Can I give a patient with type 2 diabetes metformin 750 mg and Farxiga (dapagliflozin) 10 mg together, assuming no contraindications and adequate renal function?

Can You Give Metformin 750 mg and Farxiga 10 mg Together?

Yes, you can and should give metformin 750 mg with Farxiga (dapagliflozin) 10 mg together—this combination is explicitly recommended by the American Diabetes Association and FDA-approved for type 2 diabetes management. 1, 2

Evidence Supporting This Combination

• The ADA/EASD consensus explicitly states that metformin should be continued indefinitely when other glucose-lowering agents like SGLT-2 inhibitors are added, provided no contraindications exist. 3
• The FDA label for dapagliflozin (Farxiga) approves its use as adjunct therapy to diet and exercise to improve glycemic control in adults with type 2 diabetes, with no restriction against concurrent metformin use. 2
• Clinical trials demonstrate that dapagliflozin combined with metformin produces HbA1c reductions of 1.98–2.05%, weight loss of 2–4 kg, and systolic blood pressure reductions of 3–5 mmHg, with superior efficacy compared to either agent alone. 4, 5, 6

Dosing Considerations

Your metformin dose of 750 mg is below standard therapeutic dosing:

• The typical metformin target is 1,000 mg twice daily (2,000 mg total), which is the maximum effective dose for glycemic control. 3
• If the patient is on 750 mg once daily, consider titrating upward by 500 mg weekly to reach 1,000 mg twice daily, unless limited by gastrointestinal side effects or renal function. 3
• If the patient is on 750 mg twice daily (1,500 mg total), this is acceptable but suboptimal; further titration may improve outcomes. 3

Farxiga 10 mg is the correct dose for most indications:

• For glycemic control in type 2 diabetes, the FDA-approved starting dose is 5 mg once daily, which can be increased to 10 mg for additional benefit. 2
• For cardiovascular and renal protection (heart failure, chronic kidney disease), the recommended dose is 10 mg once daily regardless of baseline HbA1c. 2

Renal Function Requirements

Check eGFR before prescribing this combination:

• Metformin: Safe at standard doses when eGFR ≥ 45 mL/min/1.73 m²; reduce dose by 50% (to ~1,000 mg daily) when eGFR is 30–44; discontinue when eGFR < 30. 1, 3
• Dapagliflozin: Can be initiated at 10 mg when eGFR ≥ 25 mL/min/1.73 m² for cardio-renal protection; glucose-lowering efficacy is reduced below eGFR 45 but cardiovascular and kidney benefits persist. 1, 2
• If eGFR falls below 25 mL/min/1.73 m² while on dapagliflozin, the patient may continue the drug for organ protection but should not initiate it at that level. 2

Safety Profile of This Combination

This combination carries minimal hypoglycemia risk when used without sulfonylureas or insulin:

• Neither metformin nor dapagliflozin causes hypoglycemia as monotherapy or in combination. 1, 3
• Self-monitoring of blood glucose is generally unnecessary with this regimen. 3

Common adverse effects to counsel patients about:

• Genital mycotic infections occur in ~6–8% of patients on dapagliflozin (vs. 1–2% on metformin alone); most are mild and easily treated, but patients should maintain daily hygiene and seek care if severe. 1, 4, 5
• Urinary tract infections are slightly more common with dapagliflozin (~7–11% vs. 4–7% with metformin alone). 5
• Gastrointestinal side effects (nausea, diarrhea) from metformin can be minimized by taking with meals and slow dose titration. 3

Critical safety warning—euglycemic diabetic ketoacidosis:

• Dapagliflozin can cause ketoacidosis with minimal blood glucose elevation, especially during acute illness, surgery, or prolonged fasting. 1, 2
• Instruct patients to discontinue dapagliflozin and seek immediate care if they develop nausea, vomiting, abdominal pain, dyspnea, or unusual fatigue. 1, 2
• Withhold dapagliflozin at least 3 days before major surgery or procedures with prolonged fasting; resume when the patient is clinically stable and eating. 2

Volume depletion precautions:

• Dapagliflozin causes osmotic diuresis; assess volume status before initiation and correct depletion first. 2
• Use caution when combined with loop diuretics, ACE inhibitors, or ARBs—monitor for orthostatic hypotension, especially in older adults. 3

When to Use This Combination

This combination is appropriate in three clinical scenarios:

1. Initial combination therapy in treatment-naïve patients with HbA1c > 9% or significant hyperglycemia symptoms, to achieve rapid glycemic control. 1, 5
2. Add-on therapy when metformin alone fails to achieve HbA1c target of 7–8% after 3 months. 1, 3
3. Immediate dual therapy in patients with established cardiovascular disease, heart failure, or chronic kidney disease, regardless of baseline HbA1c, because dapagliflozin reduces cardiovascular death, heart failure hospitalization, and kidney disease progression. 1, 3

Monitoring Requirements

• Measure eGFR at baseline, 2 weeks after starting dapagliflozin, then every 3–6 months. 3
• Check vitamin B12 annually in patients on long-term metformin, especially if anemia or peripheral neuropathy develops. 1, 3
• Reassess the medication regimen every 3–6 months and adjust based on glycemic control and tolerability. 1, 3

What NOT to Do

• Do not discontinue metformin when adding dapagliflozin; combination therapy is superior to sequential monotherapy and metformin provides ongoing cardiovascular and metabolic benefits. 1, 3
• Do not add a DPP-4 inhibitor to this regimen; they do not reduce mortality or morbidity despite lowering HbA1c. 3
• Do not delay intensification beyond 3 months if HbA1c remains above target; postponing escalation worsens long-term outcomes. 3