Weight loss medications under scrutiny: Can Ozempic and Wegovy cause blindness?

As these GLP-1 receptor agonists grow in popularity for both diabetes management and weight loss, researchers and medical professionals are closely monitoring their potential side effects. A series of recent studies have suggested a possible association between semaglutide and NAION, prompting further investigation into the safety profile of these widely used medications.

Novo Nordisk’s position on NAION risk

A Kazinform correspondent recently reached out to Novo Nordisk, the pharmaceutical company behind Ozempic, Rybelsus, and Wegovy, with inquiries about the potential link between semaglutide and vision-related side effects, particularly NAION. In an exclusive response to Kazinform, Novo Nordisk addressed these concerns and provided insight into their internal safety assessments and external research findings.

According to their findings, NAION is a very rare eye disease and is not listed as an adverse reaction in the approved package leaflets for semaglutide-based medications.

“After a thorough evaluation of studies conducted by the University of Southern Denmark, as well as our own internal safety reviews, we believe there is no change in the risk profile of semaglutide,” Novo Nordisk stated.

While studies have shown a doubling of the relative risk of NAION, the absolute risk remains extremely low. One study indicated that 2 out of every 10,000 people treated with semaglutide in a year developed NAION, compared to 1 in 10,000 in the non-semaglutide group. These results suggest that, despite the relative increase, the actual number of affected individuals remains minimal. Furthermore, no causal relationship has been established between semaglutide treatment and the development of NAION.

“Our internal safety analysis and randomized controlled clinical trials, which included a blinded ophthalmologist review, have identified very few ophthalmologist-confirmed cases of NAION. Based on this, we see no increased risk associated with our GLP-1 medications,” Novo Nordisk affirmed.

Growing scientific inquiry and studies

This response comes amid growing concerns about potential side effects of GLP-1 agonists, which are widely used for weight loss and diabetes management. Recent research, including a study published in JAMA Ophthalmology in July 2024, suggested a possible link between semaglutide and NAION. Another investigative review in the same journal highlighted nine cases of patients experiencing vision issues while on semaglutide or tirzepatide. Among these cases, seven individuals developed NAION, one experienced a retinal stroke, and another had swelling in both optic nerves, though they did not lose vision.

Dr. Bradley Katz, an ophthalmologist at the John A. Moran Eye Center and lead author of the study, stressed the importance of ongoing research into the effects of GLP-1 medications.

“Because so many people are using these medications, it’s critical to monitor any ill effects on the eye or other parts of the body,” he stated.

In 2023, 2-3% of the U.S. population received a prescription for one of these medications, underscoring the need for continued safety monitoring.

Semaglutide works by stimulating insulin release from the pancreas, helping to regulate blood sugar levels. In addition to diabetes management, it suppresses appetite and slows digestion, contributing to weight loss when combined with a healthy diet and exercise. However, as with any medication, potential risks must be weighed against the benefits in consultation with a healthcare provider.

Novo Nordisk reiterated that patient safety remains their top priority. “We take all reports of adverse effects seriously, including those related to eye diseases. These conditions are well-known complications for individuals with diabetes, and any concerns about starting semaglutide treatment should be discussed with a physician,” the company concluded.

Alternative weight loss methods

Beyond GLP-1 receptor agonists, people use various approaches to achieve weight loss. Common methods include dietary adjustments such as calorie restriction, intermittent fasting, and low-carb diets. Regular exercise, including strength training and cardio workouts, plays a crucial role in weight management. Some individuals opt for prescription weight-loss medications or undergo bariatric surgery for more significant interventions. Behavioral therapy and lifestyle coaching also help individuals develop healthier habits.

Additionally, non-prescription supplements and medical devices like gastric balloons provide alternative options, though their effectiveness varies. Choosing the right weight loss strategy should be based on individual health needs and guided by medical professionals.

Earlier, it was reported that South Korea’s health ministry announced a ban on remote prescribing of weight loss medications, including Wegovy, which was released in the country in October 2024, to prevent potential abuse.