Jardiance is not insulin. It belongs to a completely different drug class called SGLT2 inhibitors, and it works through a mechanism that has nothing to do with how insulin functions in the body. Jardiance is a pill you take by mouth once a day, while insulin is an injectable hormone. The two drugs lower blood sugar in fundamentally different ways, though they can sometimes be prescribed together.
How Jardiance Actually Works
Insulin lowers blood sugar by helping your cells absorb glucose from the bloodstream. Jardiance skips that process entirely. Instead, it works in your kidneys by blocking a protein called SGLT2, which is responsible for reabsorbing about 97% of the glucose your kidneys filter from your blood. When that protein is blocked, your kidneys stop reclaiming that glucose and instead flush it out through your urine.
This kidney-based approach means Jardiance doesn’t depend on how much insulin your body produces or how well your cells respond to it. It simply reroutes excess sugar out of your body before it can raise your blood sugar levels. Along with glucose, it also increases sodium and water excretion, which is why Jardiance has blood pressure-lowering effects that are separate from its impact on blood sugar. Research from the American Heart Association found that empagliflozin (the active ingredient in Jardiance) reduced blood pressure even in patients whose blood sugar barely changed, confirming these are two independent effects.
Why the Distinction Matters
Because Jardiance is not insulin, it cannot replace insulin for people who need it. People with type 1 diabetes produce little or no insulin and must inject it to survive. Jardiance is not recommended for type 1 diabetes. It’s approved for type 2 diabetes, where the body still makes some insulin but doesn’t use it efficiently. In that context, Jardiance works alongside whatever insulin your body is still producing, giving your kidneys an alternative route to clear excess sugar.
The practical differences between the two are significant. Jardiance comes as a tablet (10 mg or 25 mg) that you take once each morning, with or without food. Insulin requires injections, sometimes multiple times a day, with careful dose calculations based on meals and activity. Jardiance on its own carries a low risk of hypoglycemia (dangerously low blood sugar) because it doesn’t force your body to produce or absorb more insulin. Insulin, by contrast, can easily cause hypoglycemia if the dose is too high or a meal is skipped.
Taking Jardiance Alongside Insulin
Even though Jardiance isn’t insulin, the two are frequently prescribed together. Jardiance has been studied as an add-on therapy for people whose blood sugar remains poorly controlled on insulin alone. In clinical trials, patients on multiple daily insulin injections (more than 60 units per day) added Jardiance to their regimen and saw additional blood sugar improvement over 18 weeks. A separate trial followed patients on insulin, with or without other oral medications, for 78 weeks with Jardiance added on top.
There’s one important caution with this combination: when Jardiance is paired with insulin, the risk of hypoglycemia goes up. Your doctor will typically lower your insulin dose when adding Jardiance to compensate. The same applies if you take Jardiance with sulfonylureas, another class of diabetes medication that stimulates insulin release.
Jardiance Is Approved Beyond Diabetes
One of the reasons Jardiance sometimes confuses people is that it’s prescribed for conditions that have nothing to do with blood sugar. The FDA has approved it for four distinct uses: improving blood sugar control in adults and children 10 and older with type 2 diabetes, reducing the risk of cardiovascular death in adults with type 2 diabetes and heart disease, reducing the risk of cardiovascular death and hospitalization in adults with heart failure, and slowing kidney disease progression in adults with chronic kidney disease at risk of getting worse.
The heart failure and kidney disease approvals are especially notable because they apply regardless of whether a patient has diabetes at all. The benefits appear to come from the way Jardiance changes kidney filtration, sodium handling, and fluid balance rather than from blood sugar reduction alone. This is another clear separation from insulin, which has no direct role in treating heart failure or kidney disease.
Key Side Effects Compared to Insulin
Because Jardiance sends extra glucose into your urine, it creates an environment where urinary tract infections and genital yeast infections are more common. These are side effects insulin doesn’t cause. The sugar-rich urine provides a food source for bacteria and yeast, making these infections the most distinctive risk of SGLT2 inhibitors as a class.
Jardiance can also cause a rare but serious condition called diabetic ketoacidosis, where acids build up in the blood. This is unusual because ketoacidosis with Jardiance can occur even when blood sugar levels appear normal, which can delay diagnosis. Insulin therapy carries its own risks, most notably hypoglycemia and weight gain, neither of which is a primary concern with Jardiance alone. In fact, Jardiance tends to cause modest weight loss because you’re literally excreting calories as glucose in your urine.
Cost and Availability
Jardiance is currently available only as a brand-name medication, with no generic version on the market. This makes it significantly more expensive than many insulin formulations, particularly older generic insulins. If cost is a barrier, manufacturer savings programs and insurance coverage can vary widely, so it’s worth checking your specific plan.