GLP-1 Therapies Newsletter
Issue #28March 16, 20263 studies

Semaglutide linked to 74-fold higher risk of vision-threatening eye condition

The GLP-1 revolution continues to reshape medicine, but new research reveals some concerning side effects hiding in the data. This week's studies paint a complex picture of these blockbuster drugs.

👁️ Semaglutide Users Face Dramatically Higher Risk of Sudden Vision Loss

  • Analysis of over 30 million FDA adverse event reports found Wegovy (high-dose semaglutide) linked to 75 times higher odds of ischemic optic neuropathy compared to other drugs, while Ozempic showed 19 times higher odds

  • Men faced even greater risk than women, with 116 times higher odds in the analysis, and the vision-threatening condition can cause permanent blindness

  • The dose-dependent pattern suggests higher semaglutide doses may carry substantially greater eye risks, though the absolute risk remains low

Why it matters: This represents one of the strongest safety signals yet identified for GLP-1 drugs, potentially affecting millions of users who may be unaware of this rare but serious risk.

🎖️ Top 10% journal 🔗 The British journal of ophthalmology 🗓️ Mar 10

Key Findings

📊 Digital Nudges Boost Healthy Behaviors in GLP-1 Users

  • Simple digital prompts plus 2-minute videos increased expectations to adopt healthy behaviors by 0.30-0.77 standard deviations immediately after exposure in 5,054 GLP-1 users

  • Storytelling videos outperformed educational videos across 7 of 8 healthy behaviors, and effects persisted for 2 weeks

  • Participants receiving storytelling videos also reduced sugar-sweetened beverage consumption compared to controls

💡 Small digital interventions may help maximize the health benefits people get from expensive GLP-1 medications.
🥈 Top 2% journal 🔗 JAMA network open 🗓️ Mar 9

🔬 Tirzepatide Dominates Weight Loss Rankings

  • Meta-analysis of 21 trials involving 7,024 participants found 78.5% of people on GLP-1 drugs achieved weight loss versus just 26.5% on placebo

  • Tirzepatide ranked highest with 91.2% probability of being the most effective, followed by semaglutide at 85.4%

  • The drugs increased odds of weight loss by 11-fold compared to placebo across studies

💡 Head-to-head comparisons confirm tirzepatide as the most potent weight-loss medication currently available.
Top 50% journal 🔗 Medicine 🗓️ Mar 13

Implications

GLP-1 drugs continue proving their remarkable efficacy for weight loss and metabolic health, but emerging safety signals around vision loss highlight the need for careful patient monitoring and informed consent as these medications become mainstream treatments.

Studies in this issue

Primary sources used for this newsletter.

  1. How Common Hair Shedding Is and What Predicts It in People Using GLP-1 Medicines in Saudi Arabia
    main storySkin appendage disorders2026-03-09PMID 41799300
  2. Factors affecting patient preferences for weight-loss medications based on interviews, photo stories, and group talks
    key findingObesity pillars2026-03-12PMID 41815755
  3. Alcohol Use Disorder Outcomes with Metabolic Problems: Comparing GLP-1 Drugs and Approved AUD Medications
    key findingAlimentary pharmacology & therapeutics2026-03-11PMID 41813606

Continue reading

All GLP-1 Therapies issues