How do you use Glucagon-like peptide-1 (GLP-1) receptor agonists, such as liraglutide (Victoza) or semaglutide (Ozempic), in diabetic patients during Ramadan?

GLP-1 Receptor Agonists During Ramadan

GLP-1 receptor agonists (liraglutide, semaglutide) are among the safest and most effective options for diabetic patients fasting during Ramadan because they provide glucose control with minimal hypoglycemia risk and typically require no dose adjustment. 1, 2, 3

Why GLP-1 Agonists Are Ideal for Ramadan

• GLP-1 analogues are uniquely suited for Ramadan fasting because they maintain glycemic control while carrying very low propensity for hypoglycemia during prolonged periods without calorie intake. 3

• The glucose-dependent mechanism of insulin secretion means these agents only work when blood glucose is elevated, making them inherently safer during fasting states compared to sulfonylureas or insulin. 4

• Studies demonstrate that GLP-1 agonists can be safely used during Ramadan in both diabetic and non-diabetic patients without significant adverse events. 4

Practical Management Algorithm

Pre-Ramadan Assessment (2-4 weeks before)

• Evaluate hypoglycemia risk stratification - patients on GLP-1 agonists alone fall into the low-risk category for fasting complications. 5

• Confirm adequate hydration capacity during non-fasting hours (1.5-2 L between sunset and predawn meals). 1

• Screen for absolute contraindications to fasting: acute coronary syndrome, advanced heart failure, severe aortic stenosis, poorly controlled arrhythmias, or recent cardiac procedures. 6

Dosing During Ramadan

• No dose adjustment is typically required for GLP-1 receptor agonists during Ramadan. 2, 5

• Continue the same dosing schedule established before Ramadan - weekly injections (semaglutide) or daily injections (liraglutide) can be maintained without timing changes. 3

• If the patient is on combination therapy with GLP-1 plus other agents, address those medications separately (see below). 3

Combination Therapy Considerations

When GLP-1 is combined with sulfonylureas:

• Reduce sulfonylurea dose by at least 50% or discontinue entirely to prevent hypoglycemia, as the combination increases hypoglycemic risk. 7, 5

• For once-daily sulfonylureas (glimepiride, gliclazide MR): give the full dose at sunset meal (Iftar). 1, 8

• For twice-daily sulfonylureas: use half the usual morning dose at predawn meal (Suhur) and full dose at sunset meal. 1, 8

• Avoid chlorpropamide and glyburide completely during Ramadan due to prolonged hypoglycemia risk. 1, 5

When GLP-1 is combined with metformin:

• Metformin carries minimal hypoglycemia risk and can be continued safely. 1, 6

• Adjust timing: two-thirds of total daily dose immediately before sunset meal, one-third before predawn meal. 1, 6

When GLP-1 is combined with insulin:

• This combination requires significant caution and intensive glucose monitoring. 1

• Reduce basal insulin dose by 20-30% at the start of Ramadan. 5

• Consider switching to basal-only regimens during fasting to minimize hypoglycemia risk. 1

Monitoring Requirements

• Self-monitor blood glucose closely during the first 3-4 weeks of Ramadan, particularly in the first few hours after starting the fast and in the late afternoon before breaking fast. 7, 8

• Break the fast immediately if blood glucose drops below 70 mg/dL (some guidelines suggest 60 mg/dL threshold). 8, 5

• Monitor for dehydration, which can increase thrombotic risk, especially in patients on anticoagulation. 6

Critical Safety Points

• Type 1 diabetes patients should be strongly advised against fasting regardless of GLP-1 use, as they remain at very high risk for severe hypoglycemia and diabetic ketoacidosis. 1, 6

• Patients with type 2 diabetes on GLP-1 monotherapy have quite low fasting risk and can safely observe Ramadan with appropriate education. 6, 3

• Ensure adequate hydration during non-fasting hours - distribute fluid intake from sunset to predawn to prevent dehydration and urinary stone formation. 1

• Avoid restricting eating window to less than 8 hours, as this significantly increases cardiovascular mortality risk. 6

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. 6

• Break the fast with a small, balanced meal containing fiber, protein, and complex carbohydrates to avoid rapid eating or overconsumption. 1

• Avoid caffeinated or sugary drinks that increase dehydration risk. 1

Common Pitfalls to Avoid

• Do not assume all diabetes medications are safe during Ramadan - while GLP-1 agonists are safe, many other agents (especially sulfonylureas and insulin) require significant adjustment. 1, 5

• Do not continue full-dose sulfonylureas when combined with GLP-1 therapy during Ramadan, as this substantially increases severe hypoglycemia risk. 7, 5

• Do not neglect pre-Ramadan education - waiting until Ramadan starts to adjust medications increases complication risk. 5

• Avoid SGLT2 inhibitors during Ramadan due to increased dehydration risk, despite their low hypoglycemia profile. 1