The joke about "needing longer arms" when you grow older and try to read small print is common enough.
The cause – a natural decline in our eyes' ability to focus on nearby objects, or presbyopia – is the reason so many people end up getting reading glasses in older age.
Now, for the first time, there could be another solution on hand.
In October, the US Food and Drug Administration (FDA) granted regulatory approval to the first eye drops that treat presbyopia – a product called Vuity, developed by the company Allergan.
Now, these drops have been made available on prescription, and they could mean millions of people can ditch their reading glasses, at least some of the time.
In presbyopia, the lens of the eye gets harder and less elastic with age, and the eye muscles lose power over time. Thus, it becomes more difficult to focus on things that are close up, especially when they're small.
"Many Americans deal with presbyopia, which typically begins around age 40, by relying on reading glasses or resorting to work-arounds like zooming in on their digital devices to see up close," says optometrist Selina McGee, from the American Academy of Optometry.
So, how can eye drops help with this? Vuity is formulated with 1.25 percent pilocarpine, a medication that belongs to the class of miotics – drugs that shrink the pupil of the eye. These medications are used to reduce pressure in the eye and in some diagnostic procedures.
As pilocarpine shrinks the pupil, the eye is better able to focus, improving vision in the near range, while distance vision is unaffected. Once the treatment has been approved by an eye doctor, the drops are simple and safe to apply: they can have an effect in as little as 15 minutes, and can continue working for up to six hours.
Pilocarpine isn't without its risks. The drug has been around for a while, and is on the World Health Organization's list of essential medicines, so we have a decent idea about its safety profile; adverse side effects include the very rare risk of retinal detachment and it should also not be used if the person has inflammation of the iris.
Additionally, because the eye drops shrink one's pupils, they naturally affect a person's low-light vision, so there are also warnings about driving at night or doing anything else dangerous in poor lighting.
Two phase 3 clinical trials – yet to be published in a peer-reviewed journal – involving 750 participants in total were used to test Vuity compared to a placebo drop, with the treatment showing a statistically significant improvement in vision in volunteers.
No serious side effects were reported, although 14.9 percent of people reported mild headaches, and up to 5 percent of participants reported other side effects, such as "eye redness, blurred vision, eye pain, visual impairment, eye irritation and an increased production of tears," according to The New York Times.
"There are many kinds of this medicine in trials, but this is the first to be approved," ophthalmologist Ella Faktorovich, from the Pacific Vision Institute, told ABC7 News. "It is pretty remarkable."
A month's supply of Vuity costs around US$80, and it has been shown to work best in people aged between 40 and 55 with mild or moderate presbyopia; it's likely that older people won't get as much help from the eye drops, and a prescription doesn't mean you can toss your reading glasses in the bin, but it's still a hugely welcome development.
Furthermore, this is just the very first step. While Vuity has snagged the first FDA approval, there is a slew of other presbyopia eye drops in the works already.
Some of them, like MicroLine by Eyenovia and CSF-1 by Orasis, also use pilocarpine, but others are going for different active ingredients altogether, or combine it with something else, to try for smaller doses, fewer side effects, and better overall safety profiles.
It seems like it's just a matter of time until more drugs follow Vuity onto the market, so watch this space – perhaps with glasses perched on your nose.