Study warns CBD may increase eye pressure in glaucoma patients

A new study warns that cannabidiol (CBD), a major compound in marijuana, may cause an increase in eye pressure. This is bad news for glaucoma patients currently taking medical marijuana and highlights the need to further study this potential complication. The opposite effect was associated with the other major compound in cannabis, THC, though its positive effect was eliminated when taken with CBD.

CBD is a promising compound in cannabis that may provide a variety of medicinal effects, but as with many things, there's the potential for complications. A new study out of Indiana University found that CBD increased eye pressure in lab rats for four hours after it was administered.

An 18-percent increase in eye pressure was found in lab rats four hours after they were given CBD. In contrast, rats given THC experienced substantial decreases in eye pressure four hours after administration: 22-percent for male rats and 17-percent for female rats.

Though one may speculate that consuming both together would neutralize the pressure, that wasn't the case. The study found that when CBD and THC were administered at the same time, the THC's pressure-reducing effects were blocked.

Talking about the findings was study lead Alex Straiker, who said:

This difference between males and females — and the fact that CBD seems to worsen eye pressure, the primary risk factor for glaucoma — are both important aspects of this study. It's also notable that CBD appears to actively oppose the beneficial effects of THC.