Rapid-Acting Insulin Analogue (Bolus) Pregnancy: Can be used during pregnancy; intensified blood-glucose control and monitoring recommended (insulin requirements usually fall in the first trimester and rise during the second and third). No restrictions during breast-feeding.

Insulin Aspart

Brand names: NovoRapid, Fiasp (faster-acting)

Insulin aspart is a rapid-acting insulin analogue used at mealtimes to control postprandial glucose, in basal-bolus regimens, pumps and intravenously in specialist settings.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Individualised. Total daily insulin requirement (adults and children) is usually 0.5-1.0 unit/kg/day; in a basal-bolus regimen 50-70% is provided by insulin aspart (mealtime bolus) and the remainder by intermediate- or long-acting insulin

Route: Subcutaneous injection (abdominal wall, thigh, upper arm, deltoid or gluteal region); may also be given by continuous subcutaneous infusion (pump) or intravenously by healthcare professionals using a vial

Frequency: Immediately before a meal (may be given soon after a meal when necessary); onset of action within 10-20 minutes, duration 3-5 hours

Rapid-acting insulin analogue; potency expressed in units. Normally used in combination with intermediate- or long-acting insulin. Rotate injection sites within the same region to reduce lipodystrophy/cutaneous amyloidosis. Dose adjustment may be needed with increased physical activity, dietary change or concomitant illness. Elderly and renal or hepatic impairment: intensify glucose monitoring and adjust dose individually. Can be used in children and adolescents from 1 year of age; safety and efficacy below 1 year not established. FlexPen delivers 1-60 units in 1-unit increments (subcutaneous use only).

Dose adjustments

Renal

Renal or hepatic impairment may reduce insulin requirements; intensify glucose monitoring and adjust the dose on an individual basis.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to insulin aspart or to any excipient

Side effects

Hypoglycaemia (most frequently reported)
Injection-site reactions (pain, redness, hives, inflammation, bruising, swelling, itching) - usually transitory
Lipodystrophy and cutaneous amyloidosis at injection sites
Allergic reactions: urticaria, rash, eruptions (uncommon); rarely systemic hypersensitivity/anaphylactic reactions
Transient refraction anomalies and oedema at the start of treatment

Interactions

Drugs that may increase hypoglycaemia risk: oral antidiabetic agents, ACE inhibitors, angiotensin II receptor blockers, disopyramide, fibrates, fluoxetine, MAO inhibitors, pentoxifylline, pramlintide, salicylates, octreotide, sulfonamide antibiotics
Drugs that may reduce the glucose-lowering effect: corticosteroids, diuretics, danazol, oestrogens and oral contraceptives, thyroid hormones, growth hormone (somatropin), sympathomimetics, atypical antipsychotics (olanzapine, clozapine), protease inhibitors, isoniazid, niacin, glucagon

Clinical monograph

How it works

Modification of the insulin molecule speeds dissociation into monomers after injection, giving faster onset and shorter duration than soluble human insulin.

Prescribing in practice

Hypoglycaemia is the key risk; its rapid onset means it should generally be given just before or with food to match absorption.
As a high-alert medicine, prescribe units in words and specify the exact product and device to prevent errors.
Adjust timing and amount in renal or hepatic impairment and during changes in food intake or activity.

Monitoring

Monitor capillary blood glucose and HbA1c, paying particular attention to postprandial readings and hypoglycaemia.

Counselling the patient

Inject just before eating because it works quickly.
Carry fast-acting carbohydrate and know how to treat a hypo.
Rotate injection sites and never share your pen or needles.

Evidence & guidelines

Rapid-acting analogues improve postprandial control versus soluble human insulin and are widely recommended in diabetes guidance.

Reference: NICE NG17; ADA Diabetes Standards 2024; NovoRapid SPC; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways