Glaucoma is a group of conditions that can lead to vision loss. It is often on the list of health problems that warrant medical marijuana treatment but there is not a lot of strong evidence backing that up. Studies looking into marijuana's ability to relieve eye pressure – a common characteristic of glaucoma – have been going on for decades, but more research is needed to give any definitive ruling on effectiveness. Plus, says Dr. J.H. Atkinson, there are plenty of alternative treatments now available for glaucoma.