I am an adult newly diagnosed with type 2 diabetes; what initial assessments and first‑line treatment should I start?

Initial Management of Newly Diagnosed Type 2 Diabetes in Adults

Start metformin 500 mg once or twice daily with meals immediately at diagnosis, and if your A1C is ≥9%, add basal insulin 10 units daily (or 0.1–0.2 units/kg/day) on the same day. 1

Immediate First Steps at Diagnosis

Essential Laboratory Workup

Before or at your first treatment visit, obtain these baseline tests:

• HbA1c to confirm diagnosis (≥6.5% is diagnostic) and establish baseline glycemic control 2
• Fasting plasma glucose if HbA1c wasn't the initial diagnostic test 2
• Urine albumin-to-creatinine ratio (UACR) using a random spot collection to screen for kidney disease 2
• Serum creatinine with calculated eGFR to assess kidney function and stage any chronic kidney disease 2
• Serum potassium as baseline, particularly before starting certain medications 2
• Complete lipid profile (LDL, HDL, total cholesterol, triglycerides) to determine cardiovascular risk and need for statin therapy 2
• Blood pressure measurement at every visit to screen for hypertension 2, 3

Mandatory Specialist Referrals at Diagnosis

• Comprehensive dilated eye examination by an ophthalmologist or optometrist shortly after diagnosis—up to 30% of type 2 diabetes patients already have retinopathy at diagnosis, and 3% have sight-threatening complications requiring immediate intervention 4, 2
• Comprehensive foot examination including inspection, foot pulses, and testing for loss of protective sensation using 10-g monofilament, 128-Hz tuning fork vibration testing, pinprick sensation, ankle reflexes, or vibration perception threshold 2

First-Line Pharmacologic Treatment

For A1C <9% (Metabolically Stable)

Start metformin monotherapy as the initial pharmacologic treatment if renal function is >30 mL/min/1.73 m² 4, 5:

• Begin with 500 mg once daily with dinner or 500 mg twice daily with meals to minimize gastrointestinal side effects 1
• Increase by 500 mg weekly as tolerated until reaching the target dose of 2000 mg daily (1000 mg twice daily) 1
• Metformin typically reduces A1C by 1–2% 1

For A1C ≥9% (Marked Hyperglycemia)

Initiate dual therapy immediately with both metformin AND basal insulin rather than metformin alone, because metformin monotherapy will leave you well above goal 4, 1:

• Start metformin as described above 1
• Simultaneously start basal insulin at 10 units daily or 0.1–0.2 units/kg/day 1
• Increase insulin by 2 units every 3 days until fasting plasma glucose reaches 80–130 mg/dL 1
• Basal insulin analogues are strongly preferred over NPH insulin due to significantly reduced risk of hypoglycemia, particularly nocturnal hypoglycemia 1

For A1C ≥10% or Blood Glucose ≥250 mg/dL with Symptoms

If you present with marked hyperglycemia (blood glucose ≥250 mg/dL), A1C ≥8.5%, or symptoms of hyperglycemia (polyuria, polydipsia, nocturia, weight loss), start basal insulin immediately while initiating metformin 4:

• This applies even more urgently at A1C ≥10% due to evidence of ongoing catabolism 4, 1
• If ketosis or ketoacidosis is present, insulin is mandatory until glycemia normalizes 4

Special Considerations for Patients with Comorbidities

If You Have Heart Failure (Reduced or Preserved Ejection Fraction)

Add an SGLT2 inhibitor for glycemic management and prevention of heart failure hospitalizations, regardless of baseline A1C 4

If You Have Chronic Kidney Disease (eGFR 20–60 mL/min/1.73 m² and/or Albuminuria)

Add an SGLT2 inhibitor to minimize CKD progression, reduce cardiovascular events, and reduce heart failure hospitalizations (though glycemic benefits diminish at eGFR <45 mL/min/1.73 m²) 4

If You Have Advanced CKD (eGFR <30 mL/min/1.73 m²)

A GLP-1 receptor agonist is preferred for glycemic management due to lower hypoglycemia risk and cardiovascular event reduction 4

If You Have or Are at High Risk for Cardiovascular Disease

Prioritize adding an SGLT2 inhibitor or GLP-1 receptor agonist with proven cardiovascular benefit early in your treatment course 1, 5

Monitoring and Titration

During Initial Insulin Titration

• Check fasting blood glucose daily to guide insulin dose adjustments 1
• Recheck A1C in 3 months to assess response to therapy 1
• Monitor for hypoglycemia symptoms and provide education on recognition and treatment with 15–20 grams of fast-acting carbohydrate 1

If A1C Remains >7% After 3 Months on Metformin Plus Basal Insulin

Add a GLP-1 receptor agonist as the preferred next step due to efficacy and lower risk of hypoglycemia and weight gain 1:

• Alternatively, consider adding prandial insulin 1
• For patients with established atherosclerotic cardiovascular disease or heart failure, adding an SGLT2 inhibitor or GLP-1 receptor agonist with proven cardiovascular benefit is strongly recommended 1

Ongoing Monitoring Schedule

• A1C every 3 months if therapy has been altered or targets are not being met; at least twice yearly if targets are met 3
• Annual screening for UACR, serum creatinine/eGFR, comprehensive eye examination, foot examination, and lipid profile 2
• More frequent monitoring if abnormalities detected: eGFR every 3–6 months if stage 3–4 CKD, eye exams every 3–12 months if retinopathy present 2

Essential Patient Education

Medication Management

• Proper insulin injection technique and systematic rotation of injection sites 1
• Hypoglycemia recognition and treatment: symptoms include shakiness, sweating, confusion; treat with 15–20 grams of fast-acting carbohydrate 1
• Medication adherence and the importance of not missing doses 1

Lifestyle Modifications

• Refer to diabetes self-management education and support (DSMES) services for comprehensive care 1
• Physical activity can reduce A1C by 0.4–1.0% and improve cardiovascular risk factors 5
• Weight management is important, though no specific diet has proven most effective for health outcomes 5

Critical Pitfalls to Avoid

• Do not delay starting metformin at diagnosis—early combination therapy shortens time to glycemic goal attainment 4
• Do not start with metformin monotherapy alone if A1C ≥9%—you will leave the patient dangerously hyperglycemic for months 1
• Do not use NPH insulin when basal insulin analogues are available due to higher hypoglycemia risk 1
• Do not delay modification of treatment if individualized targets are not being met 3
• Do not overlook cardiovascular and kidney comorbidities—these mandate specific medication choices (SGLT2 inhibitors or GLP-1 receptor agonists) regardless of A1C 4, 1