The U.S. Food and Drug Administration is requiring new safety warnings on all GLP-1 drugs after finding evidence of a potential increased risk of a rare eye condition, the agency said on Monday.

The condition, which can cause sudden vision loss, known as nonarteritic anterior ischemic optic neuropathy (NAION), is rare, and a causal relationship has not been established.

The FDA is requiring the makers of all GLP-1 medications to add a warning about the potential increased risk of NAION associated with use of these medications, it said.

NAION is a condition that can result in sudden decreased vision, including permanent vision loss.…