Jardiance (Empagliflozin)

Empagliflozin (brand name Jardiance) is an SGLT2 inhibitor. SGLT2 is the sodium-glucose cotransporter 2 in the proximal tubule of the kidney - the transporter that normally pulls almost all filtered glucose back into the blood. Empagliflozin blocks it. The renal threshold for glucose drops and part of the sugar is excreted through urine instead of being reabsorbed.

The decisive point: this mechanism is entirely insulin-independent. It needs neither a working beta cell nor an insulin response - it operates purely through the kidney.

This information is for research and educational purposes only. No medical advice.

The kidney filters a considerable amount of glucose every day. Almost all of it is retrieved via SGLT2 before urine leaves the kidney. When the transporter is inhibited, the threshold at which sugar appears in urine shifts downward - a deliberate glucosuria results.

Three effects follow, which together explain the substance profile:

• Glucose excretion: sugar leaves the body through urine, glucose-dependent and without insulin involvement.
• Caloric outflow: calories go out with the sugar, which explains the moderate weight change observed in studies.
• Osmotic diuresis: the sugar pulls water with it, producing mild dehydration with a slight blood pressure reduction.

That osmotic component is exactly why the substance is dosed in the morning and why fluid intake features in every protocol.

Both are selective SGLT2 inhibitors and the practical effect is similar. The difference comes down to two points:

• Selectivity: Grempler et al. determined an IC50 of 3.1 nM at human SGLT2 for empagliflozin and the widest selectivity window over SGLT1 of all inhibitors tested - roughly 2500-fold, against about 1200-fold for dapagliflozin and about 250-fold for canagliflozin. SGLT1 sits mainly in the gut, so high SGLT2 selectivity means intestinal glucose uptake stays largely untouched.
• Trial data: this is the genuinely relevant difference. With EMPA-REG OUTCOME, EMPEROR-Reduced and EMPEROR-Preserved, empagliflozin has an unusually broad outcome base across diabetes, heart failure and kidney disease.

The selectivity figure sounds more impressive than it is in everyday terms. Both substances sit far above the threshold where SGLT1 stops mattering in practice. Anyone comparing the two should look at the data base, not at the fold factor.

EMPA-REG OUTCOME (Zinman et al., NEJM 2015) is the landmark work: more than 7000 participants with type 2 diabetes and established cardiovascular disease. Documented was a 14 percent reduction of the combined cardiovascular primary endpoint, driven by 38 percent fewer cardiovascular deaths and 35 percent fewer hospitalisations for heart failure. The effect appeared very early and could not be explained by glucose lowering alone - that was the actual surprise of the trial.

EMPEROR-Reduced (Packer et al., NEJM 2020) carried this into a purely cardiological population: 3730 patients with heart failure and reduced ejection fraction, hazard ratio 0.75 for the combined endpoint of cardiovascular death and heart failure hospitalisation. Crucially, the effect was independent of whether diabetes was present. That made clear the action does not hang on blood glucose.

EMPEROR-Preserved (Anker et al., NEJM 2021) extended the data to heart failure with preserved ejection fraction.

This is the most important section on this page. Rosenstock and Ferrannini analysed in Diabetes Care how ketoacidosis under SGLT2 inhibitors can occur at normal or only mildly raised blood glucose values. The reason lies in the mechanism itself: sugar drains through the kidney instead of accumulating in the blood, so the classic warning sign of high blood glucose is missing.

Contributing factors described in the literature:

• Ketogenic or heavily carbohydrate-restricted eating - the riskiest combination there is with this substance class.
• Prolonged fasting and strongly reduced food intake.
• Alcohol.
• Infections and other stress situations.
• Perioperative situations - clinical protocols pause the substance ahead of planned surgery.

Combining empagliflozin with low-carb means combining two things that push in the same direction. An unremarkable blood glucose reading is not an all-clear in that constellation.

• Genital infections: the most consistent side effect of the class. Sugar in urine is a growth medium; documented above all are mycoses, considerably more frequent in women. In EMPA-REG OUTCOME the only clearly elevated category.
• Urinary tract infections: described in the class, less clearly elevated in the empagliflozin data than genital infections.
• Volume depletion: blood pressure drop, dizziness, hypotension symptoms from the osmotic diuresis. Relevant with additional diuretic action, in older users and with low fluid intake.
• Initial creatinine rise: an early dip in estimated filtration rate that realigns over time. Long term, kidney function was better preserved in the trials than under placebo.
• Hypoglycemia in combination: low risk on its own because it is insulin-independent. With insulin or sulfonylureas it rises measurably.

Monitoring belongs with this substance: kidney function, blood pressure, fluid intake and signs of genital infections.

Store dry and protected from light, at room temperature. Out of reach of children.