Product information for semaglutide has been updated by the Medicines and Healthcare products Regulatory Agency (MHRA) to warn healthcare professionals and patients about the “very rare risk” of users losing their vision.
Updated yesterday, the guidance now contains information about “the risk of the very rare occurrence of non-arteritic anterior ischemic optic neuropathy (NAION)” in patients taking semaglutide.
Read more: Safety warnings for GLP-1s strengthened by MHRA
According to the MHRA, the condition occurs “due to reduced blood flow to the front portion of the optic nerve, which typically causes sudden, painless vision loss in one eye”.
And patients who have experience NAION describe it as a “blurring or cloudiness of vision”, it added.
Patients taking semaglutide, the active ingredient in Wegovy, who notice a change in their eyesight, such as “sudden impairment” of vision, should “urgently attend” eye casualty or A&E, the medicines regulator urged.
Be alert
MHRA chief safety officer Dr Alison Cave said that “patient safety is the MHRA’s top priority and we continually monitor the safety and efficacy of all licensed medicines”.
“While the potential risk of NAION for patients prescribed semaglutide is extremely small, it is important that patients and healthcare professionals are alert to the associated symptoms,” she stressed.
Read more: ‘Eye stroke’ in one of 4,400 lawsuits filed against GLP-1 manufacturers
It comes after the MHRA strengthened product information for all GLP-1s at the end of last month to highlight the “small risk of severe acute pancreatitis” and “rare reports of necrotising and fatal pancreatitis”.
The medicines regulator said that while GLP-1s are “generally considered safe and effective for their authorised uses”, like all medications “they are not without risk”.
Read more: ‘Risky dosing hacks’ increase as weight loss jab prices rise
Meanwhile, an American news publication reported last week that thousands of GLP-1 users claim manufacturers didn’t sufficiently warn them of the potential side effects of taking the weight loss drugs.
It revealed that one man suffered an “eye stroke” in both eyes, leaving him blind, while a woman suffered severe vomiting before later being diagnosed with a brain dysfunction disorder.

