What are the recommendations for managing a Muslim patient with type 2 diabetes who is taking a Sodium-Glucose Linked Transporter 2 (SGLT2) inhibitor and plans to fast during Ramadan?

SGLT2 Inhibitors During Ramadan Fasting

SGLT2 inhibitors should be continued during Ramadan fasting at the same dose and timing with no adjustment needed, as they are safe, effective, and carry minimal hypoglycemia risk while providing cardiorenal benefits. 1

Pre-Ramadan Preparation (6-8 Weeks Before)

Risk stratification and counseling must begin 6-8 weeks before Ramadan starts. 1

• Evaluate glycemic control, renal function (eGFR), hepatic status, and complete biochemical profile 2
• Screen for absolute cardiac contraindications to fasting: acute coronary syndrome, advanced heart failure, recent PCI or cardiac surgery, severe aortic stenosis, poorly controlled arrhythmias, or severe pulmonary hypertension 3, 4
• Patients with high ASCVD risk should avoid Ramadan fasting until more conclusive evidence is available 1
• Conduct trial fasting to test the current medication regimen before Ramadan begins 2
• Provide structured education on hypoglycemia/hyperglycemia symptoms and when to break the fast immediately (glucose <70 mg/dL) 2, 4

SGLT2 Inhibitor Management During Ramadan

The dose and timing of SGLT2 inhibitors remain completely unchanged during Ramadan. 1, 2

• SGLT2 inhibitors are designed to improve glycemic control while minimizing hypoglycemia risk 1
• The extended label for SGLT2 inhibitors in heart failure and chronic kidney disease (regardless of diabetes status) makes them particularly valuable for patients with cardiorenal risk factors 1
• Recent prospective data from 61 Egyptian patients showed SGLT2 inhibitors initiated during Ramadan resulted in significant HbA1c reduction, blood pressure lowering, creatinine reduction, and eGFR improvement with zero cases of hypoglycemia, dehydration, or diabetic ketoacidosis 5

Combination Therapy Adjustments

When SGLT2 inhibitors are combined with other medications, only the other agents require adjustment:

Metformin Timing

• Adjust to two-thirds of total daily dose immediately before sunset meal (Iftar) and one-third before predawn meal (Suhur) 2, 3, 4

Sulfonylureas

• Reduce dose by at least 50% or discontinue entirely when combined with SGLT2 inhibitors to prevent hypoglycemia 4
• If continuing sulfonylureas: for once-daily dosing, shift entire dose to before sunset meal; for twice-daily dosing, give half the usual morning dose at predawn and full dose at sunset 3

Insulin or Insulin Secretagogues

• Coadministration with SGLT2 inhibitors increases hypoglycemia risk and requires significant dose reduction 6

Monitoring During Ramadan

Self-monitor blood glucose closely during the first 3-4 weeks, particularly in the first few hours after starting the fast and late afternoon before breaking fast. 2, 4

• Break the fast immediately if blood glucose drops below 70 mg/dL 2, 4
• Monitor for dehydration signs, as SGLT2 inhibitors increase urine volume and frequency, which may enhance volume depletion risk when combined with fasting 6
• Ensure adequate hydration during non-fasting hours (between sunset and predawn) 3, 4

Critical Safety Considerations

Volume depletion is the primary concern with SGLT2 inhibitors during Ramadan:

• Coadministration with diuretics increases urine volume and frequency of voids, enhancing potential for volume depletion 6
• Fluid restriction during fasting increases thrombotic event risk, particularly in older patients with hypertension and dyslipidemia 3
• Adequate hydration during non-fasting periods is essential 3, 4

Diabetic ketoacidosis (DKA) risk, though rare, requires awareness:

• SGLT2 inhibitors carry a postmarketing warning for ketoacidosis 6
• However, the 2025 prospective study showed zero DKA cases in 61 patients using SGLT2 inhibitors during Ramadan 5

Nutritional Guidance

Distribute calories over two to three smaller meals during the non-fasting interval rather than one large meal at sunset to prevent postprandial hyperglycemia. 4

• Break the fast with a small, balanced meal containing fiber, protein, and complex carbohydrates 4
• Avoid rapid eating or overconsumption 4
• Avoid caffeinated or sugary drinks that increase dehydration risk 4

Post-Ramadan Management

Return the therapeutic regimen to pre-Ramadan schedule (dose and timing) after Ramadan ends. 2

• Assess overall health, complications, and glycemic control after Ramadan 2
• Review the fasting experience to guide future Ramadan planning 2

Common Pitfalls to Avoid

• Do not assume all diabetes medications are safe during Ramadan - sulfonylureas and insulin require significant adjustments even when combined with SGLT2 inhibitors 4
• Do not use urine glucose tests or 1,5-anhydroglucitol (1,5-AG) assays for monitoring glycemic control in patients on SGLT2 inhibitors, as these measurements are unreliable 6
• Do not continue full-dose sulfonylureas when combined with SGLT2 inhibitors, as this substantially increases severe hypoglycemia risk 4