“Purpose: Glaucoma is a leading cause of irreversible blindness globally, primarily driven by elevated intraocular pressure (IOP). Still, some patients progress despite significant IOP lowering, potentially due to impaired ocular blood flow. This study aimed to evaluate the effects of dronabinol, a synthetic tetrahydrocannabinol derivative, on ocular blood flow in primary open-angle glaucoma (POAG) patients.
Methods: This randomized, double-masked, placebo-controlled, cross-over study included 23 patients with treated POAG (mean age 68 ± 7 years). All participants received dronabinol (11 patients received 5 mg and 12 received 10 mg in a randomized fashion) on one study day and placebo on the other study day. The primary outcome was optic nerve head blood flow (ONHBF) measured by laser speckle flowgraphy. Mean blur rate was determined for the large vessel area (MV), the tissue area (MT) and the total ONH area (MA). Secondary outcomes included vessel densities assessed by optical coherence tomography angiography, IOP, and blood pressure.
Results: Administration of 10 mg dronabinol significantly increased ONHBF (MA: 10.8 ± 20.6%, p = 0.018, MV: 12.0 ± 24.8%, p = 0.042, and MT: 11.0 ± 22.6%, p = 0.022, each vs. placebo) up to 4 h post-administration without affecting IOP or mean arterial pressure (p > 0.548 each). Additionally, a significant increase in vessel density in the superficial vascular plexus was found after administration of 10 mg dronabinol (6.7 ± 14.7%, p = 0.040 vs. 5 mg).
Conclusion: This pilot study demonstrates that systemic dronabinol enhances ONHBF in glaucoma patients, suggesting its potential as adjunct therapy for glaucoma by targeting vascular dysfunction. Further longitudinal studies are needed to explore its long-term impact on disease progression and visual field preservation.”
https://pubmed.ncbi.nlm.nih.gov/40772417/
“Tetrahydrocannabinol (THC) has long been considered a treatment option for glaucoma, mainly because of its IOP-lowering properties. In addition, THC may also increase ocular blood flow, at least in healthy subjects. Recent data from our laboratory confirm that even low doses of THC, which neither affect IOP nor induce systemic psychoactive side effects, can increase ocular blood flow considerably.”
“In summary, our study demonstrates that administration of 10 mg dronabinol leads to a significant increase in ocular blood flow in patients with glaucoma. The effect seems to be dose-dependent, as a single administration of 5 mg had no effect on ocular blood flow. These findings highlight the potential role of dronabinol in improving ocular perfusion in glaucoma patients but also underscore the importance of considering age and disease-related factors when assessing cannabinoid-mediated vascular effects. Further investigations with larger sample sizes, longer study durations, and multiple applications instead of single intake are warranted to evaluate the potential clinical benefits of this therapeutic approach.”