Insulin
Also known as: NovoRapid, Humalog, Lantus, Levemir, Tresiba, Humulin, NovoMix
What it's for
Insulin lowers blood sugar in diabetes. It replaces or supplements the insulin your body cannot make. Different types work for different lengths of time.
Comes as: Injection (pen, pump, or syringe)
How to take it
- Dose is individual - your diabetes team will advise.
- Rapid-acting: Take just before or with meals.
- Long-acting: Usually once or twice daily at the same time.
- Inject into stomach, thighs, or upper arms. Rotate sites.
Doses here are typical. Always follow the instructions from your prescriber or on the packet — they come first.
Common side effects
- Low blood sugar (hypoglycaemia) - very important to recognise
- Weight gain
- Injection site reactions (redness, swelling)
- Lipohypertrophy (fatty lumps from injecting in same spot)
The leaflet inside the packet lists all known side effects.
Important safety points
- Always carry hypo treatment (glucose tablets or sugary drink)
- Know the signs of low blood sugar: sweating, shaking, hunger, confusion
- Rotate injection sites to prevent lumps
- Store correctly - check the instructions for your insulin type
Get medical help urgently if…
- Severe low blood sugar - confusion, loss of consciousness, seizures - give glucagon if available and call 999
- You cannot eat or keep food down
- Signs of diabetic ketoacidosis: vomiting, stomach pain, fruity breath, drowsiness
- You have given too much insulin
Call NHS 111 for urgent advice, or 999 if someone is seriously unwell.
Before you act on anything here
This page is general information, written to help you understand — it is not personal medical advice and it cannot tell you what is right for you. Talk to your own GP, pharmacist or nurse about your own health.
- Need help now but it's not an emergency? Call NHS 111 or use 111.nhs.uk.
- Emergency? Call 999 or go to A&E.