the International Committee of Medical Journal Editors (ICMJE) criteria for authorship of this manuscript, take responsibility for the integrity of the work as a whole, and have given final approval for the version to be published.
Correspondence
Sameh Mosaed, Gavin Herbert Eye Institute, University of California, 850 Health Sciences Road, Irvine, CA 92697-4375, USA. E: smosaed@hs.uci.edu
Support
This study was conducted using departmental funds from the University of California, Irvine, Gavin Herbert Eye Institute.
Open Access
This article is freely accessible at touchOPHTHALMOLOGY.com. © Touch Medical Media 2020
Received
2020-08-10