Some signs of passing time are clear — others get blurry, like the screens David Bonnett spends his day with from his home office in Chesterfield.

“Fortunately, I made it closer to 50 before I really started having issues. And it was mostly just reading. It was my smartphone and being able to read documents,” he said.

The rite of passage, the bulk pack of reading glasses.

“It’s like I’ve had a pair of those attached to my hip or to my neck, you know, every day, all day long,” he said, holding up the set that had been clipped to his collar.

For the past week or so, Bonnet has been trying Vuity, a newly FDA-approved, eyedrop designed to replace reading glasses. At around $80 per bottle, Bonnett figured it was worth a try.

“I’m not a paid spokesperson, absolutely not,” he laughed. “When I first put them in, drop in each, I closed my eyes for maybe a couple of minutes and voila. And it’s amazing. Things really are more clear, crisper.”

He is one of an estimated 128 million Americans living with presbyopia, an eye condition much more common than it is easy to say.

“Presbyopia is a word that just means old eyes in the Greek language,” explained ophthalmologist Dr. Jason Brinton. “When people get over age 40, the lens in their eye becomes stiffer and less flexible, and that means that it’s more difficult to read up close.”

He said the eyedrops are most successful at replacing eyeglasses for people aged 40 to 59.

“What Vuity allows is it uses the eyes’ natural focusing mechanism to decrease the pupil size and improve that depth of focus so that the eye can focus both far and near and see those without reading glasses.”

Beginning after about 15 minutes, the effects of the drops should last around six hours and can be used as part of a daily routine or for occasions when someone wants to go glasses-free. However, side effects can include headaches, redness, and eye pain — so they aren’t for everyone.

“People will need to visit their doctor and have a complete and thorough eye exam before being prescribed this,” said Dr. Brinton.

As pharmaceutical companies work on several new eyedrop-based ocular medications, Bonnett is looking forward to using Vuity for mostly weekend nights and activities. For days spent at the computer? He’s keeping his glasses nearby.

“If you can find a way to make things a little more convenient for you and your life, it seems like a really good product,” he said.

Dr. Jason P. Brinton is an internationally recognized specialist in the field of LASIK and refractive surgery. He is a graduate of Harvard College, earned his medical doctorate from the Harvard Medical School and is board certified by the American Board of Ophthalmology.