XIGDUO XR
Clinical safety rating: caution
Comprehensive clinical and safety monograph for XIGDUO XR (XIGDUO XR).
XIGDUO XR is a combination of dapagliflozin, an SGLT2 inhibitor that reduces renal glucose reabsorption, and metformin, an AMPK activator that decreases hepatic glucose production and increases insulin sensitivity.
| Metabolism | Dapagliflozin: Primarily via UGT1A9; Metformin: Not metabolized, excreted unchanged in urine. |
| Excretion | Dapagliflozin: renal (75% as unchanged drug and glucuronide metabolites); fecal (21%). Metformin: renal (90% unchanged) via tubular secretion. |
| Half-life | Dapagliflozin: terminal half-life ~12.9 hours after single dose, supporting once-daily dosing. Metformin: plasma elimination half-life ~6.2 hours; prolonged in renal impairment. |
| Protein binding | Dapagliflozin: ~91% bound to plasma proteins (albumin). Metformin: negligible binding to plasma proteins (<5%). |
| Volume of Distribution | Dapagliflozin: apparent Vd ~118 L; extensive tissue distribution. Metformin: Vd 654±358 L (mean±SD); distributes into erythrocytes and tissues. |
| Bioavailability | Dapagliflozin: absolute oral bioavailability ~78% (tablet). Metformin: absolute oral bioavailability 50-60% (immediate-release); XR formulation 100% relative to IR (bioequivalent under fed conditions). |
| Onset of Action | Dapagliflozin: onset of urinary glucose excretion within 3 hours; glycemic effects seen after 1-2 days. Metformin: onset of glucose-lowering effect within 24-48 hours; maximal effect in 1-2 weeks. |
| Duration of Action | Dapagliflozin: >24 hours due to half-life; once-daily dosing provides sustained SGLT2 inhibition. Metformin: 8-12 hours per dose; extended-release formulation allows once-daily dosing with peak at 7 hours. |
| Molecular Weight | 408.88 |
| Brand Substitutes | Switdapa M 10mg/1000mg XR Tablet, Dapazol M 10/1000 Tablet ER, Gluflozin MF Forte 10/1000 Tablet ER, Justoza M 10mg/1000mg Tablet ER, Zinodap M 10/1000 Tablet ER, Dapamac M 10mg/500mg Tablet ER, Justoza-M 10/500 Tablet ER, Sgltd M 10mg/500mg Tablet ER, Zinodap M 10mg/500mg Tablet ER, Switdapa-M 10/500 XR Tablet |
XIGDUO XR (dapagliflozin/metformin ER) usual starting dose: 5 mg dapagliflozin/500 mg metformin once daily, with gradual dose escalation based on glycemic response; maximum dose: 10 mg dapagliflozin/2000 mg metformin once daily.
| Dosage form | TABLET, EXTENDED RELEASE |
| Renal impairment | Contraindicated if eGFR <30 mL/min/1.73 m2. Not recommended if eGFR 30-45 mL/min/1.73 m2 (dapagliflozin component not effective). For eGFR 45-60 mL/min/1.73 m2, maximum dose is 5 mg dapagliflozin/1000 mg metformin. Discontinue if eGFR persistently falls below 45 mL/min/1.73 m2. |
| Liver impairment | Avoid use in Child-Pugh Class C (severe hepatic impairment). Use with caution in Child-Pugh Class B; metformin-associated lactic acidosis risk. No specific dose recommendation; assess liver function and consider alternative therapy. |
| Pediatric use | Safety and efficacy in pediatric patients (<18 years) have not been established. Not recommended. |
| Geriatric use | Start at lower dose (2.5 mg dapagliflozin/500 mg metformin if available; otherwise 5 mg/500 mg) with careful titration. Monitor renal function (eGFR) frequently due to age-related decline. Increased risk of hypovolemia, diuretic effects, and lactic acidosis. |
| 1st trimester | dapagliflozin + metformin: dapagliflozin not recommended in first trimester due to potential renal effects; metformin may increase neural tube defect risk, but data are limited. Insulin preferred. Avoid combination. |
| 2nd trimester | dapagliflozin associated with oligohydramnios and fetal renal impairment, especially in second and third trimesters. Avoid. Metformin may be used if benefit outweighs risk, but insulin is preferred. |
| 3rd trimester | dapagliflozin may cause neonatal renal impairment and oligohydramnios; metformin may increase risk of neonatal hypoglycemia. Avoid combination. Use insulin. |
Clinical note
Comprehensive clinical and safety monograph for XIGDUO XR (XIGDUO XR).
| Placental transfer | Dapagliflozin and metformin cross the placenta. Dapagliflozin is a substrate of BCRP transporter; placental transfer is likely. Metformin actively crosses the placenta, achieving fetal concentrations comparable to maternal. |
| Breastfeeding |
■ FDA Black Box Warning
Lactic acidosis: Metformin-associated lactic acidosis is rare but fatal. Risk factors include renal impairment, acute heart failure, sepsis, dehydration, alcohol intake, and use of contrast agents. Discontinue if suspected.
| Serious Effects |
Severe renal impairment (eGFR <30 mL/min/1.73 m²)End-stage renal disease or dialysisAcute or chronic metabolic acidosis, including diabetic ketoacidosisHypersensitivity to dapagliflozin, metformin, or any componentIntravascular volume depletion (e.g., due to concurrent diuretic therapy, acute illness)
| Precautions | Lactic acidosis risk, Acute kidney injury and impairment in renal function, Volume depletion, hypotension, and electrolyte imbalances, Ketoacidosis in type 2 diabetes, Urosepsis and pyelonephritis, Lower limb amputation risk (dapagliflozin), Necrotizing fasciitis of the perineum (Fournier gangrene), Hypoglycemia when used with insulin or insulin secretagogues, Vitamin B12 deficiency (metformin), Genital mycotic infections, Increased LDL-C (dapagliflozin) |
| Food/Dietary | Take with food to reduce metformin gastrointestinal side effects. Avoid excessive alcohol consumption (can increase risk of lactic acidosis with metformin). No specific food restrictions for dapagliflozin component. |
Loading safety data…
| Dapagliflozin is excreted in human milk in low amounts; potential for adverse effects on renal development in the infant. Metformin is excreted in milk in concentrations similar to plasma; limited data suggest no adverse effects in breastfed infants. However, due to dapagliflozin, breastfeeding is not recommended during therapy. |
| Lactation Rating | L4 (dapagliflozin); L2 (metformin). Overall: Avoid combination. |
| Teratogenic Risk | XIGDUO XR (dapagliflozin/metformin extended-release) is contraindicated in the second and third trimesters due to dapagliflozin component causing increased neonatal renal morbidity and mortality. First trimester: limited data but animal studies show fetal renal toxicity at maternal exposures; caution advised. Metformin is generally low risk but associated with reduced birth weight. Overall, risk potential for urogenital and renal developmental toxicity, especially after organogenesis. |
| Fetal Monitoring | Monitor renal function (serum creatinine, eGFR) and fetal growth via ultrasound. Assess for polyhydramnios and fetal renal abnormalities. Maternal monitoring: blood glucose, HbA1c, and blood pressure. During lactation, monitor infant for hypoglycemia and growth. |
| Fertility Effects | Metformin may improve fertility in women with PCOS by restoring ovulation. Dapagliflozin: no direct effect on fertility in animal studies, but weight loss may affect menstrual cycles. Male fertility: no significant adverse effects reported. Overall, potential indirect positive effect on fertility in insulin-resistant states. |
| Clinical Pearls | XIGDUO XR is a fixed-dose combination of dapagliflozin (SGLT2 inhibitor) and metformin XR. For patients with eGFR 30-45 mL/min/1.73m², dapagliflozin dose is limited to 5 mg; metformin is contraindicated if eGFR <30. Avoid in type 1 diabetes and DKA history. Monitor for volume depletion, especially with loop diuretics. Risk of necrotizing fasciitis of perineum (Fournier’s gangrene) requires immediate discontinuation if symptoms occur. Assess renal function before initiation and periodically. Metformin may cause lactic acidosis; hold for 48 hours after contrast dye administration or before surgery. |
| Patient Advice | Take one tablet once daily with food; swallow whole, do not crush or chew. · Report symptoms of genital mycotic infections, urinary tract infections, or ketoacidosis (nausea, vomiting, abdominal pain, confusion, unusual sleepiness). · Stop taking and seek immediate medical care for any pain, tenderness, redness, or swelling in the genital or perineal area. · Avoid excessive alcohol intake while taking metformin to reduce risk of lactic acidosis. · Maintain adequate fluid intake to prevent dehydration and hypotension. · Inform healthcare provider if you become pregnant or are planning pregnancy; XIGDUO XR is not recommended during pregnancy. · Monitor blood glucose regularly as directed; do not skip doses. |