E.B. Russoa, , , A. Merzoukib, c, J.Molero Mesab, K.A. Freyd, P.J. Bache
- a 2235 Wylie Avenue, Missoula, MT 59802, USA
- b Department of Botany, Faculty of Pharmacy, University of Granada, Granada 18071, Spain
- c Laboratory of Ethnobotany, Faculty of Sciences, University Abdelmalek Essaadi, Tétouan, Morocco
- d Montana State University School of Nursing, 236 Corbin Hall, University of Montana, Missoula, MT 59812, USA
- e Montana Neurobehavioral Specialists, 900 North Orange St., Missoula, MT 59802, USA
Abstract
Previous reports have documented an improvement in night vision among Jamaican fishermen after ingestion of a crude tincture of herbal cannabis, while two members of this group noted that Moroccan fishermen and mountain dwellers observe an analogous improvement after smoking kif, sifted Cannabis sativa mixed with tobacco (Nicotiana rustica). Field-testing of night vision has become possible with a portable device, the LKC Technologies Scotopic Sensitivity Tester-1 (SST-1). This study examines the results of double-blinded graduated THC administration 0–20 mg (as Marinol®) versus placebo in one subject on measures of dark adaptometry and scotopic sensitivity. Analogous field studies were performed in Morocco with the SST-1 in three subjects before and after smoking kif. In both test situations, improvements in night vision measures were noted after THC or cannabis. It is believed that this effect is dose-dependent and cannabinoid-mediated at the retinal level. Further testing may assess possible clinical application of these results in retinitis pigmentosa or other conditions.
Keywords:
Cannabis, Medical marijuana, Ethnobotany, Night vision, Ophthalmology, Visual testing
Figures and tables from this article:
- Fig. 1. Field of cannabis growing near Zoumi, Rif Mountains, Morocco, June 2002.
- Fig. 2. High-grade sifted Moroccan cannabis supports combustion.
- Fig. 3. Kif, a Cannabis sativa/Nicotiana rustica mixture in sebsi pipe.
- Fig. 4. Experimental test subject with LKC SST-1 device in background.
- Fig. 5. Dark Adapted Limit (dB) vs. Marinol® dose. No changes are noted as this subject was sufficiently sensitive as to still perceive the stimulus at the lowest instrument setting.
- Fig. 6. Scotopic Sensitivity Limit (dB) vs. Marinol® dose. A decrement in sensitivity is observed at 10 and 20 mg of Marinol. See texts for details.
- Fig. 7. Dark Adaptation Limit (dB) before and after cannabis smoking. A decrement of 1 dB is noted in each subject after smoking kif. This result would be distinctly unlikely due to chance. See text for details.
- Fig. 8. Scotopic Sensitivity Limit (dB) before and after cannabis smoking. A decrement of 1 dB is noted in two subjects and 2 dB in a third subject after smoking kif. This result is statistically significant (P<0.05). See text for details.
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Copyright © 2004 Elsevier Ireland Ltd. All rights reserved.
