Aldesleukin (IL-2, Proleukin or interleukin 2)

Aldesleukin is an immunotherpay drug. It is also known as interleukin 2 (IL-2) or by its brand name Proleukin.

It is a treatment for kidney cancer that has spread to another part of the body (advanced kidney cancer). It is also used in clinical trials for other types of cancer. 

How it works

Aldesleukin is a man made protein. It is very similar to a protein produced by the body called interleukin-2 (IL-2). Interleukin-2 is part of the immune system. It triggers certain white blood cells in the body called lymphocytes, which fight diseases and infections. 

Aldesleukin works in a number of ways. It:

  • works directly on cancer cells by interfering with how the cells grow and multiply
  • stimulates the immune system by encouraging the growth of killer T cells and other cells that attack cancer cells
  • encourages cancer cells to send out chemicals that attract immune system cells

How you have it

You usually have adesleukin as an injection just under the skin. You can also have it as a drip into your bloodstream (intravenous). 

Injection just under the skin

You usually have injections under the skin (subcutaneous injection) into the stomach, thigh or top of your arm.

You might have stinging or a dull ache for a short time after this type of injection but they don't usually hurt much. The skin in the area may go red and itchy for a while.

Into your bloodstream


  • central line
  • PICC line
  • portacath


When you have it

You have aldesleukin as cycles of treatment. This means that you have the drug and then a rest to allow your body to recover.

You usually have a daily injection under the skin for 5 days then 2 days rest. You have it like this for 4 weeks and then have a week without treatment. Then this 5 week cycle is repeated. The number of cycles of treatment you need depends on how well your cancer responds.

You might have aldesleukin as a continuous drip into a vein for 5 days. This means you will need to stay in hospital. The team caring for you can keep a close eye on how you are coping with it. 



Side effects


When to contact your team


  • you have severe side effects 
  • your side effects aren’t getting any better
  • your side effects are getting worse

Early treatment can help manage side effects better. 



Common side effects


Increased risk of infection



Breathlessness and looking pale


Increased risk of bruising and bleeding


Low levels of thyroid hormones (hypothyroidism)


Less common you might have higher levels of thyroid hormones (hyperthyroidism). You may lose weight or feel hot, anxious or hyperactive.

Loss of appetite


Less common you might also loss your sense of taste. 

Confusion, anxiety or depression

You might have some mood changes while having this drug. Let your doctor or nurse know if you feel anxious or depressed.

Less common you might feel agitated and irritable. You might also have hallucinations. 

Difficulty sleeping

It can help to change a few things about how you try to sleep. Try to go to bed and get up at the same time each day and spend some time relaxing before you go to bed. Some light exercise each day may also help. 

Or you might feel very tired and drowsy.

Dizziness and headaches


Less common you might also have fainting episodes. 

Numbness and tingling of the fingers and toes


Changes to how your heart works

You may get heart problems, such as angina, heart failure or a heart attack. You will have regular heart checks during and after the treatment. Tell your doctor or nurse straight away if you have any chest pain.

Your heart beat might not beat regularly or it might become faster. 

Low blood pressure


Less common you might get high blood pressure.

Feeling or being sick






Less common you might have constipation. Tell your healthcare team if you do. 

Sore, inflamed mouth



Skin problems





Let your healthcare team know if you are sweating much more than normal.


  • Cut out coffee, tea and nicotine.
  • Cut down on alcohol.
  • Sip cold or iced drinks.
  • Wear layers of light clothing so you can take clothes off if you overheat.
  • Have layers of bedclothes to remove as you need to.
  • Wear natural fibres such as silk or cotton instead of man made fabrics.

Muscle or joint pain


Passing less urine

You might pass less urine than usual. Tell your doctor or nurse if this happens.

Less common there might be blood in your urine. Tell your doctor or nurse if the colour of your urine is red to pinkish.

Changes to the way your liver works


Soreness, swelling or pain where you have the drug

The injection or infusion site where you have aldesleukin might become red, sore, painful or swollen. Tell your nurse or doctor straight away if this happens. 

High temperature (fever)


You might or might not have chills as well. 

Less common you might feel like you have the flu. 

Tiredness (fatigue)

You might feel very tired and as though you lack energy.


Weight gain or loss

You might gain or loss weight while having this treatment. 


You might have swelling while having this treatment. 

Difficulty breathing and coughing

You might develop a cough or breathing problems. This could be due to infection, such as pneumonia or inflammation of the lungs (pneumonitis). Let your doctor or nurse know straight away if you suddenly become breathless or develop a cough.

Changes to how your kidneys work


Occasional side effects


  • a serious reaction to an infection (sepsis) signs can include feeling very unwell, not passing urine, being sick, a very high or very low temperature or shivering - contact your advice line straight away if you have any of these symptoms
  • blood clots throughout your body in the small blood vessels if you have bleeding, bruising, a drop in blood pressure, shortness of breath, confusion or memory loss contact your healthcare helpline or healthcare team straight away
  • nose, throat or chest infection
  • changes to the minerals, salts and sugar in your blood such as a high levels of glucose, potassium or calcium or low levels of sodium or phosphate
  • not enough fluid in your body (dehydration)
  • nerve pain
  • problems with how you speak and talk
  • sore, red and watery eyes (conjunctivitis)
  • inflamed, congested and runny nose
  • difficulty swallowing
  • hair loss
  • hives
  • high levels of acid in the body – symptoms might include changes to your breathing, confusion, headaches, sleepiness and yellowing of the skin and whites of the eyes

Rare side effects


  • an allergic reaction that can cause a rash, shortness of breath, redness or swelling of the face and dizziness - some allergic reactions can be life-threatening alert your nurse or doctor if notice any of these symptoms
  • a low level of sugar (glucose) in the blood
  • fits (convulsions) or stiffness (paralysis)
  • inflammation of the pancreas
  • blockage of the gut and bowels
  • loss of colour to areas of the skin (vitiligo)

Coping with side effects


What else do I need to know?

Other medicines, food and drink


Loss of fertility


Contraception and pregnancy




Treatment for other illnesses 





You can:

  • have the flu vaccine (as an injection)




More information about this treatment



Related links