Insulin aspart

What it is used for

• Type 1 diabetes, as mealtime insulin or in an insulin pump
• Type 2 diabetes, when other treatments are not enough
• Diabetes in pregnancy

Read our guides:

• Type 1 diabetes
• Type 2 diabetes

Off-label uses

Doctors sometimes prescribe a medicine for a condition it is not officially licensed for. This is called off-label use. It is legal and common when there is good evidence it helps, and your doctor should explain why they are suggesting it.

Insulin aspart is not commonly used off-label.

How it works

Insulin is a hormone that moves sugar from the blood into the body's cells. Insulin aspart starts working within about 10 to 20 minutes and lasts 3 to 5 hours, covering the rise in blood sugar after a meal.

Side effects

Like all medicines, Insulin aspart can cause side effects, although not everyone gets them. Many are mild and ease after the first few weeks.

Common side effects

• low blood sugar (hypos)
• redness or swelling where you inject
• lumps under the skin if you inject in the same place
• weight gain

Tell your doctor or pharmacist if these bother you or do not go away.

Serious side effects

These are rare. Call 111 or contact your doctor straight away if you get:

• a severe hypo with confusion, fits or passing out. Someone should give glucagon or call 999
• swelling of the face or trouble breathing

Call 999 if you have signs of a serious allergic reaction, such as swelling of your lips, mouth, throat or tongue, or trouble breathing.

You can report any side effect to the Yellow Card scheme, run by the medicines regulator.

Stopping and withdrawal

Important safety information

• Learn the signs of a hypo and always carry fast-acting sugar.
• Rotate where you inject to avoid lumps.
• Tell the DVLA if you take insulin and drive.

Questions about your medicine?

A pharmacist can answer questions about your medicines for free, without an appointment. You can also ask your GP for a medication review. Check if you can get free prescriptions.