Why Is the FDA Requiring a Vision Warning on Weight-Loss Drugs?
The US Food and Drug Administration (FDA) has ordered a new safety warning for all glucagon-like peptide-1 (GLP-1) receptor agonist drugs, a class of medicines widely used to treat obesity, type 2 diabetes and other health conditions. The category includes Novo Nordisk's Ozempic and Wegovy, as well as Eli Lilly's Mounjaro and Zepbound.
The warning concerns non-arteritic anterior ischemic optic neuropathy (NAION), a rare eye condition caused by reduced blood flow to the optic nerve. It can lead to sudden vision impairment and, in some cases, permanent loss of sight.
How High Is the Risk of NAION?
The FDA began examining the potential risk after a 2024 medical study suggested a possible link between semaglutide — the active ingredient in Ozempic and Wegovy — and the eye disorder. A review of more than 125 clinical trials found that:
- NAION occurred in approximately six out of every 100,000 patients who used a GLP-1 medicine for at least a year;
- The corresponding rate among patients receiving a placebo or other glucose-lowering treatments was fewer than four cases per 100,000 people.
The regulator also identified reports of the condition through its adverse event reporting system, which monitors suspected drug-related side effects and injuries. The FDA described NAION as rare but worth watching for.
Which Symptoms Require Immediate Medical Attention?
The FDA advised patients and healthcare providers to remain alert to possible symptoms, including:
- Blurred vision
- Blind spots
- Colour distortions
- Other visual disturbances
Patients experiencing sudden changes in vision should seek medical attention immediately, the regulator said.
Growing Scrutiny of Weight-Loss Medicines
The new warning comes amid growing regulatory scrutiny of GLP-1 medicines, which have seen surging global demand because of their effectiveness in managing diabetes and promoting weight loss. For people with diabetes or those considering these drugs for weight loss, understanding this rare but serious risk — and staying in close contact with a doctor — is essential.
Tracking Your Health Day to Day
Beyond watching for vision changes, patients on GLP-1 medicines should keep an eye on trends in blood sugar, weight and blood pressure. With the Xiaoshu Health App, you can sync Apple Health data to track relevant metrics, helping you and your doctor better assess your health during treatment.