Paediatric Diabetes Medicines

Type 1 diabetes accounts for nearly all childhood diabetes and needs insulin from diagnosis for life. Type 2 diabetes is rising in obese adolescents and is treated with lifestyle change and metformin, with insulin if ketosis or severe hyperglycaemia is present. Education on injection, glucose monitoring, hypoglycaemia and sick days is part of every prescription.

Glycaemic targets. HbA1c under 7% (53 mmol/mol) with minimal hypoglycaemia. Pre-meal capillary glucose 4 to 8 mmol/L.

• Type 1, total daily insulin dose: 0.7 to 1 unit/kg/day before puberty, 1 to 1.5 units/kg/day during puberty, and under 0.5 unit/kg/day in the partial remission phase.
• Basal-bolus regimen: basal long-acting insulin about 40 to 50% of the daily dose once or twice daily, with rapid-acting insulin before meals. Starting insulin to carbohydrate ratio about 1 unit for each 10 to 15 g, and a correction of 1 unit lowering glucose by about 2 to 3 mmol/L, individualised by a specialist.
• Where only human insulin is available: neutral protamine insulin 0.5 to 1 unit/kg/day, two thirds before breakfast and one third before the evening meal, with soluble insulin 30 minutes before meals.
• Hypoglycaemia (glucose under 4 mmol/L): 10 to 20 g fast-acting carbohydrate (0.3 g/kg) orally and recheck in 15 minutes. Severe (unconscious or fitting): glucagon 0.5 mg (under 25 kg) or 1 mg intramuscularly, or 10% glucose 2 mL/kg intravenously.
• Diabetic ketoacidosis: isotonic fluid 10 mL/kg over 30 minutes only for shock, otherwise replace the deficit evenly over 48 hours. Start insulin at 0.05 to 0.1 unit/kg/h at least 1 hour after fluids begin, add potassium chloride 40 mmol/L to fluids once urine is passing and potassium is not raised, and do not give bicarbonate routinely. For suspected cerebral oedema: mannitol 0.5 to 1 g/kg or 3% sodium chloride 2.5 to 5 mL/kg over 10 to 15 minutes.
• Type 2: metformin 500 mg once daily with a meal, increased weekly to 1 g twice daily (maximum 2 g/day), from 10 years of age.

Sick days. Never stop basal insulin. Check glucose every 2 to 4 hours and ketones when glucose is over 14 mmol/L or the child is vomiting. Ketones over 1.5 mmol/L need extra rapid-acting insulin and urgent review.

Exercise. Reduce the bolus insulin or add carbohydrate before activity.

Kidney impairment. Insulin requirements fall. Metformin is avoided with an estimated glomerular filtration rate under 45 mL/min/1.73 m2 for starting, and stopped under 30.

Liver impairment. Reduce insulin and monitor for hypoglycaemia.

Special groups. Adolescents have higher insulin needs and risk of missed doses. Girls need pregnancy counselling. In East Africa, insulin storage without a refrigerator (clay pot cooling, away from sunlight) and needle reuse are practical problems, and limited access to glucose strips makes symptom awareness important.

Monitoring. Capillary glucose at least 4 times a day, HbA1c every 3 months, blood pressure yearly, urine albumin to creatinine ratio yearly from puberty or 5 years after diagnosis, eye screening from 11 to 12 years, and screening for thyroid disease and coeliac disease.

Referral and escalation. Refer all new diagnoses to a specialist team. Escalate for ketosis with vomiting, severe hypoglycaemia, HbA1c over 9%, and recurrent diabetic ketoacidosis.

Stopping. Do not stop insulin in type 1 diabetes. Metformin is stopped during acute illness with dehydration, contrast studies and surgery.