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Antidiabetic / short-acting and intermediate-acting insulin

Human insulin: uses, side effects & precautions

Also known as Actrapid, Humulin R, Humulin N, Insulatard, Novolin, Humulin M3, Mixtard.

Ces informations sont fournies à titre indicatif uniquement et ne constituent pas un avis médical. Consultez toujours un professionnel de santé qualifié pour toute préoccupation médicale personnelle. En cas d'urgence, appelez votre numéro d'urgence local.

What it is used for

  • Type 1 diabetes
  • Type 2 diabetes when insulin is needed
  • Diabetes in hospital and emergency settings (regular insulin)

How it works

Human insulin replaces or supplements the body's own insulin so that cells can take in glucose. 'Regular' (soluble) human insulin is short-acting for meals, while NPH/isophane is intermediate-acting for background coverage; premixed versions combine both.

How it is taken

Given as an injection under the skin using a pen, vial and syringe; regular insulin can also be used in hospital by drip under supervision. It is taken around meals and/or as background insulin as prescribed. Use exactly as your diabetes team shows you and as the label directs; rotate sites and never share pens or needles.

No doses here on purpose. The right strength and schedule depend on you — only a doctor or pharmacist should set them. Always follow your prescription and the label.

Common side effects

  • Low blood sugar (hypoglycaemia)
  • Injection-site reactions (redness, itching, swelling)
  • Skin lumps or thickening with repeated use of one spot
  • Weight gain

Serious effects — get help

  • Severe low blood sugar with confusion, seizures, or loss of consciousness — emergency care needed
  • Severe allergic reaction
  • Very low potassium (uncommon) causing weakness or irregular heartbeat

If a reaction is severe — for example trouble breathing, swelling of the face or throat, or collapse — go to the nearest emergency room now or call your local emergency number. Do not wait for an online consultation.

Interactions to watch

  • Other diabetes medicines and insulins
  • Alcohol
  • Steroids and some hormone or blood-pressure medicines
  • Beta-blockers (may mask low-blood-sugar warning signs)

Who should take care

  • Cloudy (NPH/premixed) insulins usually need gentle mixing before use — follow your label
  • Learn to treat low blood sugar and carry a fast-acting sugar source
  • Adjust care for illness, exercise, and meal changes with your team
  • Tell your care team if pregnant, breastfeeding, or planning pregnancy
  • Store and handle the insulin exactly as directed

Frequently asked questions

What is the difference between regular and NPH insulin?
Regular (soluble) insulin is short-acting and covers meals; NPH (isophane) is intermediate-acting and gives background coverage. Premixed insulins combine both in fixed amounts.
Why is some insulin cloudy?
NPH and premixed insulins are normally cloudy and need gentle mixing before injecting. Clear insulins like regular should not be cloudy — check your label.
How does this compare to newer analogue insulins?
Human insulins work well but act slightly slower or differently than newer analogue insulins. Your doctor chooses the type that fits your routine and needs.
What should I do when I'm unwell?
Illness can change your blood sugar and insulin needs. Follow your sick-day plan and contact your diabetes team if you cannot keep food or fluids down.
Is Human insulin safe to take?
For most people it is safe when taken exactly as a doctor or pharmacist advises and as printed on the label. Tell your clinician about your other medicines and health conditions, and seek urgent care for any serious reaction.

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