Short answer: Xigduo XR combines dapagliflozin, the drug in Farxiga, with extended-release metformin.12 Farxiga is 5 or 10 mg once daily and is also approved for chronic kidney disease and heart failure in adults, with or without diabetes. Xigduo XR is one tablet each morning with food, and its heart and kidney uses are limited to adults with type 2 diabetes. Only Xigduo XR has a boxed warning, for lactic acidosis.
| Farxiga | Xigduo XR | |
|---|---|---|
| What it contains | Dapagliflozin, an SGLT2 inhibitor1 | Dapagliflozin and extended-release metformin2 |
| Approved for | Blood sugar in adults and children 10 and older with type 2 diabetes; kidney decline in adults with chronic kidney disease; heart death and heart failure events in adults with heart failure; heart failure hospital stays in adults with type 2 diabetes and heart disease or risk factors1 | Blood sugar in adults and children 10 and older with type 2 diabetes; the same kidney and heart uses only in adults with type 2 diabetes2 |
| How taken | Once daily, with or without food1 | Once daily in the morning with food, swallowed whole2 |
| Dose | Blood sugar: 5 mg, up to 10 mg; kidney and heart uses: 10 mg1 | Up to dapagliflozin 10 mg and metformin 2,000 mg a day2 |
| Kidney limits | For blood sugar, not recommended below an eGFR of 45; kidney and heart uses not started below 251 | Not used below an eGFR of 30; starting not recommended at 30 to 452 |
| Side effects in label trials | 12-trial pool: female genital yeast infection 6.9% on 10 mg vs 1.5% on placebo, urinary tract infection 4.3% vs 3.7%1 | 8-trial pool, all on metformin: female genital yeast infection 9.3% on 10 mg vs 1.5%, urinary tract infection 5.5% vs 3.6%2 |
| Boxed warning | None1 | Lactic acidosis2 |
Both labels carry the dapagliflozin warnings: ketoacidosis even with blood sugar below 250 mg/dL, fluid loss and low blood pressure, urinary and genital infections including Fournier's gangrene, and low blood sugar with insulin or a sulfonylurea. Both say to hold the tablet for at least 3 days, if possible, before surgery with long fasting.12 Xigduo XR adds the metformin warnings: lactic acidosis and lower vitamin B12, with blood counts yearly and B12 every 2 to 3 years, and stops around some contrast scans. In trials of extended-release metformin alone, diarrhea was 9.6% vs 2.6% on placebo.2 These numbers come from separate trials with different people, lengths and methods, so they are not a head-to-head comparison.
Which, if either, fits is for your prescriber. More detail: Farxiga side effects, Xigduo XR side effects, the Farxiga and Xigduo XR dosing schedules, the Farxiga missed-dose page, and Synjardy vs Xigduo XR: how do the two SGLT2 and metformin tablets differ?.