Jardiance and Lantus Can Be Safely Combined with Appropriate Monitoring
When combining empagliflozin (Jardiance) with insulin glargine (Lantus), the primary interaction is an increased risk of hypoglycemia, requiring insulin dose reduction of approximately 10-20% at initiation. 1
Key Drug Interaction
The FDA label for Jardiance explicitly states that coadministration with insulin may require lower insulin doses to reduce the risk of hypoglycemia 1. This is a pharmacodynamic interaction—both medications lower blood glucose through different mechanisms (SGLT2 inhibition causing glucosuria versus direct insulin replacement), creating an additive glucose-lowering effect.
Practical Dosing Algorithm
When adding Jardiance to existing Lantus therapy:
- Reduce basal insulin dose by 10-20% at Jardiance initiation 2
- Monitor fasting glucose closely for the first 2-4 weeks
- Titrate insulin based on glucose response
- The glucose-lowering effect of Jardiance is dose-dependent but plateaus at eGFR <45 mL/min/1.73 m² 3
Evidence from Clinical Trials
A 78-week randomized trial specifically examined empagliflozin added to basal insulin (including glargine) in type 2 diabetes 4. Patients on empagliflozin 10 mg or 25 mg achieved:
- HbA1c reduction of 0.6-0.7% at 18 weeks versus placebo
- Significant insulin dose reduction at 78 weeks
- Critically, hypoglycemia rates were similar across all groups (35-36%), suggesting the combination is safe when properly managed
Another study confirmed that empagliflozin added to insulin regimens reduced total daily insulin requirements by 7.6 units over 12 weeks without increasing hypoglycemia 5.
Additional Monitoring Considerations
Beyond hypoglycemia, monitor for:
- Volume depletion: Jardiance causes osmotic diuresis; assess volume status before initiation, especially in patients on diuretics or with baseline hypotension 1
- Renal function: Expect a transient increase in serum creatinine (typically ≤0.1 mg/dL) within 4 weeks that stabilizes and reverses upon discontinuation 1
- Genital mycotic infections: Occurred in 5-8% of empagliflozin-treated patients in trials 4
- Diabetic ketoacidosis: Rare but serious; educate patients on sick-day management and discontinue Jardiance during illness, prolonged fasting, or before surgery 3
Cardiovascular and Renal Benefits Maintained
The combination preserves Jardiance's cardiovascular benefits. In EMPA-REG OUTCOME, empagliflozin reduced cardiovascular death by 38% and heart failure hospitalization by 35% in patients with type 2 diabetes and established cardiovascular disease 2. These benefits persist regardless of baseline insulin use 6.
Common Pitfall to Avoid
Do not discontinue or reduce Jardiance when insulin doses are increased during illness or stress. Instead, temporarily hold Jardiance during acute illness (particularly with vomiting, dehydration, or ketosis risk) and resume once stable. The insulin dose should be adjusted independently based on glucose targets 3.
The combination is guideline-supported: SGLT2 inhibitors with proven cardiovascular benefit are recommended in patients with type 2 diabetes and atherosclerotic cardiovascular disease or heart failure, independent of baseline glucose control or insulin use 7, 8.