SGLT2 inhibitors are associated with Fournier gangrene: the FDA identified 55 cases in six years versus only 19 with all other diabetes drugs over 35 years.
Original statement
وأن FDA رصدت 55 حالة غرغرينا فورنييه مع مثبطات SGLT-2 خلال ست سنوات مقابل 19 حالة فقط مع كل أدوية السكري الأخرى مجتمعة على مدى 35 عاماً.
verbatim according to source. Translation by the project; the Arabic wording is authoritative.
Translation
SGLT2 inhibitors are associated with Fournier gangrene: the FDA identified 55 cases in six years versus only 19 with all other diabetes drugs over 35 years.
Origin
- Source status
- Archive editors
- Attribution
- Archive editors (not Elawady)
- Origin
- https://eltayebat.com/rule/oral-diabetes-drugs/
- Attribution uncertainty
- Editorial narrative and study selection written by the archive operators.
- Claimed mechanism
Glucose in urine promotes genital infections.
- Claimed health effect
Fournier gangrene
- Population concerned
SGLT2 inhibitor users
- Geographic restriction by Elawady
none found
Scientific assessment
Potentially true – Some evidence points in favour of the statement, but it is not sufficient for a clear judgement.
Certainty of evidence: low – Further research is likely to change the assessment considerably.
1. What was claimed?
SGLT2 inhibitors cause Fournier gangrene.
2. What is demonstrably correct?
FDA: 55 cases with SGLT2 inhibitors (2013-2019) vs 19 with other agents (1984-2019); 3 deaths (A-ODD-12). Genital mycotic infections are a well-established, usually mild side effect (I-ODD-02). ADA 2026 lists Fournier gangrene as a rare adverse effect (I-ODD-16).
3. What is wrong or exaggerated?
The comparison of report counts over different periods is not a risk comparison: the authors list 'inability to establish causality or incidence', underreporting and confounding (A-ODD-12). The 84-RCT meta-analysis found MH-OR 0.41 (0.09-1.82) (I-ODD-12).
4. What remains unclear?
True incidence; probably very rare.
5. Which studies support it?
6. Which studies contradict it?
7. What applies to Germany and Europe?
EMA added a Fournier warning to SGLT2 inhibitor labels (not separately fetched; verified: false).
8. What is known about Egypt?
Egypt has one of the highest diabetes prevalences in the region; the same drug classes and insulins are used. Access barriers and cost may make advice to stop medication attractive, which increases the practical risk of this claim. No Egypt-specific evidence changes the assessment.
9. What practical conclusion is appropriate?
Pain, swelling or redness in the genital/perineal area with fever on SGLT2 inhibitors needs urgent care. The risk is rare and must be weighed against cardiorenal benefits.
Assessment details
- Rationale for certainty of evidence
Numbers correctly quoted from an FDA spontaneous-report case series, which cannot establish incidence or causality (authors' own limitation). A meta-analysis of 84 RCTs found no significant difference, but events were too few to exclude an increase. Labels carry a warning.
- Source quality
Archive editorial citing a pharmacovigilance case series.
- Regional transferability
Universal.
- Regional scope of the claim
- general (biological/medical)
- Last reviewed
- 26 October 2026 provisional
Scientific evidence in detail
Overinterpreted – A real finding exists, but the claim draws more from it than the data allow (e.g. association taken as cause, animal data applied to humans, small effect presented as large).
Research question: Are SGLT2 inhibitors associated with Fournier gangrene, and do the FDA case counts (55 in six years vs 19 in 35 years) indicate a higher risk?
Research question in detail (PECO)
- Population
- Users of glucose-lowering drugs
- Intervention or exposure
- SGLT2 inhibitors
- Comparison
- Other glucose-lowering drugs (DPP-4 inhibitors)
- Geographic scope
- universal biology
- Outcomes
- Fournier gangrene (hospitalisation)
Study results as reported by the authors. Our assessment follows below.
What speaks for the claim?
Fournier gangrene reports with SGLT2 drugs
Bersoff-Matcha SJ et al.. Ann Intern Med 2019 · PMID 31060053 · DOI 10.7326/M19-0085 Case series / case reportabstract checkedFDA spontaneous reports.
- Actual result
- 55 cases (2013-2019) vs 19 with other agents (1984-2019); 3 deaths.
- Methodological quality
- very low (spontaneous reports, no denominators)
- Relevance
- direct but cannot estimate risk
- Limitations
- Stimulated reporting; no incidence.
Fournier gangrene on SGLT2 drugs: very rare, any extra risk uncertain
Dave CV et al.. JAMA Intern Med 2019 · PMID 31479145 · DOI 10.1001/jamainternmed.2019.2813 Cohort studyfull text checkednewly addedCohort of about 500,000 men: higher point estimate, not significant.
- Actual result
- 15.0 vs 9.7 per 100,000 PY; aHR 1.73 (0.87-3.42).
- Methodological quality
- moderate
- Relevance
- direct
- Limitations
- 13 vs 24 events.
What speaks against the claim?
Fournier gangrene in SGLT2 trials
Silverii GA et al.. Diabetes Obes Metab 2020 · PMID 31637829 · DOI 10.1111/dom.13900 Meta-analysisabstract checkedMeta-analysis of 84 RCTs found no significant increase.
- Actual result
- MH-OR 0.41 (0.09-1.82).
- Methodological quality
- moderate (very few events)
- Relevance
- direct
- Limitations
- Underpowered.
What does the overall evidence say?
Editorial assessment based on the studies above – not itself a study result.
Which position is better supported?
Fournier gangrene is a very rare event (about 10-15 per 100,000 person-years in treated men). A small increase with SGLT2 inhibitors is possible and is labelled as a rare risk, but neither RCTs nor the best cohort show a significant increase. The FDA counts are correctly quoted, but report counts over different periods are not a risk comparison.
Why some studies weigh more
Active-comparator cohort data and RCT meta-analysis weigh more than spontaneous reports.
Is a causal relationship established? Possible, not established Plausible via genital infections (a confirmed SGLT2i effect), but not demonstrated.
Remaining uncertainty
True incidence ratio; risk in women.
Justified conclusion
Possible rare risk; the numbers are correct but do not prove higher risk.
Why do studies seem to disagree?
Spontaneous reports increased after the 2018 FDA warning (stimulated reporting), whereas cohort and RCT data measure incidence; they answer different questions.
Does this depend on the country?
- General biological effects
- Drug pharmacology and physiology are universal.
- Eating habits
- Prolonged fasting, Ramadan fasting and very-low-carbohydrate eating change the risk of hypoglycaemia and ketoacidosis with some drugs; relevant in Egypt and among Muslims in Europe.
- Origin of the food
- Not applicable.
- Contaminants
- Not applicable.
- National production conditions
- Not applicable (same active substances; generics widely used in Egypt).
- Legal rules
- Drug labels and warnings are set by FDA/EMA and national regulators; Egyptian labelling not reviewed.
- Actual monitoring data
- No Egypt-specific pharmacovigilance data were found for this outcome.
A regional difference that changes the conclusion is not supported by robust data.
Statistical re-check
- Crude rate ratio and absolute excess – Crude IRR 1.55; adjusted excess 6.7/100,000 PY (CI -2.8 to 16.1) = at most about 1 case per 15,000 PY. recalculated
- Report counts per year – 9.2 vs 0.54 reports/year; not a risk ratio. recalculated
Certainty of the overall evidence (GRADE, simplified)
- Main outcome
- Fournier gangrene with SGLT2i vs comparators
- Starting level
- high (randomised trials)
- Reasons for downgrading
- imprecision (very few events)
- inconsistency (reports vs RCTs)
- Result
- low
Simplified assessment by a single reviewer, following the GRADE approach; not a formal GRADE panel. GRADE rates the body of evidence for one outcome, not individual studies.
Clinical guidelines and official statements checked
- ADA: 9. Pharmacologic Approaches to Glycemic Treatment: Standards of Care in Diabetes-2026 (Diabetes Care 2026;49 Suppl 1) (2026) · Original publication
Necrotizing fasciitis of the perineum (Fournier gangrene): rare; prompt treatment if suspected. - NICE: Type 2 diabetes in adults: management (NG28), last updated 18 February 2026 (2026) · Original publication
Rarer events like DKA or Fournier gangrene affect 1 in 1,000 or fewer.
Search strategy
Documented literature searches for this review (search strings in the original database syntax).
| Database | Date | Search | Looking for | Hits | Included |
|---|---|---|---|---|---|
| PubMed | 26 October 2026 | (Fournier*[ti] OR "necrotizing fasciitis"[ti] OR "genital infection*"[ti]) AND (SGLT2[tiab] OR "SGLT-2"[tiab] OR "sodium-glucose"[tiab] OR gliflozin[tiab]) AND (cohort[tiab] OR meta-analysis[pt] OR pharmacovigilance[tiab]) | both directions | 21 | |
| NICE NG28 (2026) | 26 October 2026 | Fetched https://www.nice.org.uk/guidance/ng28/chapter/Initial-medicines; rare adverse events | guidelines | 1 | |
| ADA Standards of Care 2026, Section 9 (PubMed Central) | 26 October 2026 | Fetched https://pmc.ncbi.nlm.nih.gov/articles/PMC12690185/; Table 9.2. The diabetesjournals.org DOI landing pages returned HTTP 403; the identical article was read in PubMed Central. | guidelines | 1 |
Open questions
Incidence in women and in hot climates with dehydration.
How deeply was this checked?
4 linked studies: 2 checked in full text (0 of them with a structured risk-of-bias assessment), 2 on the basis of the abstract, 0 bibliographically only. No formal assessment with two independent reviewers and no independent human expert review has taken place yet.
Last scientific review: 26 October 2026
History of the verdict
In plain language
US regulators collected reports of a rare, severe infection of the genital area in people taking SGLT2 drugs. Reports alone cannot tell how often it really happens. A summary of 84 trials did not find a clear increase, but the condition is too rare to rule it out. Patients should seek urgent care if they get painful swelling in that area.
Studies on this claim
Studies supporting the claim (2)
-
Fournier gangrene reports with SGLT2 drugs
Bersoff-Matcha SJ et al.. Ann Intern Med 2019 · PMID 31060053 · DOI 10.7326/M19-0085Case series / case reportcited by the Tayebat archiveabstract checked★ key studyFDA received 55 reports of this rare genital infection with SGLT2 drugs; reports cannot show how often it really happens.
Does the study support the specific claim? Partly · Methodological quality: very low · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Describe Fournier gangrene cases with SGLT2 inhibitors vs other agents
- How was the study done?
Descriptive case series of FDA FAERS reports and published cases
- How many people, animals or samples were studied?
55 SGLT2 cases; 19 comparator cases; Adults with diabetes reported to FAERS
- What was actually found?
55 vs 19 reports.
- How large was the observed effect?
not estimable
- What do the results mean in everyday life?
Be alert to genital pain/swelling.
- What are the study's limitations?
No incidence/causality; Reporting bias (stimulated reporting after warnings); Different time windows
- What does it say about Elawady's specific claim?
Supports C-ODD-08 (signal).
- Do the results apply to Germany and Europe?
FDA data; EMA issued similar warnings (not verified).
- What can explicitly not be concluded from this study?
Incidence or causality.
-
ADA guideline 2026: diabetes medicines
American Diabetes Association Professional Practice Committee for Diabetes*. Diabetes Care 2026 · PMID 41358900 · DOI 10.2337/dc26-S009Guideline / position statementindependent cross-checkfull text checked★ key studyInsulin is essential in type 1 diabetes; SGLT2/GLP-1 drugs are recommended for heart and kidney protection; side effects listed.
Does the study support the specific claim? Partly · Methodological quality: high · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Pharmacologic glycaemic treatment
- How was the study done?
Clinical practice guideline (ADA Standards of Care 2026, Section 9)
- How many people, animals or samples were studied?
not applicable; People with type 1 and type 2 diabetes
- What was actually found?
See results.
- How large was the observed effect?
not applicable
- What do the results mean in everyday life?
Medicines chosen by benefit-risk.
- What are the study's limitations?
Partially read
- What does it say about Elawady's specific claim?
Contradicts C-INS-07, C-INS-10, C-ODD-06; supports C-ODD-07, C-INS-11.
- Do the results apply to Germany and Europe?
Consistent with ADA/EASD consensus.
- What can explicitly not be concluded from this study?
Not applicable.
No study in this group is marked as key.
Studies contradicting or limiting the claim (1)
-
Fournier gangrene in SGLT2 trials
Silverii GA et al.. Diabetes Obes Metab 2020 · PMID 31637829 · DOI 10.1111/dom.13900Meta-analysisindependent cross-checkabstract checkedAcross 84 trials Fournier gangrene was not more frequent, but cases were too few to be sure.
Does the study support the specific claim? No · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
SGLT2 inhibitors and Fournier gangrene
- How was the study done?
Meta-analysis of 84 RCTs
- How many people, animals or samples were studied?
42,415 SGLT2i vs 27,158 comparators; Type 2 diabetes in RCTs
- What was actually found?
OR 0.41 (n.s.).
- How large was the observed effect?
MH-OR 0.41 (0.09-1.82)
- What do the results mean in everyday life?
Very rare; no confirmed excess.
- What are the study's limitations?
Very few events; FG not systematically adjudicated
- What does it say about Elawady's specific claim?
Limits C-ODD-08.
- Do the results apply to Germany and Europe?
Multinational trial including European sites or directly applicable to EU practice.
- What can explicitly not be concluded from this study?
Exclude risk.
No study in this group is marked as key.
Studies with mixed or unclear results (1)
-
Fournier gangrene on SGLT2 drugs: very rare, any extra risk uncertain
Dave CV et al.. JAMA Intern Med 2019 · PMID 31479145 · DOI 10.1001/jamainternmed.2019.2813Cohort studyindependent cross-checkfull text checked★ key study15.0 vs 9.7 cases per 100,000 person-years; HR 1.73 (0.87-3.42).
Non-significant HR 1.73; very low absolute incidence.
Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Measure Fournier gangrene risk in men starting SGLT2i.
- How was the study done?
Claims-data cohort vs DPP-4i.
- How many people, animals or samples were studied?
About 500,000 men.
- What was actually found?
Very rare; possible but non-significant increase.
- How large was the observed effect?
HR 1.73 (0.87-3.42).
- What do the results mean in everyday life?
This severe infection is very rare; genital pain with fever needs urgent care.
- What are the study's limitations?
Few events.
- What does it say about Elawady's specific claim?
Shows the FDA numbers cannot establish a risk ratio.
- Do the results apply to Germany and Europe?
High.
- What can explicitly not be concluded from this study?
Causality.
No study in this group is marked as key.
Regional context
Germany / EU
EMA added a Fournier warning to SGLT2 inhibitor labels (not separately fetched; verified: false).
Egypt
Egypt has one of the highest diabetes prevalences in the region; the same drug classes and insulins are used. Access barriers and cost may make advice to stop medication attractive, which increases the practical risk of this claim. No Egypt-specific evidence changes the assessment.
What applies in my country?
General scientific assessment
Potentially true A rare possible risk, not proven in trials, that warrants vigilance.
This statement concerns biological or medical relationships. The scientific assessment above applies regardless of the country; country-specific food data do not change it.
References
- Fournier Gangrene Associated With Sodium-Glucose Cotransporter-2 Inhibitors: A Review of Spontaneous Postmarketing Cases.. Bersoff-Matcha SJ et al.. Ann Intern Med 2019 · PMID 31060053 · DOI 10.7326/M19-0085
- 9. Pharmacologic Approaches to Glycemic Treatment: Standards of Care in Diabetes-2026.. American Diabetes Association Professional Practice Committee for Diabetes*. Diabetes Care 2026 · PMID 41358900 · DOI 10.2337/dc26-S009
- Fournier's gangrene and sodium-glucose co-transporter-2 inhibitors: A meta-analysis of randomized controlled trials.. Silverii GA et al.. Diabetes Obes Metab 2020 · PMID 31637829 · DOI 10.1111/dom.13900
- Association of Sodium-Glucose Cotransporter 2 Inhibitor Treatment With Risk of Hospitalization for Fournier Gangrene Among Men.. Dave CV et al.. JAMA Intern Med 2019 · PMID 31479145 · DOI 10.1001/jamainternmed.2019.2813