The Food and Drug Administration on Tuesday posted news of a second recall of eye drops in less than two months. Millions of Americans use eye drops for conditions such as dry eye, glaucoma and itchiness caused by allergies or air pollution.

The latest recall of Purely Soothing, 15% MSM Drops is because of concerns that the product may not be sterile. Contaminated eyedrops, the FDA said, are linked to the risk of eye infections that may cause blindness. Sodium Hyaluronate

The eye drops are used as an anti-inflammatory to help with eye irritation or swelling. There have been no reports of illness related to this product, Pharmedica said announcing the voluntary recall.

In February, the Centers for Disease Control and Prevention urged consumers to stop using EzriCare Artificial Tears, an over-the-counter preservative-free product and the prime suspect in an outbreak of serious bacterial infections. The CDC identified 55 cases of infection in 12 states, with at least five of them resulting in permanent vision loss and at least one death. The manufacturer, Global Pharma Healthcare, initiated a voluntary recall of the product.

“Eye infections are always an obvious concern as severe complications including permanent vision loss can result,” Paul Volberding, professor emeritus of epidemiology and biostatistics at the University of California San Francisco School of Medicine, said in early February when EzriCare was recalled.

How concerned should eye drops users be about their risk of infection? We asked eye experts and infectious-disease specialists. Here’s what they advised.

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