Biphasic insulin lispro

How it works

The rapid-acting lispro fraction controls post-meal glucose while the protaminated fraction provides a longer background effect; both lower blood glucose by enhancing cellular glucose uptake and reducing hepatic glucose production.

Prescribing in practice

• Hypoglycaemia is the principal hazard — the rapid component acts promptly, so the dose must be matched to meals and given in close relation to eating.
• Resuspend the cloudy suspension gently before each dose and never give it intravenously.
• Insulin requirements vary with illness, exercise, weight and renal function, and changes between insulin brands should be supervised.

Monitoring

Monitor capillary and longer-term blood glucose (HbA1c), injection sites and for hypoglycaemia, adjusting doses to meals and activity.

Counselling the patient

• Mix the pen until evenly cloudy and inject around mealtimes as directed.
• Know how to recognise and treat a hypo, and rotate injection sites.
• Never share pens or needles and review monitoring when unwell.

Evidence & guidelines

Premixed insulin lispro is supported by randomised trials showing effective control of post-prandial and overall glycaemia in diabetes.