GLP-1 drugs under investigation after rare sudden vision loss reports

Technology Sep 25, 2026

GLP-1 drugs, which are popular for treating diabetes and obesity, are now being investigated after reports of sudden vision loss in some users.

The European Medicines Agency says this side effect is very rare, about up to one in 10,000 people on semaglutide might be affected.

Some studies hint the risk could be higher for adults with type 2 diabetes taking semaglutide.

Conflicting NAION evidence triggers 216 actions

Novo Nordisk's own trials did not find an increased risk of NAION, but recent observational studies and a big 2026 analysis suggest otherwise.

This has led to 216 pending actions against Novo Nordisk and Eli Lilly, focusing on how these drugs were tested and approved.

Regulators are keeping a close eye as both companies defend their products in court.