The head of the nation’s only federally approved marijuana farm has revealed that he is developing cannabis eye drops to treat glaucoma.

In a podcast interview, pharmacologist Mahmoud ElSohly, director of the University of Mississippi’s Marijuana Research Project, discussed the history of how an eye doctor discovered that cannabis can relieve the interocular pressure associated with glaucoma. But while the THC in the plant treated the symptoms, it also means patients experience the high.

“The best way to treat glaucoma is not to take a drug that will affect your brain, affect your ability to function, the whole rest of your body just to lower the pressure inside the eyes,” ElSohly argued. “The way to do this is to develop, let’s say, eye drops, eye drops from marijuana.”

Both his lab and a separate, unnamed company that licensed the idea are looking into the eye drop possibility, with the company having already begun clinical trials, ElSohly said. It’s a notable advancement because THC is lipophilic, acting like an oil, and so “it doesn’t penetrate into the inner compartments of the eye to lower the pressure.”

“Therefore, only if you take systemically—meaning if you inhale it or swallow it or something—but then you deal with all the side effects of THC,” he said in the interview, which was recorded in February and published this month. “Now we’re developing a pharmaceutical product, and it’s been licensed by the way now, that we take the THC molecule and we modify it in a certain way to allow it to go inside the eye, and once inside, it breaks off and releases THC just in the eye to lower the pressure.”

“You don’t feel any psychological activity, it doesn’t even get into your blood. It’s all localized in the eye,” he said. “We have this product now that is being licensed and being developed as an eye drop.”

Listen to the conversation about the THC eye drops, which begins around 15:40, below:

“That’s the way to develop pharmaceuticals based on cannabis but not cannabis, based on marijuana but not marijuana,” he added during the appearance on the podcast of anti-legalization organization National Families In Action, for which ElSohly serves as a scientific advisory board member. “That’s the way to do it and develop the medicine.”

The targeted treatment of glaucoma using the novel delivery method that ElSohly described is noteworthy, but it also underscores the potential for the development of other valuable treatment options derived from marijuana that’s being inhibited under prohibition. One barrier that researchers and lawmakers alike have identified is the substandard quality of cannabis produced at ElSohly’s farm.

Currently, the University of Mississippi is the only federally approved source of research-grade marijuana, but scientists have complained about the cannabis supply, which one study found is genetically closer to hemp than products available in state-legal markets. That raises questions about the validity of studies that rely on the government’s marijuana.

The Drug Enforcement Administration said in September that it is taking steps to approve additional marijuana farms beyond ElSohly’s Mississippi operation, three years after the agency initially invited applications for such facilities.

In an earlier podcast segment released in September, ElSohly made a series of remarks that some viewed as reflective of a fundamental misunderstanding of marijuana issues.

The director characterized cannabis containing eight percent THC as “extremely high potency” and expressed confusion as to why individuals would seek out varieties in the commercial market that contain “20 percent or 15 or 18 or any of those high amounts.”

But ElSohly was thinking about marijuana consumption in the context of standardized clinical trials, where individuals would have to consume an entire joint in one sitting in order to compare the effects of a controlled dose with other subjects. Others have pointed out that consumers might prefer higher concentration products because they can achieve the desired effect without having to smoke as much.