Should a patient be switched from Synjardy XR (empagliflozin and metformin) to an immediate-release formulation, and is a dose adjustment of Jardiance (empagliflozin) necessary?

Understanding Synjardy XR Dosing and Potential Medication Changes

Synjardy XR should be maintained as a once-daily medication since it is a 24-hour extended-release formulation, and the empagliflozin component should be kept at standard doses of either 10mg or 25mg total daily dose as recommended by the manufacturer.

What the Pharmacy Message Means

The pharmacy is asking two important questions:

1. Whether to switch from Synjardy XR (extended-release) to immediate-release Synjardy
2. Whether to maintain standard empagliflozin (Jardiance) dosing (either 10mg or 25mg daily)

Medication Formulation Considerations

Extended-Release vs. Immediate-Release

Synjardy XR contains two medications:

• Empagliflozin (SGLT2 inhibitor)
• Extended-release metformin

The extended-release formulation offers several advantages:

• Once-daily dosing improves medication adherence
• Reduced gastrointestinal side effects compared to immediate-release metformin
• Sustained glucose control over 24 hours

Guidelines support the use of extended-release metformin formulations for improved tolerability and adherence. As noted in diabetes management guidelines, "a longer-acting formulation [of metformin] is available in some countries and can be given once per day" 1.

Empagliflozin Dosing

The FDA-approved dosing for empagliflozin (Jardiance) is:

• Standard doses: 10mg or 25mg once daily
• Starting dose: 10mg once daily, which may be increased to 25mg if needed and tolerated 2

Clinical Decision Algorithm

1. Maintain Extended-Release Formulation

   • Keep patient on Synjardy XR (once daily) unless there are specific reasons to switch:
     • Cost/insurance issues
     • Tolerability problems specific to the XR formulation
     • Need for more flexible dosing

2. Maintain Standard Empagliflozin Dosing

   • Follow manufacturer recommendation to keep empagliflozin at either 10mg or 25mg total daily
   • Do not split or use non-standard doses as this may affect efficacy and safety

3. Consider Patient-Specific Factors

   • Renal function: Empagliflozin should not be initiated if eGFR <45 mL/min/1.73m² 2
   • Metformin dosing should be adjusted if eGFR <45 mL/min/1.73m² 1
   • Cardiovascular risk: Empagliflozin has proven cardiovascular benefits 1

Evidence Supporting This Approach

Research demonstrates that the combination of empagliflozin and metformin provides:

• Sustained reductions in HbA1c and weight compared to placebo 3, 4
• Potential cardiovascular and renal benefits 5
• Bioequivalence between fixed-dose combinations and individual tablets 6

Important Considerations and Pitfalls

1. Avoid Splitting Extended-Release Tablets

   • Extended-release formulations should not be split, crushed, or chewed as this would disrupt the controlled-release mechanism

2. Monitor Renal Function

   • Regular monitoring of renal function is essential, especially if eGFR <60 mL/min/1.73m² 1
   • Empagliflozin should be discontinued if eGFR persistently falls below 45 mL/min/1.73m² 2

3. Hypoglycemia Risk

   • If the patient is also on insulin or sulfonylureas, monitor for hypoglycemia when adding or adjusting SGLT2 inhibitor therapy 1

4. Response to Pharmacy

   • Inform the pharmacy that the patient should remain on Synjardy XR as a once-daily medication
   • Confirm that the empagliflozin component should remain at standard dosing (10mg or 25mg)

In conclusion, unless there are specific contraindications or tolerability issues, maintaining the patient on Synjardy XR with standard empagliflozin dosing (10mg or 25mg) is the recommended approach based on current evidence and guidelines.