Jardiance and Farxiga for Weight Loss: How Much, and Why It Stops

Jardiance and Farxiga do cause weight loss, but only a little, and neither is approved for it. In the trials on their labels, people with type 2 diabetes lost about 2 kg more than on placebo over six months, or 2.5% to 2.8% of body weight.^[1][2] The drugs make the kidneys pass sugar into the urine, which costs a few hundred calories a day. The body answers by eating more: in one 90-week study, people lost only 29% of the weight their sugar losses should have produced.^[6] In people without diabetes the gap with placebo shrinks to about 1.3 to 1.4 kg.^[9][10] These are heart, kidney and diabetes drugs that happen to move the scale. Wegovy and Zepbound, built for weight, produce five to seven times as much.

The short answer, in numbers

Two cautions on reading the table. The SGLT2 figures come mostly from six-month trials in people with diabetes, while STEP 1 and SURMOUNT‑1 ran well over a year in people without it.^[14][15] And both obesity trials counted everyone randomized, whether or not they kept taking the drug, which makes their numbers conservative. Even allowing for those differences, the SGLT2 effect is a few percent of body weight and the GLP‑1 effect is a large fraction of it.

What the labels claim

Neither label lists weight loss as a use. Jardiance is indicated to lower the risk of cardiovascular death and heart-failure hospitalization in adults with heart failure, to slow kidney decline in chronic kidney disease, to lower cardiovascular death in type 2 diabetes with heart disease, and for blood sugar control.^[1] Farxiga’s list is nearly the same: chronic kidney disease, heart failure, heart-failure admissions in type 2 diabetes, and blood sugar.^[2] Weight appears only as a measured result in the diabetes trials described in section 14.

Those results are consistent. In the Jardiance monotherapy trial, adults starting at about 78 kg lost 2.5 to 2.8 percentage points more body weight than on placebo at 24 weeks.^[1] Farxiga added to metformin produced a 2.2 kg gap.^[2] The largest gaps on either label come from trials against sulfonylureas, which cause weight gain: at two years, Jardiance users were 3.1 kg lighter than at baseline while glimepiride users were 1.3 kg heavier, and at one year Farxiga beat glipizide by 4.7 kg.^[1][2] A difference that large partly reflects the comparator gaining, not the SGLT2 inhibitor losing.

A 55-trial meta-analysis puts the class effect in diabetes at roughly 1.2 to 2.4 kg against placebo, depending on the drug and dose, with a measurable dose trend for dapagliflozin.^[3] In a 24-week trial that scanned body composition, about 1.5 of the 2.1 kg lost on dapagliflozin was fat rather than water.^[4]

Why the loss stops at a few kilograms

The arithmetic looks promising at first. The Jardiance label reports that people with type 2 diabetes pass about 64 grams of glucose a day in their urine on 10 mg and 78 grams on 25 mg; Farxiga’s label gives about 70 grams.^[1][2] At roughly 4 calories per gram of sugar, that works out to between 250 and 310 calories leaving the body every day (our calculation, not a label figure). Kept up for a year with nothing else changing, a deficit that size would take off far more than 3 kg.

Something else changes. Researchers followed 86 people on empagliflozin 25 mg for 90 weeks and fed their weight, kidney function and glucose readings into a validated model of human energy balance. The model predicted an average loss of 11.3 kg from the glucose in their urine. The actual average was 3.2 kg. To explain the gap, the model required people to have raised their food intake by about 13%, or around 270 calories a day, against about 210 calories a day of sugar lost in this group. The weight they did lose corresponded to an average deficit of only about 50 calories a day.^[6] Two of the six authors were employees of Boehringer Ingelheim, which sells Jardiance.

A second analysis, of 153 people in a year-long canagliflozin trial, put a number on the feedback. For every kilogram lost, people ate about 100 calories a day more than before they started, a pull more than three times stronger than the slowdown in calories burned.^[7] Because the drug drains calories without the person noticing, it works as a natural experiment in how hard appetite defends body weight, and these studies show that the defense is strong. A 2026 review by one of the Jardiance study’s authors sums it up in one clause: compensatory overeating “limits the degree of weight loss.”^[8]

That is the core difference from a GLP‑1. Semaglutide and tirzepatide act on the appetite itself, so the brake that stops SGLT2 weight loss is the very thing they turn down. An SGLT2 inhibitor leaves appetite untouched and then triggers it. Appetite returning on a GLP‑1 is its own subject, covered in why the appetite comes back.

Longer treatment does not change the order of magnitude. In the two-year dapagliflozin study, people were 4.5 kg below their starting weight at 102 weeks, with 77% of those randomized completing it. That figure is measured from baseline, not against placebo.^[5]

Jardiance or Farxiga for weight loss without diabetes

This is the weakest case of all. Two 2021 meta-analyses pooled the placebo-controlled trials in people with overweight or obesity and no diabetes. One, of eight trials and 750 people, found 2.3 kg lost on an SGLT2 inhibitor against 1.0 kg on placebo, a difference of 1.3 kg, with no significant change in waist size, fat mass, blood pressure or cholesterol.^[9] The other, of six trials and 872 people, found a 1.4 kg difference and graded the evidence for it very low quality.^[10]

One trial in this group used canagliflozin, a third drug in the class: 376 adults without diabetes lost 2.2% to 2.9% of their weight in 12 weeks, against 1.3% on placebo, and women had more genital yeast infections.^[11] A smaller effect without diabetes is what the mechanism predicts. How much sugar reaches the urine depends on how much the kidney filters, which rises with blood glucose.^[6] With normal blood sugar there is simply less to spill. That reasoning is inference; the trials show the smaller result directly.

Many people without diabetes do take these drugs, for heart failure or chronic kidney disease, and neither of those label indications requires diabetes.^[1][2] Weight in those patients barely moves. In DELIVER, a heart-failure trial that enrolled people with and without diabetes, dapagliflozin lowered weight against placebo by between 0.65 and 2.5 kg at a year depending on starting BMI, the most in people with the most severe obesity.^[12] The trial’s authors called it a modest extra. Its purpose was fewer hospital admissions and deaths, and its effect on those was similar across every weight category.^[12]

Side effects that matter if weight is the goal

Asking about Jardiance side effects and weight loss usually means one of two things: whether losing weight is a side effect (it is a measured effect, not a listed adverse reaction), or what the price of that weight loss is. The label answers the second.^[1]

Genital infections are the signature problem, because sugar in the urine feeds yeast. The label also warns of rare but serious infections, including Fournier’s gangrene of the perineum, and asks for urgent evaluation of genital pain or swelling with fever.^[1] For how vaginal symptoms on GLP‑1 drugs compare, see GLP-1 drugs and vaginal dryness, odor and infections. Extra urine also means less water in the body, and Farxiga’s label notes the higher urine volume that follows the glucose loss.^[2] On kidney stones the class looks protective rather than harmful in cohort studies, as set out in GLP-1 drugs and kidney stones.

The warning a dieter should read twice is ketoacidosis. Both labels list the conditions that set it off, and two of them describe a weight-loss plan: “reduced caloric intake, ketogenic diet.”^[1][2] The acid build-up can happen with blood sugar under 250 mg/dL, so a normal glucose reading does not exclude it.^[1] It is not limited to diabetes. A 2025 review collected six cases in people without diabetes who were taking an SGLT2 inhibitor for heart failure; in five, the common thread was eating little because of illness, fasting or surgery.^[13] No study has measured the risk in people taking the drug off-label to lose weight, so no rate can be given. The labels ask for the drug to be held at least three days before surgery or a procedure that requires prolonged fasting.^[1]

Who gets these drugs, and why weight is not the reason

SGLT2 inhibitors earned their place on outcome trials, not on the scale. Prescribers reach for them in three situations:

• Heart failure. Both drugs are indicated to cut cardiovascular death and heart-failure admissions in adults with heart failure, with or without diabetes.^[1][2]
• Chronic kidney disease. Both are indicated to slow the loss of kidney function and lower the risk of kidney failure in adults at risk of progression.^[1][2] How GLP‑1 drugs fit into kidney care is covered in GLP-1 drugs and your kidneys.
• Type 2 diabetes. For blood sugar, where the weight loss is a welcome side benefit rather than the aim, and for heart protection in people with established heart disease.^[1]

For someone who has one of those conditions and also wants to lose weight, the SGLT2 inhibitor is doing a job that a weight drug does not replace, and the two classes are routinely combined. For someone who has none of them and wants to lose weight, the trial record offers about a kilogram and a half, a set of infection and ketoacidosis warnings, and no approval. The drugs that are approved for weight are listed, brand by brand, on our medications page.

What to ask a prescriber

1. Why this drug, for me? If the answer is heart failure, kidney disease or diabetes, the weight change is a side note. If the answer is weight, ask why an approved weight medicine is not the choice.
2. Should I change my diet plan on it? Raise any fasting, very low-carbohydrate or ketogenic eating, since the labels list both as ketoacidosis triggers.
3. What do I do on a sick day? Ask whether to pause the drug when you cannot eat or drink normally, and when to restart.
4. What about surgery or a procedure? The labels ask for the drug to be held at least three days beforehand when prolonged fasting is involved.
5. How do I avoid genital infections? Ask what symptoms to report and when to call rather than self-treat.