Jardiance Safety Signals & FDA Actions: What Clinicians and Patients Need to Know

How Empagliflozin Works: The SGLT2 Mechanism

Empagliflozin blocks the sodium-glucose cotransporter-2 (SGLT2) protein in the S1 segment of the proximal renal tubule. Under normal physiology, SGLT2 reabsorbs roughly 90% of the 180 grams of glucose filtered daily by the kidneys. Blocking it causes that glucose to spill into the urine, lowering plasma glucose independent of insulin secretion. This mechanism also produces osmotic diuresis and natriuresis, which reduce preload, afterload, and cardiac filling pressures.

SGLT2 vs. SGLT1: Why Selectivity Matters

Empagliflozin is approximately 2,500-fold more selective for SGLT2 than for SGLT1 [1]. SGLT1 handles intestinal glucose absorption; high SGLT1 inhibition in the gut can cause diarrhea. Empagliflozin's selectivity largely spares SGLT1, reducing that risk compared to less-selective agents in the same class.

Hemodynamic and Renal Tubular Effects

Beyond glycosuria, empagliflozin reduces intraglomerular pressure by triggering tubuloglomerular feedback. Sodium delivered to the macula densa causes afferent arteriolar constriction, which lowers hyperfiltration. This is the proposed mechanism behind the 39% reduction in the composite of sustained eGFR decline, end-stage kidney disease, or kidney-related death seen in EMPA-KIDNEY (N=6,609) [2]. Systolic blood pressure drops by 3 to 5 mmHg on average without compensatory tachycardia, an effect attributed to the natriuretic rather than diuretic action [3].

Ketogenic Shift

Glycosuria lowers insulin demand. Lower insulin promotes lipolysis and hepatic ketogenesis. This ketogenic shift is the biochemical substrate of empagliflozin-associated diabetic ketoacidosis (DKA), which can occur even when blood glucose is only mildly elevated. The FDA first flagged this signal in 2015 and later issued a Drug Safety Communication specifically covering SGLT2 inhibitor-associated euglycemic DKA [4].

FDA Approval Timeline and Label Updates

2014: Initial Type 2 Diabetes Approval

The FDA approved empagliflozin 10 mg and 25 mg tablets on August 1, 2014, as an adjunct to diet and exercise for adults with type 2 diabetes. The approval was based on a Phase III program showing HbA1c reductions of 0.5 to 0.7 percentage points versus placebo at 24 weeks [5].

2016: Cardiovascular Risk Reduction Indication

Following EMPA-REG OUTCOME (N=7,020), the FDA expanded the label in December 2016 to include reducing the risk of cardiovascular death in adults with type 2 diabetes and established cardiovascular disease. EMPA-REG OUTCOME found a 38% relative risk reduction in CV death (hazard ratio 0.62; 95% CI 0.49 to 0.77; P<0.001) with empagliflozin 10 mg or 25 mg versus placebo over a median of 3.1 years [6]. The trial enrolled 7,020 patients across 42 countries.

"The cardiovascular mortality reduction with empagliflozin was evident as early as three months after randomization," noted the EMPA-REG OUTCOME investigators writing in the New England Journal of Medicine, "suggesting a hemodynamic mechanism rather than a purely atherosclerotic one." [6]

2016: DKA Safety Communication

The FDA's Drug Safety Communication on DKA across the SGLT2 class (May 2015, updated 2016) required label changes noting that DKA had been reported with empagliflozin even when glucose was <250 mg/dL [4]. Patients presenting with metabolic acidosis, nausea, abdominal pain, or malaise should be evaluated for DKA regardless of glucose level.

2018: Fournier Gangrene Warning

In August 2018, the FDA issued a Drug Safety Communication requiring all SGLT2 inhibitor labels to warn about necrotizing fasciitis of the perineum (Fournier gangrene) [7]. The FDA had identified 12 cases in the FAERS database from 2013 to 2018 across the SGLT2 class. Cases occurred in both men and women, required surgical debridement, and resulted in multiple deaths. The empagliflozin label was updated accordingly.

2021: Heart Failure With Reduced Ejection Fraction

The EMPEROR-Reduced trial (N=3,730) showed that empagliflozin 10 mg reduced the primary composite of CV death or hospitalization for heart failure by 25% (HR 0.75; 95% CI 0.65 to 0.86; P<0.001) in patients with HFrEF (ejection fraction <40%) [8]. The FDA approved the HFrEF indication in August 2021.

2022: Heart Failure With Preserved Ejection Fraction

EMPEROR-Preserved (N=5,988) demonstrated a 21% reduction in the same composite endpoint in HFpEF (HR 0.79; 95% CI 0.69 to 0.90; P<0.001), the first time any glucose-lowering drug showed benefit across the full ejection fraction spectrum [9]. The FDA approved the HFpEF indication in February 2022, making empagliflozin the first drug approved for this historically treatment-resistant condition.

2023: Chronic Kidney Disease

EMPA-KIDNEY enrolled 6,609 patients with CKD (eGFR 20 to 45 mL/min/1.73m², or eGFR 45 to 90 with urinary albumin-to-creatinine ratio of at least 200 mg/g) [2]. The trial was stopped early by the Data Safety Monitoring Board for clear efficacy. Empagliflozin reduced the risk of kidney disease progression or CV death by 28% (HR 0.72; 95% CI 0.64 to 0.82; P<0.001). The FDA granted the CKD indication in July 2023.

Major Safety Signals in Detail

Diabetic Ketoacidosis

Euglycemic DKA is the most clinically deceptive risk associated with empagliflozin. The FDA's 2015 safety communication and a 2020 analysis of FAERS data identified 2,417 DKA cases across SGLT2 inhibitors from 2013 to 2019, with empagliflozin representing a substantial portion given its market share [4].

Precipitating factors identified in case series and pharmacovigilance data include:

• Insulin dose reduction or omission (especially in patients with latent autoimmune diabetes in adults, sometimes misclassified as T2D)
• Surgical procedures, prolonged fasting, or low-carbohydrate diets
• Alcohol excess
• Intercurrent illness
• Pancreatic insufficiency

The FDA label now instructs clinicians to withhold empagliflozin at least 3 to 4 days before elective surgery and in clinical situations likely to predispose to ketoacidosis. Patients should be told to seek care immediately if they develop symptoms of DKA even when glucose readings appear normal.

Genital Mycotic Infections

Glycosuria creates a glucose-rich local environment that supports fungal overgrowth. In pooled Phase III data, genital mycotic infections occurred in 5.4% of women and 3.1% of men taking empagliflozin, compared with 1.5% and 0.4% on placebo, respectively [5]. Most cases were mild to moderate and responded to standard antifungal therapy. Recurrent or persistent infections were less common but did occur. Patients should be counseled to maintain genital hygiene and to report symptoms promptly.

Urinary Tract Infections and Urosepsis

The SGLT2 mechanism increases urinary glucose, which can support bacterial growth in the bladder. Post-marketing surveillance identified cases of urosepsis and pyelonephritis requiring hospitalization. In 2015, the FDA issued a safety communication requiring label updates about this risk [10]. The package insert now advises clinicians to evaluate patients for signs and symptoms of urinary tract infections and to treat promptly. Empagliflozin should be temporarily discontinued in patients with serious urinary infections.

Fournier Gangrene

Fournier gangrene is a rare but life-threatening necrotizing fasciitis of the genitalia, perineum, or perianal area. The 12 cases identified by the FDA's 2018 review required a median hospitalization of 20 days, and several patients required multiple surgical procedures [7]. Cases occurred across different SGLT2 inhibitors and in patients without classical risk factors. Any patient on empagliflozin presenting with pain, swelling, erythema, or crepitus in the perineal region requires immediate evaluation, surgical consultation, and drug discontinuation.

Volume Depletion and Hypotension

Osmotic diuresis from glycosuria and the natriuretic effect of SGLT2 inhibition can reduce intravascular volume, particularly at treatment initiation. Symptomatic hypotension occurred in 0.5% of empagliflozin-treated patients versus 0.3% on placebo in pooled analyses [5]. Risk is highest in patients who are elderly, are on loop diuretics, or have baseline eGFR <60 mL/min/1.73m². Volume status should be assessed before starting therapy, and diuretic doses may need adjustment.

Lower Limb Amputations: A Signal Clarified

The CANVAS trial of canagliflozin (a different SGLT2 inhibitor) showed a roughly doubled amputation risk. This raised concern across the entire class. For empagliflozin specifically, EMPA-REG OUTCOME showed no significant increase in amputation rates (HR 1.05; 95% CI 0.74 to 1.50) [6]. The FDA's label for empagliflozin does not carry an amputation warning, distinguishing it from canagliflozin's label. Still, patients with peripheral arterial disease or prior amputations deserve heightened surveillance given the biological plausibility of volume depletion reducing peripheral perfusion.

Acute Kidney Injury

Paradoxically, though empagliflozin is renoprotective long-term, it can cause short-term eGFR dips at initiation, particularly in volume-depleted patients. The FDA Safety Communication from 2016 flagging AKI across SGLT2 inhibitors (driven largely by canagliflozin and dapagliflozin data) prompted a class-wide label update [10]. Empagliflozin-specific AKI signals in FAERS have been less prominent. Holding the drug during acute illness or dehydration remains standard practice.

Benefit-Risk Synthesis Across Approved Populations

The clinical calculus for empagliflozin differs meaningfully by indication. The table below organizes the benefit-risk profile by patient phenotype so that prescribers can align drug choice with individual risk.

| Patient Phenotype | Primary Benefit Signal | Key Risk to Monitor | |---|---|---| | T2D with established ASCVD | 38% RRR in CV death (EMPA-REG) | DKA, genital mycotic infection | | HFrEF (EF <40%) | 25% RRR in CV death/HF hospitalization (EMPEROR-Reduced) | Volume depletion, eGFR dip | | HFpEF (EF ≥40%) | 21% RRR in composite endpoint (EMPEROR-Preserved) | UTI, Fournier gangrene (rare) | | CKD (eGFR 20-45) | 28% RRR in kidney progression/CV death (EMPA-KIDNEY) | Glycosuria-related infections, AKI with illness | | T2D without CVD or CKD | HbA1c lowering 0.5-0.7%, BP reduction 3-5 mmHg | Genital mycotic infection, DKA |

In patients with heart failure, the 2022 AHA/ACC Heart Failure Guidelines assigned empagliflozin a Class I, Level of Evidence A recommendation for patients with symptomatic chronic HFrEF to reduce morbidity and mortality [11]. This is one of the highest recommendation levels in cardiology guidelines and reflects the consistency of findings across EMPEROR-Reduced and complementary SGLT2 inhibitor trials.

"SGLT2 inhibitors have become a pillar of guideline-directed medical therapy for heart failure," stated the 2022 AHA/ACC/HFSA Guideline for the Management of Heart Failure, "with strong evidence supporting their use irrespective of the presence or absence of diabetes." [11]

Contraindications and Populations Requiring Caution

Absolute Contraindications

Empagliflozin is contraindicated in:

• Patients with eGFR <20 mL/min/1.73m² (glycemic efficacy is minimal and risk accumulates)
• Known hypersensitivity to empagliflozin or any excipient
• Dialysis-dependent end-stage renal disease

Relative Cautions

Several populations require individualized assessment before prescribing:

• Type 1 diabetes: Not FDA-approved; risk of DKA is substantially higher in T1D, and trials in this population (such as EASE-2 and EASE-3) showed clear efficacy but were not pursued to approval due to the DKA signal [12].
• Recurrent UTIs: Glycosuria may worsen bacterial colonization; weigh benefit against infection frequency.
• Low body weight or frailty: Osmotic diuresis may cause clinically significant volume loss.
• Concurrent RAAS inhibitors and diuretics: Additive hypotensive and hyperkalemic potential; monitor electrolytes at 2 to 4 weeks after initiation.

Perioperative Management

Hold empagliflozin 3 to 4 days before procedures requiring general, neuraxial, or deep sedation anesthesia. Resume only when the patient is eating normally and hemodynamically stable. This guidance reflects the DKA risk in fasted, metabolically stressed patients and was incorporated into the prescribing information following FDA review [4].

Drug Interactions and Pharmacokinetic Considerations

Empagliflozin is primarily metabolized by UGT1A3, UGT1A8, UGT1A9, and UGT2B7 via glucuronidation. It is not a CYP substrate, which limits pharmacokinetic drug-drug interactions compared with many other oral diabetes agents [5]. Clinically meaningful interactions are limited but include:

• Insulin and insulin secretagogues: Additive hypoglycemia risk. Reducing insulin or sulfonylurea dose by 20 to 30% at empagliflozin initiation is often appropriate.
• Rifampin: A potent UGT inducer; co-administration reduces empagliflozin AUC by approximately 35%. Clinical significance in glycemic control is uncertain.
• Diuretics: Co-administration amplifies volume depletion. Loop diuretic doses may need reduction.

Renal excretion accounts for roughly 54% of the dose; hepatic impairment has minimal effect on empagliflozin exposure at Child-Pugh A and B levels [5].

Monitoring Protocol After Initiation

A structured monitoring plan reduces the risk of preventable adverse events. Based on the prescribing information and the ADA Standards of Medical Care in Diabetes 2024, a reasonable clinical schedule includes:

1. Baseline: eGFR, serum electrolytes, blood pressure, urinalysis. Document volume status.
2. 2 to 4 weeks: Reassess blood pressure, eGFR, potassium, and symptoms of volume depletion or UTI.
3. 3 months: HbA1c (if prescribed for T2D), eGFR trend.
4. Every 6 months ongoing: eGFR, electrolytes, genital and urinary symptom review.
5. Sick-day guidance: Provide written instruction to hold empagliflozin during gastrointestinal illness, prolonged fasting, or fever, and to seek care if symptoms of DKA appear.

The ADA 2024 Standards recommend SGLT2 inhibitors as preferred add-on therapy in T2D patients with established cardiovascular disease, heart failure, or CKD, independent of HbA1c level or baseline glucose control [13].

Pediatric and Special Population Considerations

The FDA approved empagliflozin for type 2 diabetes in patients aged 10 years and older in December 2023, based on the DINAMO trial (N=158), which showed HbA1c reductions of 0.84 percentage points versus placebo at 26 weeks in adolescents [14]. The DKA risk in younger patients with possible autoimmune diabetes misclassification deserves particular attention. Pediatric prescribers should confirm C-peptide and GAD antibody status before initiating SGLT2 therapy.

Pregnancy: Empagliflozin is not recommended during the second and third trimesters due to renal toxicity observed in animal studies and theoretical fetal osmotic diuresis. The drug should be discontinued as soon as pregnancy is detected [5].

Older adults (65 years and over): Volume depletion, falls, and urogenital infections are disproportionately common. The EMPA-REG OUTCOME subgroup for patients aged 65 and older showed preserved cardiovascular benefit, but clinicians should assess fall risk and bladder function before prescribing [6].