Guideline / position statementindependent cross-checkfull text checked★ key study I-ODD-120 in-depth review
EU regulator: optic nerve stroke is a very rare semaglutide side effect
PRAC concludes eye condition NAION is a very rare side effect of semaglutide medicines Ozempic, Rybelsus and Wegovy (EMA news, 6 June 2025)
Overview
European Medicines Agency (PRAC). EMA website 2025
About 1 extra case per 10,000 person-years; product information updated.
Does the study support the specific claim? Partly · Methodological quality: moderate
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Assess NAION with semaglutide.
- How was the study done?
Regulatory review of all data.
- How many people, animals or samples were studied?
Not applicable.
- What was actually found?
Very rare side effect, about two-fold relative risk.
- How large was the observed effect?
About +1 per 10,000 person-years.
- What do the results mean in everyday life?
Seek urgent care for sudden vision loss; the risk is very low.
- What are the study's limitations?
Summary statement.
- What does it say about Elawady's specific claim?
Supports a real association with very low absolute risk.
- Do the results apply to Germany and Europe?
Direct.
- What can explicitly not be concluded from this study?
Mechanism.
Scientific in-depth review
1. Full reference
- Authors
- European Medicines Agency (PRAC)
- Journal
- EMA website
- Year
- 2025
- Identifier
- Verification
- verified – Web page fetched 2026-10-26
- Retracted
- no
- Corrections
Announcement revised 13 June 2025 to delete a reference to a European Commission legally binding decision
- Extent checked
- full text
- Conflicts of interest and funding
Regulatory agency.
2. Research question
Is NAION a side effect of semaglutide?
3. Study design and population
- Study design
- Guideline / position statement – Regulatory safety review (PRAC) of non-clinical, clinical-trial, post-marketing and literature data
- Population
Users of semaglutide (Ozempic, Rybelsus, Wegovy)
- Country
EU
- Period
Review concluded June 2025
- Sample size
Not applicable
- Inclusion and exclusion criteria
Not applicable
4. Methods and endpoints
- Exposure / intervention
Semaglutide
- Comparator
Non-users
- Endpoints
NAION
- Statistical methods
Not applicable
5. Actual results
- Results
NAION is a very rare side effect of semaglutide (up to 1 in 10,000 people). Several large epidemiological studies suggest about a two-fold increase in type 2 diabetes, about one additional case per 10,000 person-years; clinical trials point to a slightly higher risk. Product information updated; stop semaglutide if NAION is confirmed.
- Absolute risks
About 1 additional case per 10,000 person-years.
- Authors' conclusion
NAION added to product information as a very rare side effect.
6. Strengths
- Comprehensive regulatory data access
7. Weaknesses
- Not a peer-reviewed analysis; methods summarised only
8. Risk of bias
- Orienting tool
- none applicable
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- not assessable
- Rationale
Regulatory statement.
9. Assessment of the statistical interpretation
Consistent with Simonsen 2025 absolute excess (stats/C-ODD-10.py).
10. Relevance to the specific claim
Authoritative EU position: the association is accepted as a very rare side effect, which supports the existence of the risk but contradicts 'markedly higher' in absolute terms.
11. Independent contrary findings
RCT meta-analyses not significant (I-ODD-119).
12. Transferability to Germany and Europe
Direct (EU).
13. Overall methodological judgement
Accepts a causal-enough signal for labelling; absolute risk very low.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | moderate |
| Risk of bias | not assessable |
| Precision of results | not applicable |
| Directness | direct |
| Reproducibility | not replicated |
| Consistency with the overall evidence | consistent |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |
14. Open questions
Mechanism.