Cannabis is a very convoluted plant in terms of how it works in the body. There are more than a hundred active compounds in the plant. Most of these are cannabinoids (like CBD and THC) and also terpinoids.

Each one of these compounds produces its own unique benefits. This makes it rather complicated to learn exactly which substance is causing which benefit.

Cannabis compounds have been proven to help increase the speed at which the eye responds to stimuli. This is because of the cannabinoids binding with CB1 receptors in the endocannabinoid system. Once there, they would inhibit the production of a protein called NKCC1. This protein helps to transport chloride ions in and out of cells, determining the flow of electricity between them.

Inhibiting this protein seems to produce an increase in visual response timing. By reducing the concentration of chloride ions in the cells of the retina, they become more easily excited. The result of this is that they become more receptive to light.

This effect is dose-dependent, meaning that the amount of cannabis you use is directly correlated to the increase in visual acuity.

Cannabinoids interact with receptors in the endocannabinoid system.

These receptors, especially the CB1 and CB2 receptors, are found in large numbers in parts of the brain and body that regulate pain signaling. Such areas include the dorsal root ganglia, the spinal cord, and the thalamus.

When the receptors in these areas are activated by cannabinoids, the result is analgesia: pain relief.

Cannabinoids can help reduce inflammation, encourage the body to produce endorphins, and ramp up the production of anandamide, an endocannabinoid  that helps to reduce pain signaling.

 

Researchers have been interested in creating THC eye drops for quite some time. However, production was slow because of a fundamental challenge: THC doesn’t mix well with water and is much better dissolved in oil or alcohol.

For THC to be useful in the eyes, it needs to be able to penetrate the eye’s tear layer. This tear layer consists mostly of water and thus, THC oil cannot be used directly on the eye with much benefit.

Doing this might be useful for surface-level eye discomfort, but without traveling through the tear layer, it won’t be useful for managing conditions that affect the deeper layers of the eye. THC must be dissolved in water if the compound is to reach the cornea, where it can provide benefits.

 

For THC eye drops, HEDISYN had to ‘microencapsulate’ their THC at a size so small that it became soluble in water. This is essentially how any “water-soluble” or nano THC products work.

 

By engineering THC to be no larger than 300 nanometers and dubbing it a ‘nano-cannabinoid,’ HEDISYN produced a form of THC that wasn’t just more bioavailable than usual; it was actually capable of being absorbed into the eye.

 HEDISYN HEYE Drops travel not just to the cornea but through all the different layers of your eyes. It can reach all the way through to your optic nerve. This would make the THC able to help provide relief from eye conditions of many different types.

 

 

References

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2. Vaajanen A, Vapetalo H. A Single Drop in the Eye – Effects on the Whole Body?. Open Ophthalmol J. 2017;11:305-314. Published 2017 Oct 31. doi:10.2174/1874364101711010305 []

3. Adelli, Goutham & Bhagav, Prakash & Repka, M.A. & Gul, Waseem & Elsohly, Mahmoud & Majumdar, S.. (2017). Chapter 78. Ocular Delivery of Tetrahydrocannabinol.10.1016/B978-0-12-800756-3.00089-2 []

4. Thomas Schwitzer, Raymund Schwan, Karine Angioi-Duprez, Anne Giersch, Vincent Laprevote, “The Endocannabinoid System in the Retina: From Physiology to Practical and Therapeutic Applications“, Neural Plasticity, vol. 2016, Article ID 2916732, 10 pages, 2016 [] []

5. Sally Miller, Laura Daily, Emma Leishman, Heather Bradshaw, Alex Striker; Δ9-Tetrahydrocannabinol and Cannabidiol Differentially Regulate Intraocular Pressure. Invest. Ophthalmol. Vis. Sci. 2018;59(15):5904-5911 []

6. Tomida I, Azuara-Blanco A, House H, Flint M, Pertwee RG, Robson PJ. Effect of sublingual application of cannabinoids on intraocular pressure: a pilot study.JGlaucoma.2006Oct;15(5):349-53 []

7. National Academies of Sciences, Engineering, and Medicine; Health and Medicine Division; Board on Population Health and Public Health Practice; Committee on the Health Effects of Marijuana: An Evidence Review and Research Agenda. The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations for Research. Washington (DC): National Academies Press (US); 2017 Jan 12. 4, Therapeutic Effects of Cannabis and Cannabinoids  []

8. Penn JS, Madan A, Caldwell RB, Bartoli M, Caldwell RW, Hartnett ME. Vascular endothelial growth factor in eye disease. Prog Retin Eye Res. 2008;27(4):331-371. doi:10.1016/j.preteyeres.2008.05.001 []

9. Aiello F, Gallo Afflitto G, Li JO, Martucci A, Cesareo M, Nucci C. CannabinEYEds: The Endocannabinoid System as a Regulator of the Ocular Surface Nociception, Inflammatory Response, Neovascularization, and Wound Healing. J Clin Med. 2020;9(12):4036. Published 2020 Dec 14. doi:10.3390/jcm9124036 []

10. Cairns, E., Toguri, J., Porter, R., Szczesniak, A. & Kelly, M. (2016). Seeing over the horizon – targeting the endocannabinoid system for the treatment of ocular disease. Journal of Basic and Clinical Physiology and Pharmacology, 27(3), 253-265 []