Patients prescribed semaglutide, marketed as Ozempic and Wegovy, for weight loss may face a higher risk of developing a rare but serious eye condition, a new study indicates.
Researchers from Harvard Medical School analyzed data from 17,000 patients over six years, finding that those taking semaglutide for type 2 diabetes were four times more likely to be diagnosed with non-arteritic anterior ischemic optic neuropathy (NAION) compared to those not on the drug. Among patients taking semaglutide for obesity, the risk was seven times higher. Despite these findings, the study does not confirm that semaglutide causes the condition or explain the differing risks between groups. The overall number of affected patients remains small.
Increased Risks Highlighted
NAION, a condition that can lead to vision loss in one eye, is caused by reduced blood flow to the optic nerve and currently has no treatment. The condition affects up to 10 out of every 100,000 people in the general population.
The study revealed:
- 17 cases of NAION among type 2 diabetes patients taking semaglutide.
- 6 cases among type 2 diabetes patients on other medications.
- 20 cases among overweight and obese patients taking semaglutide.
- 3 cases among overweight and obese patients on different drugs.
Professor Joseph Rizzo, an ophthalmology expert from Harvard Medical School, emphasized the significance of the findings but noted the need for further research involving a larger and more diverse population.
Industry Response and Concerns
Novo Nordisk, the manufacturer of semaglutide, acknowledged patient safety as a priority but pointed out several limitations in the study. They highlighted that factors like smoking status and the duration of diabetes were not considered. The company also noted the difficulty in accurately coding and identifying cases of NAION.
Despite the hype surrounding semaglutide, especially after endorsements by celebrities on social media, concerns have arisen about its misuse. Online pharmacies have been selling semaglutide injections with minimal checks on buyers’ weight or health status, prompting health authorities to warn against using the drug as a “quick fix” for weight loss.
Potential Side Effects and Benefits
All medications carry potential side effects, and semaglutide is no exception. Common side effects include nausea, vomiting, diarrhea, stomach pain, and constipation. Both Ozempic and Wegovy list a change in vision as a more serious potential side effect.
Given the rapid increase in semaglutide use and its potential approval for treating conditions beyond obesity and type 2 diabetes, experts like Professor Graham McGeown from Queen’s University Belfast stress the importance of further study. He emphasized the need to balance possible drug side effects against their likely benefits.
Ongoing Research
Novo Nordisk is currently conducting a trial called Focus, which will conclude in 2027, to assess the long-term effects of semaglutide on diabetic retinopathy, another eye condition affecting type 2 diabetes patients.
In the meantime, UK eye experts from the Royal College of Ophthalmologists recommend that patients taking semaglutide be informed of the small risk of developing eye diseases.
Conclusion
While the study’s findings are significant, they are tentative and require further investigation. Patients should consult with healthcare providers to understand the risks and benefits of semaglutide, ensuring informed decisions about their treatment options.