Clinical frontline
Practical clinical guidance for family physicians, starting with rational insulin initiation.
A Practical Guide for Family Physicians
Why this topic matters
Type 2 diabetes has become one of the biggest healthcare challenges we face in Bangladesh, and family physicians are usually the first and most consistent point of contact for people living with it. Oral medications work well for a lot of patients, but a fair number will eventually need insulin to get their glucose under control.
The trouble is, insulin often gets started too late. Clinical inertia — that delay in starting or stepping up therapy even when it's clearly indicated — is a real problem, and it usually comes down to fear of injections, worry about hypoglycaemia or weight gain, and a lack of confidence on both sides of the consultation. Starting insulin at the right time can improve glucose control quickly, reduce glucotoxicity, protect remaining β-cell function, and prevent complications down the line. Family physicians are well placed to start and monitor insulin safely right in primary care.
When should you start insulin?
Immediate insulin initiation — newly diagnosed T2DM with severe hyperglycaemia: HbA1c ≥10%, random blood glucose ≥300 mg/dL (16.7 mmol/L), symptomatic hyperglycaemia, significant weight loss, or ketonuria/ketosis.
Consider basal insulin when, despite optimal oral therapy for 3–6 months: HbA1c remains above the individualized target (generally >7%), fasting glucose stays above 150–180 mg/dL, β-cell failure is progressing, or there's a contraindication or intolerance to oral agents.
Temporary insulin may be needed for severe infection, acute MI, stroke, major surgery, pregnancy, or high-dose steroid therapy.
Choosing the first insulin
For most adults with Type 2 diabetes, once-daily basal insulin is the preferred starting point — glargine, degludec, detemir, or NPH as a more cost-effective option. It's simple, safe, effective, and generally the easiest for patients to accept.
Stepwise algorithm for insulin initiation
Diagnosed Type 2 Diabetes → lifestyle modification + metformin → add a second/third oral agent or a GLP-1RA/SGLT2i as appropriate → is HbA1c above target after 3–6 months? If yes, assess the indication for insulin → start basal insulin at 10 units/day or 0.1–0.2 units/kg/day → patient monitors fasting glucose → adjust the dose every 3–4 days → target fasting glucose 80–130 mg/dL → is HbA1c at target? If yes, continue. If no, evaluate adherence, injection technique, and lifestyle, then either add prandial insulin or consider a fixed-ratio regimen.
Basal insulin titration
Start at 10 units once daily, or 0.1–0.2 units/kg/day, and adjust every 3–4 days. Simple titration like this tends to build patient confidence as much as it improves glucose control.
Patient education before starting insulin
Don't prescribe insulin without walking the patient through it first. Cover why insulin is needed, injection technique, how to store it, rotating injection sites, recognizing hypoglycaemia, self-monitoring blood glucose, sick-day rules, diet and exercise, and travel advice. A patient who understands their insulin sticks with it — that education is often what makes the difference.
Case discussion
Mr. Rahman, a 58-year-old businessman, has had Type 2 diabetes for 10 years. He's on metformin 1000 mg twice daily, empagliflozin 25 mg daily, and sitagliptin 100 mg daily. His HbA1c comes back at 9.6%, fasting glucose at 198 mg/dL, BMI 28 kg/m², eGFR 78 mL/min, with no history of hypoglycaemia.
Management: continue the metformin and empagliflozin, start basal insulin glargine at 10 units at bedtime, and advise home fasting glucose monitoring with the dose increasing by 2 units every 3 days until fasting glucose reaches 80–130 mg/dL. Review after two weeks, repeat HbA1c after three months. Three months later, his HbA1c had dropped to 7.2%, with no hypoglycaemia and noticeably better energy and confidence.
Common mistakes to avoid
Waiting too long to start insulin. Stopping metformin unnecessarily. Increasing the insulin dose too fast. Ignoring the patient's fasting glucose records. Skipping injection-technique teaching. Neglecting hypoglycaemia education. Intensifying therapy without first checking adherence and lifestyle.
Clinical pearls
Start with one injection and keep it simple — basal insulin alone is usually enough at first. Start low and titrate slowly. Continue metformin unless it's contraindicated. Consider SGLT2 inhibitors and GLP-1 receptor agonists where appropriate, especially for patients with cardiovascular disease, heart failure, CKD, or obesity. Individualize HbA1c targets based on age, comorbidities, life expectancy, and hypoglycaemia risk. Teach the 15-15 rule for hypoglycaemia — 15 g of fast-acting carbohydrate, then recheck glucose after 15 minutes. And remember: every insulin prescription needs education, follow-up, and dose titration alongside it, not just the prescription itself.
Key take-home messages
Insulin should be started based on clinical need, not delayed out of fear or misconception. Once-daily basal insulin is the right starting point for most adults with Type 2 diabetes in primary care. Structured titration and patient education matter just as much as the prescription itself. Family physicians play a genuinely pivotal role here — timely insulin initiation and steady follow-up prevent complications and meaningfully improve quality of life.
SFMB clinical practice tip: don't ask "Has the patient failed oral therapy?" Ask instead, "What is the safest and most effective next step for this patient today?"