Contact lenses that release medicine may help fight glaucoma

By Laura Mize • Published: March 7th, 2014
Category: Health in a Heartbeat

If you think about it, contact lenses are pretty amazing things: tiny, fragile, curved pieces of film, made to fit your eyes and your exact vision prescription.

They’re fragile enough that you could rip them in half, but effective enough to help you see the world clearly.

Scientists from Boston are working to make contacts that do even more. Their goal is to develop lenses that dispense medication for people with glaucoma. According to the World Health Organization, Glaucoma is one of the two most common causes of blindness. It is treatable, but not reversible. The disease damages sight by harming the optic nerve. Once vision is reduced due to glaucoma, there’s no getting it back. That’s why treatment is so important.

Glaucoma has a few different causes, but most cases result from increased pressure in the eyeball. The most commonly prescribed glaucoma medication, called latanoprost [lah-TAN-oh-prahst], helps reduce the pressure. It is used mostly in eye-drop form, which is problematic for many patients. A 2008 study, for example, showed that less than 10 percent of this medication dispensed via eye drops is actually absorbed into the eyes.

That’s where the contact lenses would come in handy. Writing in the journal Biomaterials, the Boston researchers describe their tests of latanoprost-laced lenses on rabbits. The trials showed the lenses emitted drugs for the desired 28 days.

In the world of drug delivery, that’s a significant achievement. Other groups had previously tried to develop lenses that continuously emit medication for various purposes, but failed.

But there’s still more work to do. The latanoprost lenses must continue to go through testing, including trials in humans, before we know whether they work as hoped. If they do, these new contacts would be a simple solution to a serious problem.