Diabetes management during Ramadan

Red Flags

Severe hypoglycaemia within 3 months of Ramadan, recurrent hypoglycaemia unawareness, or DKA in last 3 months — fast not recommended (very-high-risk)^[1]
Pregnancy with diabetes during Ramadan — very-high-risk; counsel against fasting; intensive monitoring if patient chooses to fast^[1]
T1DM or insulin-pump users — high-risk; pre-Ramadan structured education with insulin dose adjustments mandatory^[1]
CKD stage 3b or worse, dialysis-dependent — very-high-risk; fast not recommended without specialist clearance^[1]

Pre-Ramadan structured education^[1]
Risk assessment, glucose targets during fast, sick-day rules (when to break the fast), regimen modifications, exercise timing, hydration
Break the fast (mandatory) for^[1]
Glucose <70 mg/dL OR >300 mg/dL OR symptoms of hypoglycaemia / hyperglycaemia / dehydration / acute illness

Drug	Class	Adult	Paediatric	Notes
Metformin (no dose change typically)^[1]	Biguanide	Reverse timing: morning dose at iftar, evening dose at suhoor; no total dose change	—	Low hypoglycaemia risk; safe to fast
SGLT2 inhibitor (caution)^[1]	SGLT2 inhibitor	Continue but emphasise hydration during non-fasting hours; pause if dehydration / vomiting; consider stopping pre-Ramadan in high-risk patients	—	Risk of euglycaemic DKA and dehydration with prolonged fasting
Sulfonylurea (modify timing and dose)^[1]	Insulin secretagogue	Newer agents (gliclazide MR, glimepiride) preferred over glibenclamide; reduce morning equivalent at suhoor by 25–50%; full dose at iftar	—	Hypoglycaemia risk; avoid glibenclamide; consider switching to DPP-4 inhibitor pre-Ramadan if previously on glibenclamide
Basal-bolus insulin^[1]	Insulin therapy	Reduce basal dose by 15–30%; switch timing to evening; reduce prandial dose at suhoor by 25–50%; full prandial at iftar adjusted to carbohydrate	—	Detailed individualised plan; CGM strongly recommended; pre-Ramadan training mandatory

Metformin (no dose change typically)^[1]

Biguanide

Adult: Reverse timing: morning dose at iftar, evening dose at suhoor; no total dose change
Paediatric: —

Low hypoglycaemia risk; safe to fast

SGLT2 inhibitor (caution)^[1]

SGLT2 inhibitor

Adult: Continue but emphasise hydration during non-fasting hours; pause if dehydration / vomiting; consider stopping pre-Ramadan in high-risk patients
Paediatric: —

Risk of euglycaemic DKA and dehydration with prolonged fasting

Sulfonylurea (modify timing and dose)^[1]

Insulin secretagogue

Adult: Newer agents (gliclazide MR, glimepiride) preferred over glibenclamide; reduce morning equivalent at suhoor by 25–50%; full dose at iftar
Paediatric: —

Hypoglycaemia risk; avoid glibenclamide; consider switching to DPP-4 inhibitor pre-Ramadan if previously on glibenclamide

Basal-bolus insulin^[1]

Insulin therapy

Adult: Reduce basal dose by 15–30%; switch timing to evening; reduce prandial dose at suhoor by 25–50%; full prandial at iftar adjusted to carbohydrate
Paediatric: —

Detailed individualised plan; CGM strongly recommended; pre-Ramadan training mandatory

Break the fast immediately if glucose <70 or >300 mg/dL, or if you feel unwell — this is religiously permitted and clinically necessary^[1]
Drink plenty of fluids during non-fasting hours; avoid sugary drinks at iftar (rapid glucose spikes)^[1]
If on insulin or SGLT2, check ketones if glucose >250 or feeling unwell — euglycaemic DKA possible on SGLT2^[1]

Severe hypoglycaemia or DKA during RamadanEmergency department; reassess fasting safety post-recovery^[1]
Very-high-risk patient choosing to fast against adviceDiabetes specialist for individualised plan, intensive monitoring, CGM^[1]
Pregnancy with diabetes during RamadanJoint diabetes-obstetric care; counsel against fasting^[1]

Pre-Ramadan risk stratification and intra-Ramadan adjustments to glucose-lowering therapy for adults with diabetes who choose to fast.

1.ADA/EASD/IDF/DAR International Alliance — Recommendations for the Management of Diabetes During Ramadan: Update 2025 (2025)