Comparative adverse-event reporting patterns of semaglutide and tirzepatide: a disproportionality analysis of FAERS
- Design
- Pharmacovigilance · 215337 participants · Mixed outcome
- Match to healthy normal-weight adults aged 55–75
- Population unclearUNKNOWN: the analysis counts spontaneous reports and gives no age, BMI or diabetes data for the people behind them.
- Could weight loss explain it?
- PossiblyNo weight change, HbA1c or mediation analysis is reported, so the reported differences cannot be separated from weight and metabolic change; both drugs compared lower weight, which further confounds the contrast.
- Study tier
- Study tier 4VERY_LOW: a single disproportionality analysis of spontaneous reports, which the model places at its lowest tier, and whose authors state the findings reflect reporting patterns rather than comparative clinical risk or causality.
- Assessment
- Version 2 · Two independent AI reviews agreed · Nov 6, 2026
Study facts come from the paper. Population match, weight-loss explanation and study tier are our judgments, made against the reference group of healthy normal-weight adults aged 55–75.
This study compared spontaneous adverse-event reports for semaglutide and tirzepatide in the US FDA reporting system from January 2022 through June 2026, using 215,337 deduplicated reports, of which 60,423 named semaglutide only and 143,126 tirzepatide only. Semaglutide reports more often described impaired gastric emptying (reporting odds ratio 6.39), intestinal obstruction or ileus (4.56), acute kidney injury (2.51), pancreatitis (2.18), vomiting (2.11), optic ischaemic neuropathy (15.77), hospitalization (adjusted odds ratio 2.80) and death (1.21), while alopecia was reported relatively more often with tirzepatide (0.74). An exploratory male-only analysis found erectile dysfunction in 92 of 16,673 semaglutide reports against 46 of 27,321 tirzepatide reports (3.29, 95% CI 2.31-4.69). The authors state these are reporting patterns, not comparative clinical risk or causality.
01Findings
What the study reported
- Drugs
- Semaglutide, Tirzepatide
- Comparator
- tirzepatide (semaglutide reports compared with tirzepatide reports)
- Primary outcome
- reporting odds for gastrointestinal, renal and ocular events, alopecia, serious outcomes, mortality and reporting chronology
- Effect
- Semaglutide versus tirzepatide: impaired gastric emptying ROR 6.39, intestinal obstruction/ileus 4.56, acute kidney injury 2.51, pancreatitis 2.18, vomiting 2.11, optic ischaemic neuropathy 15.77, hospitalization aOR 2.80 and death aOR 1.21; alopecia was reported relatively more often with tirzepatide (ROR 0.74); exploratory male-only erectile dysfunction ROR 3.29 (95% CI 2.31-4.69)
- 95% confidence interval
- 95% CI 2.31-4.69 (erectile dysfunction ROR 3.29, exploratory)
- P value
- q < 0.001 (erectile dysfunction, false discovery rate adjusted)
- Follow-up
- Not stated
- Adverse events
- Semaglutide reports showed higher reporting odds than tirzepatide for impaired gastric emptying (ROR 6.39), intestinal obstruction/ileus (4.56), acute kidney injury (2.51), pancreatitis (2.18), vomiting (2.11), optic ischaemic neuropathy (15.77), hospitalization (aOR 2.80) and death (aOR 1.21); alopecia was reported relatively more often with tirzepatide (ROR 0.74)
- Limitations
- Spontaneous reporting data cannot give incidence or causality, as the authors state; a comparison of reporting between two drugs is shaped by differential reporting and by how long each has been on the market, no characteristics of the people behind the reports are available, and the erectile-dysfunction finding is explicitly exploratory.
Who was studied
- Obesity status
- not reported in abstract
- Diabetes status
- not reported in abstract
- Cvd status
- not reported in abstract
- Ckd status
- not reported in abstract
- Baseline condition
- not reported in abstract
- Sample size
- 215337
- Inclusion exclusion
- FAERS reports submitted January 2022 through June 2026; after deduplication, predefined exposure criteria selected semaglutide-only, tirzepatide-only and both-drug reports without additional suspect active ingredients
Study quality details
- Study design
- Pharmacovigilance analysis
- Sample size
- 215337
- Randomization
- no
- Blinding
- n/a
- Comparator
- tirzepatide (semaglutide reports compared with tirzepatide reports)
- Follow up duration
- not stated
- Outcome type
- mixed
- Replication
- not assessed
- Consistency with other evidence
- not assessed
- Population applicability
- UNKNOWN
- Statistical precision
- reporting odds ratios with 95% confidence intervals and false discovery rate adjustment; the abstract prints an interval only for the exploratory erectile-dysfunction result; 60,423 semaglutide-only and 143,126 tirzepatide-only reports
- Risk of bias
- not assessed
- Peer review status
- yes
02Funding
Funding and conflicts
- Funding
- not reported in abstract
- Industry funded
- Unclear
- Manufacturer
- not stated in source
- Sponsor role
- not reported in abstract
- Author conflicts
- The authors declare no competing interests.
- Independent replication
- unknown
Funding is shown on every study and never used to score it.
04Source
The source, as retrieved
Abstract
[BACKGROUND] Semaglutide and tirzepatide are widely used for type 2 diabetes and obesity, but comparative post-marketing safety data remain limited. [OBJECTIVE] To compare adverse-event reporting patterns for semaglutide and tirzepatide in the FDA Adverse Event Reporting System (FAERS), focusing on gastrointestinal, renal and ocular events, alopecia, serious outcomes, mortality, and reporting chronology. [METHODS] This retrospective pharmacovigilance study analyzed FAERS reports submitted from January 2022 through June 2026. After deduplication, 215,337 unique reports remained; predefined exposure criteria identified 60,423 semaglutide-only reports, 143,126 tirzepatide-only reports, and 853 reports listing both drugs without additional suspect active ingredients. Disproportionality was assessed using reporting odds ratios (RORs) with 95% confidence intervals. Multivariable logistic regression, false discovery rate adjustment, and reporting-latency analyses were also performed. [RESULTS] Semaglutide showed higher reporting odds than tirzepatide for impaired gastric emptying (ROR 6.39), intestinal obstruction/ileus (ROR 4.56), acute kidney injury (ROR 2.51), pancreatitis (ROR 2.18), vomiting (ROR 2.11), and optic ischaemic neuropathy (ROR 15.77). Alopecia was relatively more frequently reported with tirzepatide (ROR 0.74). Semaglutide reports had higher adjusted reporting odds of hospitalization (aOR 2.80) and death (aOR 1.21). In an exploratory analysis restricted to male reports, erectile dysfunction was reported in 92 of 16,673 semaglutide reports and 46 of 27,321 tirzepatide reports (ROR 3.29, 95% CI 2.31-4.69; q < 0.001). [CONCLUSIONS] Semaglutide and tirzepatide exhibited distinct post-marketing reporting patterns. The erectile-dysfunction finding was exploratory and hypothesis-generating. All findings reflect spontaneous reporting rather than comparative clinical risk or causality and require confirmation in population-based studies.
Where this record came from
| Source | Retrieved | Identifier |
|---|---|---|
| pubmed | Nov 1, 2026 | 42955519 first ingestion |
| pubmed | Nov 1, 2026 | 42955519 duplicate matched on doi |
| owner-review | Nov 6, 2026 | reviewed_by set to Carrie Schluter (2026-11-05) on the owner's own confirmation. The assessment is unchanged and still the auto-classifier's, so its extracted values stay withheld under the 2026-10-18 decision. |
| pubmed | Nov 8, 2026 | 42955519 duplicate matched on doi |
| pubmed | Nov 8, 2026 | 42955519 duplicate matched on doi |