Synopsis
Use SGLT2 inhibitors for appropriate glycaemic, heart and kidney benefit while preventing euglycaemic ketoacidosis, dehydration, genital infection and perioperative harm.
- SGLT2 inhibitors cause urinary glucose and sodium loss, with benefits in type 2 diabetes, heart failure and chronic kidney disease that extend beyond HbA1c reduction.
- The glucose-lowering effect diminishes as eGFR falls, but kidney and heart-failure protection can persist within licensed and NICE-recommended renal ranges.
- NICE's February 2026 type 2 algorithm places cardiorenal comorbidity and risk at the centre of selection; check exact product eligibility rather than treating the class as interchangeable.
- Explain genital candidiasis, polyuria, volume depletion and the rare risks of ketoacidosis and Fournier gangrene before initiation, with a written sick-day plan.
- SGLT2-associated DKA may be euglycaemic. Test blood ketones when symptoms fit, regardless of a reassuring capillary glucose.
- Pause treatment during acute serious illness, inability to eat or drink, significant dehydration and major surgery; hospitalised patients need blood-ketone monitoring under MHRA guidance.
- Do not use SGLT2 inhibitors for type 1 diabetes in routine UK practice: dapagliflozin's former type 1 indication is no longer authorised.
- An early modest eGFR dip may reflect haemodynamic change and is not automatically acute kidney injury; interpret with symptoms, volume status, potassium and later trajectory.
- Never reduce essential insulin abruptly when adding SGLT2 treatment, and avoid ketogenic diets or prolonged fasting that increase ketosis risk.
Key red flags
Nausea, vomiting, abdominal pain, tachypnoea, drowsiness or ketone odour with only modest glucose is a time-critical SGLT2 complication, especially during fasting, illness or insulin reduction.
Postural hypotension, syncope, oliguria or rising creatinine after diarrhoea, heat, diuretics or low intake indicates clinically important hypovolaemia and requires drug interruption and assessment.
Severe perineal pain, swelling, erythema, fever or malaise may precede necrosis and requires immediate broad sepsis management and surgical referral, not treatment as simple thrush.
New ulcer, infection, ischaemic pain or gangrene needs urgent multidisciplinary foot assessment and an individual decision about treatment interruption, especially with canagliflozin or severe vascular disease.
Investigation priorities
Confirm kidney indication, product eligibility and baseline risk.
Management branches
Type 2 diabetes, heart failure or CKD meets current NICE and licensed criteria.
- Confirm product-specific indication, eGFR, albuminuria, blood pressure, volume status, diabetes type, ketone risk, foot disease, genital infection history and pregnancy status.
- Reconcile diuretics, insulin and sulfonylureas, correcting volume depletion and avoiding abrupt insulin reduction; explain that kidney and heart benefit can exceed the glucose effect.
- Provide written DKA symptoms, blood-ketone, sick-day, fasting, surgery, genital hygiene and urgent perineal or foot warning advice before the first dose.
- Review renal function and tolerability at the locally specified interval, interpreting any early dip in the whole clinical context and preserving treatment when safely appropriate.