How Much Weight Can You Lose With Dapagliflozin?

Dapagliflozin, sold as Farxiga, is a diabetes pill that usually brings a modest, gradual weight loss, not the dramatic drop seen with injectable weight-loss drugs. For most people with type 2 diabetes that means about 2 to 3.5 kg (roughly 4 to 8 lb) over six months to a year, or 2 to 4% of body weight, and about 2 kg of that is beyond what they would lose anyway. The loss happens because the pill makes your body throw away sugar, and its calories, in your urine every day. How much any one person loses varies a lot, and what you eat can make the difference larger or erase much of it.

The Realistic Number for Most People

Over 24 weeks, people taking dapagliflozin with metformin lost about 2 kg (roughly 4.5 lb) more than people on a dummy pill.¹ A similar placebo-adjusted loss of about 2.1 kg was seen when it was added to metformin plus a sulfonylurea.² Their waists shrank by about 1.5 cm more than the comparison group’s.³ In everyday primary care, people averaging 75 kg went down to about 71.4 kg after a year, a loss of roughly 3.4 kg (about 7.5 lb).⁴

The “more than placebo” wording matters because people in trials also lose some weight from diet advice and the extra attention. The drug’s own share is the gap between the groups, about 2 kg. If you lose 5 kg, part of that likely came from your own changes, which is why advertised totals and trial gaps differ.

For a person weighing 100 kg (220 lb), 3% is 3 kg, or about 6.6 lb.

About 6 in 10 people lost at least 3% of their weight in a year of treatment.⁵ On the drug, about a quarter more people lost at least 5% of their weight than on placebo.⁶

Averages hide a wide spread. Some people lose well beyond the average and some lose almost nothing, so how much weight you lose says little about whether the drug is working for its main purposes. Weight tends to fall over the first several months and then level off, so judge your result after a few months of steady use, not a few weeks. Weigh at the same time of day so normal water swings don’t mislead you.

GLP-1 drugs like semaglutide commonly produce much larger losses. Dapagliflozin is prescribed mainly for blood sugar and for heart and kidney protection, and weight loss is a side benefit.

Why the Pill Makes You Lose Weight

Dapagliflozin belongs to a group of drugs called SGLT2 inhibitors. Normally your kidneys filter sugar out of the blood and then reclaim nearly all of it. These drugs block a major part of that reclaiming step, so the sugar leaves in urine along with the calories it carries. People with type 2 diabetes can pass up to about 70 g of sugar a day this way, roughly 280 calories.⁷ That works like a small daily calorie deficit without eating less. Because all this happens in the kidneys, it doesn’t depend on insulin, which is why the drug can work alongside other diabetes medicines.

The first weeks look different from the rest. You may urinate more often in the first days, and a quick drop of 1 kg or so can come mainly from water, because extra sugar in urine pulls water out with it.⁸ The scale may then seem to stall before slower fat loss builds.⁹ Staying hydrated matters during this early phase. Meanwhile the body shifts toward burning fat instead of sugar and makes more ketones, a fuel made from fat.¹⁰¹¹

Two hundred eighty calories a day would in theory add up to many kilograms a year. In practice the body pushes back, often through more hunger, and people tend to eat a bit more without noticing. That gap is why real losses level off at a few kilograms.

The amount of sugar spilled also depends on how much sugar is in your blood. As your diabetes control improves, less sugar is spilled, so the calorie loss may shrink over time.

Fat, Not Muscle, Makes Up Most of the Loss

Over six months, weight lost on dapagliflozin came mainly from fat, and muscle mass did not drop significantly.¹² On average about two-thirds of the weight lost is fat, about 2 to 3 kg.¹³

A pound of fat lost and a pound of muscle lost are not equivalent for health, because muscle supports strength, movement and blood sugar control. Losing mostly fat while keeping muscle is the more favorable pattern for someone with diabetes. Early water loss shows up on the scale but is not fat, so the scale alone overstates how much fat has gone.

Visceral fat, the deep belly fat around organs linked to heart disease and diabetes, shrank about 13% in one group with fatty liver.¹⁴ The fat surrounding the heart also shrank in people with heart failure and diabetes.¹⁵

Strength exercise helps protect muscle while you lose weight, which matters especially as you age, since muscle loss raises fall and frailty risk. Diets alone often take some muscle along with fat, and enough protein supports muscle during weight loss.

Why Some People Lose More Than Others

Your lab report may list eGFR, an estimate of how well your kidneys filter blood. Because the drug works through the kidneys, people with an eGFR above about 96 were about three times as likely to lose at least 3%.¹⁶ A kidney that filters well has more sugar to block and spills more of it.

People over 70 were about three times as likely to lose significant weight on this drug class.¹⁷ A starting BMI above 25 was slightly linked to more loss.¹⁸

If your kidney function is reduced, expect less on the scale. The drug still protects the kidneys and heart even when weight loss is small. Ask your doctor what your eGFR is.

What works against the drug is extra eating. It can push people toward eating more carbohydrates, which can offset the calories lost in urine.¹⁹ Sweet drinks and snacks quietly add calories back. A food diary for a week can reveal the pattern.

How to Lose More With Diet and the Right Expectations About Dose

In a small group combining dapagliflozin with advice to cut carbohydrates, people lost an average of about 9.9 kg of body fat over a year.²⁰ That was a small group without a comparison, so not everyone should expect that much.²¹ The study target was about 100 g of carbohydrates a day, and nobody stuck to it strictly, yet the changes still helped. Focus first on sugary drinks, sweets and refined starch. Check with your doctor before trying a very low-carb diet on this drug.

In a trial pairing the drug with calorie restriction, people lost 5 kg on average versus 3.2 kg on diet alone.²² So the pill adds about 1 to 2 kg on top of a diet, while most of a large loss comes from eating changes. Because both the drug and diet changes lower blood sugar, your doctor may need to adjust other diabetes medicines, especially insulin or sulfonylureas, to avoid low blood sugar.

Dapagliflozin is usually prescribed at 10 mg a day, sometimes 5 mg. In one analysis of type 2 diabetes studies, 5 mg produced as much or more weight loss than higher doses.²³ In type 1 diabetes, 10 mg produced about 1% more weight loss than 5 mg.²⁴ Dose is chosen for blood sugar, heart or kidney goals, so don’t change it yourself.

Results Without Diabetes or With a GLP-1 Drug

Dapagliflozin is not approved as a weight-loss drug, so using it only for weight is off-label. It was developed and approved for diabetes, heart failure and chronic kidney disease, and its safety and benefit have been studied in those groups. There are no official dosing guidelines for treating obesity alone. In someone without those conditions, risks like dehydration and yeast infections remain, but the main health benefit is less clear.

People without diabetes being treated for fatty liver lost about 5 kg on average, from 98.6 to 93.3 kg.²⁵ It shows some loss is possible without diabetes, but it is not a promise for everyone. Without high blood sugar, less sugar spills into urine, so the calorie loss is likely smaller.

If you’re considering it off-label, ask whether you have a reason beyond weight, like fatty liver, heart or kidney disease. Ask what loss would count as worthwhile, and whether a dedicated weight-loss drug fits better.

Adding dapagliflozin to a GLP-1 drug brought about 2.4 kg more loss over a year.²⁶ That was less than the 4.8 kg lost by people not on a GLP-1 drug.²⁷ If you already take semaglutide or something similar, expect a small extra benefit. The combination still gets used because the two drugs lower blood sugar in different ways, and dapagliflozin adds heart and kidney protection.

Side Effects to Know Before Counting on Weight Loss

Known side effects across this drug class include fluid loss, genital fungal infections and ketoacidosis with normal-looking blood sugar.²⁸ Ketoacidosis is a dangerous acid buildup in the blood. Heavy fluid loss through urine can lead to dehydration that strains the kidneys.²⁹

Ketoacidosis is usually linked to very high blood sugar, so people and even clinicians may not suspect it when readings look normal. Symptoms matter more than the glucose number here. Watch for nausea, vomiting, belly pain, unusual tiredness or fast breathing, and seek urgent care if they appear. Risk rises with very low-carb diets, fasting, illness or heavy alcohol.

The sugar in urine feeds yeast growth in the genital area, which is why infections are more common on this drug. Typical signs are itching, redness, irritation or discharge, and they are usually treatable with antifungal medicine. Contact your doctor if you notice them, rather than waiting for them to clear up on their own.

Drink enough fluids, especially in heat or illness, and keep the genital area clean and dry. Ask about pausing the drug before surgery or during a vomiting illness. Report dizziness on standing, a sign of dehydration.