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Educational draft · awaiting clinical reviewUse Rapid for revision, not patient-care decisions. Check current national and local guidance and the BNF or BNFC before acting.

Type 2 diabetes mellitus

Endocrinology and metabolism · UK scope · Sources checked 27 Aug 2026 · Clinical review pending

RapidFull
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Type 2 phenotype does not exclude insulin-deficient crisis

Marked hyperglycaemia with dehydration, confusion, vomiting, ketones, deep breathing or catabolic weight loss requires immediate DKA or HHS assessment. SGLT2 inhibitors can be associated with ketoacidosis despite a glucose value that is lower than expected, and intercurrent illness can rapidly change renal function and medicine safety.

Action: Use ABCDE, measure bedside glucose and blood ketones, obtain venous gas, electrolytes, renal function and osmolality where indicated, and follow the current JBDS-aligned local pathway. Withhold medicines inappropriate during acute dehydration or surgery according to the person's sick-day plan, but do not delay insulin when metabolic decompensation requires it.

Synopsis

Individualise type 2 diabetes care around glycaemia, cardiorenal protection, complications, treatment burden and acute safety using current UK pathways.

  • Type 2 diabetes is heterogeneous insulin resistance and beta-cell dysfunction; management should address cardiovascular, renal, metabolic and psychosocial risk rather than chase HbA1c alone.
  • At diagnosis, provide structured education, nutritional and activity support, smoking intervention and complication assessment alongside medicine discussion.
  • The current NICE NG28 pathway generally places modified-release metformin with an SGLT2 inhibitor at first line, with selection refined by established cardiovascular disease, heart failure, chronic kidney disease, frailty and contraindications.
  • Follow the current NICE visual summary and local formulary because cardiorenal pathways, licences, renal thresholds and cost-effective choices evolve faster than memory-based sequences.
  • Symptomatic marked hyperglycaemia or catabolism may require insulin or a sulfonylurea initially; review the need once glucose toxicity and the acute situation improve.
  • SGLT2 users need explicit ketoacidosis and sick-day education, including temporary interruption during major illness, fasting or surgery under the applicable pathway.
  • Set an individual HbA1c target that considers hypoglycaemia, frailty, comorbidity and preference, and intensify without therapeutic inertia when benefit outweighs burden.
  • Annual review integrates eyes, feet, kidneys, blood pressure, lipids, liver and cardiovascular status; remission does not erase surveillance or relapse risk.

Investigation priorities

01
HbA1c with glucose reviewFirst step

Measure chronic glycaemic exposure and support target setting when red-cell conditions make HbA1c reliable.

Management branches

FoundationStart integrated treatment

Type 2 diabetes is newly confirmed and there is no metabolic emergency.

  1. Assess symptoms, renal function, albuminuria, cardiovascular and heart-failure history, frailty, pregnancy potential, complications and the person's priorities.
  2. Offer structured education and tailored nutrition, activity and weight support, then select first-line medicines from the current NICE NG28 visual pathway and local formulary.
  3. Agree the aim and review point for each intervention, teach sick-day safety, arrange retinal and foot pathways, and address blood pressure, lipids and smoking concurrently.

Key medicines

Modified-release metforminStart at the locally recommended low oral dose with food and increase gradually to the tolerated effective regimen, adapting or stopping according to renal function and acute-illness guidance.Gastrointestinal effects and vitamin B12 deficiency occur. Avoid when severe renal or hypoxic illness raises lactic-acidosis risk, and apply current contrast, surgery and sick-day rules rather than a blanket permanent stop.
SGLT2 inhibitorUse the licensed once-daily preparation selected by the current NICE indication, eGFR, comorbidity and local formulary, with renal review before initiation and during significant illness.Discuss genital infection, volume depletion and euglycaemic DKA. Pause for major illness, fasting or surgery under the agreed pathway; recurrent ketosis, very low carbohydrate intake or severe insulin deficiency may make treatment unsuitable.
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Sources and review status5 sources · checked 27 Aug 2026 · clinical review pending+
Sources

Sources and review status

National guidance is shown before implementation-dependent detail. Typical adult dose examples remain subject to patient factors, contraindications and the live BNF or specialist protocol. Source check completed 27 Aug 2026; clinical approval remains outstanding.

  • NICE NG28 initial medicinesCurrent 2026 first-line and comorbidity-directed pharmacological recommendations.
  • NICE NG28 blood glucose managementHbA1c targets, monitoring and intensification principles.
  • NICE NG28 structured educationEducation and self-management support at diagnosis and review.
  • JBDS diabetic ketoacidosis guidanceRecognition and management of DKA including lower-glucose presentations.
  • NICE NG19 diabetic foot problemsFoot risk assessment and urgent active-foot pathways.

Editorial contact: Doctor’s Passport editorial team. Source-check date is separate from clinical approval. Report a content problem · Content changes

Authoring stateRapid draftClinical stateAwaiting reviewJurisdictionUnited Kingdom