According to data cited in the journal Eye and Visionmyopia affects around 34% of the world’s population, with already nearly one in three people in some rich countries. Faced with this predicted wave, researchers are testing new levers to better control the disease, including in adults, who have long been left aside. An American team has just shown that a single drop of a low-dose eye drop, already used in children, is enough to modify vision and certain internal parameters of the eye for at least 24 hours in young myopic adults.
This eye drop is a low dose atropine (0.01% to 0.1%), studied by Lisa Ostrin and Barsha Lal at the College of Optometry atUniversity of Houston and described in the journal Eye and Vision. A single instillation resulted in lasting changes in pupil size and focusing ability, without altering the structure of the eye, with only a transient change in retinal blood flow.
How low-dose atropine works for 24 hours in adults
Low-dose atropine is often used to slow the progression of myopia in children, but its immediate impacts on the retina and choroid are not yet well understood. Ostrin’s recent research examined the short-term effects of various concentrations of low-dose atropine on the length of the eye, retinal blood vessels, and the thickness of the retina and choroid, which lies just behind the retina. These parameters are crucial because an increase in eye length is linked to myopia and, as the eye lengthens, the retina and choroid experience stretching.
In this randomized, double-blind study, 20 young adults with an average age of 25.5 years and myopia of −1.9 diopters received, during 5 spaced sessions, a drop in the right eye: either a placebo or atropine at 0.01%, 0.025%, 0.05% or 0.1%. The researchers then examined the structure of the eye, the thickness and length of the central retina one hour and 24 hours later.
“These results indicate that a single instillation of atropine does not alter axial length or retinal or choroidal thickness over 24 hours but may transiently affect superficial retinal perfusion in a time-dependent manner.“explained Lisa Ostrin in the University of Houston press release and in Eye and Vision.
The results show the absence of significant modification in axial length or retinal and choroidal thickness, whatever the concentration tested. On the other hand, the perfusion of the superficial vascular plexus of the retina decreased slightly at one hour, before returning to normal at 24 hours.
“Controlling” myopia over 24 hours: what it really means
Press releases from the University of Houston point out that myopia affects approximately one third of American adults. However, Lisa Ostrin’s work does not observe a reduction in myopia in one day: it follows indicators such as the pupil, accommodation or retinal perfusion, which are possible links in the chain leading to the elongation of the eye.
Of the low dose atropine drops could slow the progression of childhood myopia by approximately 30 to 60% depending on the concentration. In Europe, the European Commission approved in June 2025 a 0.01% atropine eye drop called
Ryjuneathe first medication indicated to slow the progression of myopia in children. Major research involving 852 children aged three to 14, with myopia ranging from -0.5 to -6.0 diopters, found that Ryjunea slowed the progression of myopia over a two-year period. For children whose myopia increased by at least 0.5 diopters per year, those treated with the approved dose of Ryjunea saw their myopia worsen by 0.34 diopters, compared to 0.54 diopters for those who received placebo eye drops (eye drops without active ingredient).
The study in adults suggests that these same mechanisms are activated from the first drop, with functional and vascular effects that extend over 24 hours without visible structural alteration. But nothing has yet been approved specifically for adults, in whom any use must be discussed with an ophthalmologist.