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Type 2 Diabetes Mellitus

Also known as: T2DM · diabetes · high blood sugar · hyperglycaemia

Chronic hyperglycaemia from insulin resistance plus relative insulin deficiency — a major driver of cardiovascular, renal, eye and nerve disease.

Source · Reviewed 2026-08-15 · v1.0— AI-assisted draft — verify against the cited guideline before clinical use.

⚕️ Education only — not medical advice. Verify against the latest official guideline and your local protocol; confirm every drug dose against the cited source before clinical use.

Who gets it

Adults (and increasingly the young); risk rises with central obesity, family history, physical inactivity and South-Asian ethnicity (risk begins at a LOWER BMI). Prior gestational diabetes and PCOS add risk.

Red flags — escalate / refer

Vomiting, drowsiness, dehydration, deep sighing (Kussmaul) breathing or very high glucose → suspect DKA/HHS: a hyperglycaemic emergency → urgent referral.
Rapid weight loss, ketosis or lean young patient → consider type 1 diabetes / LADA rather than type 2.
Foot ulcer, spreading infection or rest pain → urgent diabetic-foot / vascular review.

Work-up / diagnosis

1Diagnose on any ONE (confirm on a separate day unless unequivocal symptoms + high glucose): fasting plasma glucose ≥126 mg/dL; 2-hour plasma glucose ≥200 mg/dL on 75 g OGTT; HbA1c ≥6.5%; or random plasma glucose ≥200 mg/dL with classic symptoms.
2At diagnosis, assess complications & CV risk: HbA1c, renal function (eGFR + urine albumin:creatinine), lipid profile, blood pressure, dilated fundus exam, and a foot examination.
3Record weight/BMI and waist circumference; ask about smoking.

Management — overview

Structured lifestyle for all: individualised diet, ≥150 min/week activity, weight loss, and tobacco cessation — the foundation of care.
Start metformin as first-line drug unless contraindicated, alongside lifestyle.
Set an individualised HbA1c target (generally <7%; looser for the elderly/comorbid, tighter for young/newly diagnosed if achieved safely).
Treat total cardiovascular risk: blood pressure and a statin as indicated — this reduces outcomes more than glucose alone.
Escalate by comorbidity: prefer an SGLT2 inhibitor or GLP-1 receptor agonist when there is established cardiovascular disease, heart failure or chronic kidney disease.
Screen for complications at least yearly (eye, foot, kidney).

In-depthFull dosing & advanced protocol

Drug dosing

Metformin (biguanide)

First-line glucose-lowering therapy

Adult dose: Start 500 mg once–twice daily with meals; titrate over weeks toward 1000 mg twice daily (usual max ~2 g/day)
Route: Oral
Population: Hold if eGFR <30 mL/min/1.73m²; review at 30–45

Caution: GI upset (use extended-release if needed); withhold during acute illness, contrast, or dehydration.

ICMRStandard Treatment Workflows (STWs), India — Dept. of Health Research & ICMR (2022+) ↗

Gliclazide (sulfonylurea)

Add-on when metformin insufficient (cost-effective)

Adult dose: 40–80 mg once daily, titrated (modified-release 30–120 mg OD)
Route: Oral

Caution: Hypoglycaemia and weight gain — caution in the elderly and in renal impairment.

WHOWHO Model List of Essential Medicines (electronic EML) (2025 (24th)) ↗

Empagliflozin (SGLT2 inhibitor)

Preferred add-on with ASCVD, heart failure or CKD

Adult dose: 10 mg once daily
Route: Oral

Caution: Genital mycotic infections, volume depletion; rare euglycaemic DKA — hold when acutely unwell.

WHOWHO Model List of Essential Medicines (electronic EML) (2025 (24th)) ↗

Individualising the target & second-line choice

Tighter HbA1c (≈6.5%) for young, newly-diagnosed patients if reached without hypoglycaemia; looser (7.5–8%) for frail/elderly or limited life expectancy.
Choose the second drug by comorbidity: SGLT2i (HF/CKD), GLP-1RA (ASCVD/obesity), DPP-4i (weight-neutral, well-tolerated), sulfonylurea (low cost), insulin when very high glucose or symptomatic.
Start insulin without delay if markedly symptomatic, HbA1c very high, or during acute illness/pregnancy.

ICMRStandard Treatment Workflows (STWs), India — Dept. of Health Research & ICMR (2022+) ↗

Sick-day rules & complication screening

During acute illness, temporarily stop drugs that risk harm when dehydrated (metformin, SGLT2i, ACEi/ARB, diuretics, NSAIDs); maintain hydration and monitor glucose/ketones.
Annual review: dilated retinal exam, foot exam (sensation + pulses), urine ACR + eGFR, lipids and blood pressure.

References

Guidelines change. If something here is out of date, tell us — we keep these current.

🚩 Report outdated / suggest update

More protocols

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Type 2 Diabetes Mellitus

Also known as: T2DM · diabetes · high blood sugar · hyperglycaemia

Chronic hyperglycaemia from insulin resistance plus relative insulin deficiency — a major driver of cardiovascular, renal, eye and nerve disease.

Source · Reviewed 2026-08-15 · v1.0— AI-assisted draft — verify against the cited guideline before clinical use.

Red flags — escalate / refer

Vomiting, drowsiness, dehydration, deep sighing (Kussmaul) breathing or very high glucose → suspect DKA/HHS: a hyperglycaemic emergency → urgent referral.

Rapid weight loss, ketosis or lean young patient → consider type 1 diabetes / LADA rather than type 2.

Foot ulcer, spreading infection or rest pain → urgent diabetic-foot / vascular review.

Work-up / diagnosis

1Diagnose on any ONE (confirm on a separate day unless unequivocal symptoms + high glucose): fasting plasma glucose ≥126 mg/dL; 2-hour plasma glucose ≥200 mg/dL on 75 g OGTT; HbA1c ≥6.5%; or random plasma glucose ≥200 mg/dL with classic symptoms.

2At diagnosis, assess complications & CV risk: HbA1c, renal function (eGFR + urine albumin:creatinine), lipid profile, blood pressure, dilated fundus exam, and a foot examination.

3Record weight/BMI and waist circumference; ask about smoking.

Management — overview

Structured lifestyle for all: individualised diet, ≥150 min/week activity, weight loss, and tobacco cessation — the foundation of care.

Start metformin as first-line drug unless contraindicated, alongside lifestyle.

Set an individualised HbA1c target (generally <7%; looser for the elderly/comorbid, tighter for young/newly diagnosed if achieved safely).

Treat total cardiovascular risk: blood pressure and a statin as indicated — this reduces outcomes more than glucose alone.

Escalate by comorbidity: prefer an SGLT2 inhibitor or GLP-1 receptor agonist when there is established cardiovascular disease, heart failure or chronic kidney disease.

Screen for complications at least yearly (eye, foot, kidney).

Drug dosing

Metformin (biguanide)

First-line glucose-lowering therapy

Adult dose: Start 500 mg once–twice daily with meals; titrate over weeks toward 1000 mg twice daily (usual max ~2 g/day)
Route: Oral
Population: Hold if eGFR <30 mL/min/1.73m²; review at 30–45

Caution: GI upset (use extended-release if needed); withhold during acute illness, contrast, or dehydration.

ICMRStandard Treatment Workflows (STWs), India — Dept. of Health Research & ICMR (2022+) ↗

Gliclazide (sulfonylurea)

Add-on when metformin insufficient (cost-effective)

Adult dose: 40–80 mg once daily, titrated (modified-release 30–120 mg OD)
Route: Oral

Caution: Hypoglycaemia and weight gain — caution in the elderly and in renal impairment.

WHOWHO Model List of Essential Medicines (electronic EML) (2025 (24th)) ↗

Empagliflozin (SGLT2 inhibitor)

Preferred add-on with ASCVD, heart failure or CKD

Adult dose: 10 mg once daily
Route: Oral

Caution: Genital mycotic infections, volume depletion; rare euglycaemic DKA — hold when acutely unwell.

WHOWHO Model List of Essential Medicines (electronic EML) (2025 (24th)) ↗

Individualising the target & second-line choice

Tighter HbA1c (≈6.5%) for young, newly-diagnosed patients if reached without hypoglycaemia; looser (7.5–8%) for frail/elderly or limited life expectancy.

Choose the second drug by comorbidity: SGLT2i (HF/CKD), GLP-1RA (ASCVD/obesity), DPP-4i (weight-neutral, well-tolerated), sulfonylurea (low cost), insulin when very high glucose or symptomatic.

Start insulin without delay if markedly symptomatic, HbA1c very high, or during acute illness/pregnancy.

👤 Who gets it

🚩 Red flags — escalate / refer

🔎 Work-up / diagnosis

🧭 Management — overview

💊 Drug dosing

Metformin (biguanide)

Gliclazide (sulfonylurea)

Empagliflozin (SGLT2 inhibitor)

📈 Individualising the target & second-line choice

📈 Sick-day rules & complication screening

📚 References

More protocols

👤 Who gets it

🚩 Red flags — escalate / refer

🔎 Work-up / diagnosis

🧭 Management — overview

💊 Drug dosing

Metformin (biguanide)

Gliclazide (sulfonylurea)

Empagliflozin (SGLT2 inhibitor)

📈 Individualising the target & second-line choice

📈 Sick-day rules & complication screening

📚 References

More protocols

Who gets it

Red flags — escalate / refer

Work-up / diagnosis

Management — overview

Drug dosing

Individualising the target & second-line choice

Sick-day rules & complication screening

References

Who gets it

Red flags — escalate / refer

Work-up / diagnosis

Management — overview

Drug dosing

Individualising the target & second-line choice

Sick-day rules & complication screening

References