Type 2 Diabetes Initial Management
Start metformin 500 mg daily at or soon after diagnosis, concurrently with lifestyle modifications including nutrition therapy and physical activity, increasing by 500 mg every 1-2 weeks up to 2000 mg daily in divided doses. 1, 2
When to Start Insulin Instead of Metformin
Do not start with metformin if the patient presents with any of the following—these require immediate insulin therapy: 1
- Ketosis or diabetic ketoacidosis 3, 1
- Random blood glucose ≥250 mg/dL 3, 1
- HbA1c >9% 3, 1
- Severe hyperglycemia with catabolism 1
- Symptomatic diabetes with polyuria, polydipsia, and weight loss 1
For patients requiring initial insulin, this allows quicker restoration of glycemic control and may allow β-cells to "rest and recover." Many can be weaned gradually from insulin and subsequently managed with metformin and lifestyle modification. 3
Metformin Dosing Protocol
- Start at 500 mg once daily 1, 2
- Increase by 500 mg every 1-2 weeks 3, 1
- Target dose: 2000 mg daily in divided doses 3, 1
- Take without regard to meals 4
The main gastrointestinal adverse effects (abdominal pain, bloating, loose stools) present at initiation are often transient. 3
Essential Lifestyle Modifications
Weight Loss Target
- Aim for at least 5% body weight loss if overweight or obese 1, 2
- Individualized medical nutrition therapy should be provided by a registered dietitian 2
- Diet should be culturally appropriate and sensitive to the patient's resources 2
Physical Activity
- Regular physical activity reduces HbA1c by 0.4% to 1.0% 5
- Physical activity also improves cardiovascular risk factors including hypertension and dyslipidemia 5
Monitoring Schedule
- HbA1c every 3 months until target is reached 1, 2
- Then HbA1c at least twice yearly once at target 1, 2
- Intensify treatment if glycemic targets are not met within 3 months 2
- Self-monitoring of blood glucose should be carried out regularly 2
When to Add Second-Line Agents
If metformin plus lifestyle modifications fail to achieve glycemic targets after 3 months, add a second agent. 1 Selection should prioritize: 1, 5
GLP-1 receptor agonists or SGLT2 inhibitors for patients with cardiovascular disease, kidney disease, or high cardiovascular risk 5
Other second-line options include: 1
- Sulfonylureas
- Thiazolidinediones (pioglitazone 15-45 mg daily) 4
- DPP-4 inhibitors
When to Start Insulin Therapy
- When triple therapy fails to achieve glycemic targets 1
- Start with basal insulin at 0.5 units/kg/day 1
- Titrate every 2-3 days based on blood glucose monitoring 1
- Add prandial insulin if glycemic targets still not met with escalating basal insulin doses 1
- Approximately one-third of patients with type 2 diabetes require insulin during their lifetime 5
Critical Pitfalls to Avoid
- Clinical inertia—delaying treatment intensification when glycemic targets are not met 1
- Failing to assess cardiovascular and kidney risk factors at diagnosis 2
- Not adjusting medications during acute illness or procedures 1
- Missing the opportunity for early SGLT2i or GLP-1RA therapy in high-risk patients 5
Multidisciplinary Team Approach
Essential team members include: 2
- Physician
- Diabetes nurse educator
- Registered dietitian
- Mental health professional
Long-Term Benefits of Intensive Control
Intensive glucose-lowering strategies (HbA1c <7%) versus conventional treatment show absolute reductions in: 5
- Microvascular disease: 3.5% (retinopathy, nephropathy)
- Myocardial infarction: 3.3-6.2%
- Mortality: 2.7-4.9%
These benefits persist 2 decades after trial completion. 5