A University of Houston optometry researcher is warning against the use of low-level red light (LLRL) therapy as a method to control myopia, or nearsightedness, especially in children. Over the last few years, LLRL has emerged as a viable myopia treatment after studies reported the treatment as effective and responsible for significant reduction in myopia progression. The company behind one of the devices reports that it is already being used to address myopia in over 100,000 pediatric patients.

But the excitement over its results as a myopia treatment may have come too soon, ahead of its proven safety.

A new study shows that the therapy can put the retina at risk of photochemical and thermal damage. The study evaluated two different LLRL devices. Although both devices use Class I lasers, which are safe when viewed accidentally for brief periods of time, the study showed that longer use, as required for myopia treatment, may exceed safety limits for the eye.