Metformin vs Empagliflozin: side effects in FDA adverse event reports
At a glance
| Metformin | Empagliflozin | |
|---|---|---|
| Drug class | – | Sodium-Glucose Cotransporter 2 Inhibitor |
| Brand names | Metformin Hydrochloride | Jardiance |
| FAERS reports | 354,745 | 66,861 |
| Serious | 69% | 61% |
| Death outcome | 29,950 | 3,360 |
| Boxed warning | Yes LACTIC ACIDOSIS Postmarketing cases of metformin-associated lactic acidosis have resulted in death, hypothermia, hypotension, and resistant bradyarrhythmias. Th | No |
Signals both drugs share
| Reaction | Metformin | Empagliflozin | Label screen (A / B) |
|---|---|---|---|
| Diabetic ketoacidosis | 4,053 · PRR 11.9 | 3,864 · PRR 60.2 | Labeled adverse reaction / Likely indication confounding |
| Euglycaemic diabetic ketoacidosis | 1,754 · PRR 46.1 | 2,037 · PRR 330.9 | Labeled (related wording) / Labeled (related wording) |
| Ketoacidosis | 1,347 · PRR 12.8 | 1,511 · PRR 79.4 | Labeled adverse reaction / Likely indication confounding |
| Diabetic metabolic decompensation | 469 · PRR 29.9 | 80 · PRR 19.2 | Labeled (related wording) / Labeled (related wording) |
| Gastrointestinal hypomotility | 384 · PRR 12.1 | 167 · PRR 25.3 | Not in label — unassessed / Not in label — unassessed |
Labeled signals distinctive to Metformin
- Acute kidney injury — n=17,231, PRR 7.4 Labeled — boxed warning
- Lactic acidosis — n=17,141, PRR 67.6 Labeled — boxed warning
- Hypoglycaemia — n=7,287, PRR 10.3 Labeled — boxed warning
- Metabolic acidosis — n=6,200, PRR 14.2 Labeled adverse reaction
- Diabetes mellitus inadequate control — n=2,895, PRR 11.4 Labeled (related wording)
- Vitamin b12 deficiency — n=630, PRR 10.8 Labeled (related wording)
- Anion gap increased — n=243, PRR 12.9 Labeled (related wording)
Labeled signals distinctive to Empagliflozin
- Fungal infection — n=2,147, PRR 21.5 Labeled (related wording)
- Genital infection fungal — n=103, PRR 44.5 Labeled adverse reaction
- Balanoposthitis — n=102, PRR 45.6 Labeled adverse reaction
- Genital infection — n=62, PRR 72.9 Labeled adverse reaction
- Phimosis — n=49, PRR 22.9 Labeled adverse reaction
- Perineal infection — n=45, PRR 90.6 Labeled (related wording)
- Urinary tract candidiasis — n=36, PRR 74.0 Labeled (related wording)
- Perineal abscess — n=35, PRR 26.5 Labeled (related wording)
Common questions
Which has more reported side effects, Metformin or Empagliflozin?
Metformin has 354,745 FAERS reports and Empagliflozin 66,861. More reports does not mean more dangerous: volume follows how widely and how long a drug has been used, prescription vs over-the-counter status, and publicity. The seriousness share (69% vs 61%) is a better like-for-like signal of the kind of problems reported.
Which side effects do Metformin and Empagliflozin share?
Both drugs carry disproportionality signals for diabetic ketoacidosis, euglycaemic diabetic ketoacidosis, ketoacidosis, diabetic metabolic decompensation, gastrointestinal hypomotility. Shared signals often reflect a shared drug class or the condition both are used for.
Is Metformin or Empagliflozin safer?
FAERS cannot answer that: it has no denominator and no comparator. Use this page to see which risks are already on each label and which signals are unlabeled, then check the prescribing information and your clinician for your situation.
Sources: openFDA FAERS pair statistics (OpenPV build 2026-09-14), FDA labels via openFDA, openFDA count queries for seriousness and deaths. Pair chosen because it is a commonly searched comparison. Generated 2026-10-08.