Aldesleukin is a manmade version of interleukin-2 (IL-2). It is a form of immunotherapy – it boosts the body's immune system to help fight cancer. IL-2 causes the body to make more of certain immune system cells, prompts immune system cells to be more effective, and causes the cells to make more of some other cytokines.

• If you are allergic to any medicines, dyes, additives, or foods.

• If you have a history of heart disease. In some people this drug may affect the heart's function or rhythm.

• If you have a history of lung disease (asthma, emphysema, chronic bronchitis, etc.) This drug may cause lung problems or make existing lung problems worse.

• If you have an autoimmune disease (rheumatoid arthritis, lupus, scleroderma, psoriasis, etc.). This drug stimulates the immune system, which may make these conditions worse.

• If you have any other medical conditions such as kidney disease, liver disease (including hepatitis), thyroid problems, bleeding or clotting problems, congestive heart failure, diabetes, gout, or infections. This drug may make some of these conditions worse. You may need closer monitoring of these conditions while being treated, or the drug dose, regimen, or timing may need to be changed.

• If you are pregnant, trying to get pregnant, or if there is any chance of pregnancy. It is not known if this drug might cause problems if either the male or female is taking it at the time of conception or during pregnancy. Men and women who are taking this drug should use some kind of birth control during treatment. It is important to check with your doctor about what kinds of birth control can be used with this medicine. This drug should be used during pregnancy only if the potential benefit is thought to justify the potential risk to the fetus.

• If you are breast-feeding. While no studies have been done, this drug may pass into breast milk and affect the baby. Talk with your doctor about the possible risks of breast-feeding while taking this drug.

• If you think you might want to have children in the future. It is not known if this drug can affect fertility. Talk with your doctor about the possible risk with this drug and the options that may preserve your ability to have children.

• About any other prescription or over-the-counter medicines you are taking, including vitamins and herbs.

The dose of IL-2 will depend on your weight, your general health, the type of cancer being treated, and how well you tolerate treatment.

It's common to experience low blood pressure during or soon after the infusion. A rare but more serious side effect is capillary leak syndrome, in which the small blood vessels in the body become leaky, allowing fluid to leave the bloodstream and enter other parts of the body. This results in low blood pressure, fluid buildup, and poor blood flow to the internal organs. Tell your doctor right away if you feel dizzy or notice sudden swelling or rapid weight gain, trouble breathing, abnormal heart beats, chest pain, or little or no urine output.

Many people taking this drug experience flu-like symptoms, which can include feeling tired all the time, as well as fevers, headache, and muscle and joint pains.

You may have nausea and vomiting on the day you receive this drug or in the first few days afterward. Your doctor may give you medicine before your treatment to help prevent nausea and vomiting. You may also get a prescription for an anti-nausea medicine that you can take at home. It is important to have these medicines on hand and to take them as prescribed by your doctor.

This drug may cause sores in the mouth or on the lips, which often occur within the first few weeks after starting treatment. This can cause mouth pain, bleeding, or even trouble eating. Your doctor or nurse can suggest ways to reduce this, such as changing the way you eat or how you brush your teeth. If needed, your doctor can prescribe medicine to help with the pain.

This drug may cause diarrhea. If left unchecked, this could lead to dehydration and chemical imbalances in the body. Your doctor will likely prescribe medicine to help prevent or control this side effect. It is very important that you take this medicine as prescribed. Make sure you get the medicine right away, so that you will have it at home when you need it.

This drug may cause drowsiness and may affect activities such as driving. Wait until you find out how it affects you before driving or operating other dangerous machinery. Alcohol, sedatives, "nerve pills," or sleeping pills may worsen this effect.

This drug can cause allergic reactions in some people when the drug is given. Mild reactions usually consist of fever and chills. More serious reactions happen rarely, but can be dangerous. Symptoms can include feeling lightheaded or dizzy (due to low blood pressure), fever or chills, hives, nausea, itching, headache, coughing, shortness of breath, or swelling of the face, tongue, or throat. Tell your doctor or nurse right away if you notice any of these symptoms during or after being given the drug. Your doctor or nurse will likely give you medicine to try to prevent an infusion reaction.

Your doctor will likely test your blood throughout your treatment, looking for possible effects of the drug on blood counts or on other body organs (described below). Based on the test results, you may be given medicines to help treat any effects. Your doctor may also need to reduce or delay your next dose of this drug, or even stop it altogether.

This drug may affect the function of your liver and kidneys. These organs normally help filter the blood and help the body get rid of certain chemicals. Therefore, the blood levels of any other drugs you are taking may be affected by this. Your doctor will likely check the function of these organs with blood tests on a regular basis. The drug may need to be stopped or the dose reduced if the changes are severe. If you have kidney disease or liver metastasis or other liver problems before starting treatment, the doctor may need to monitor you more carefully.

This drug may lower your blood platelet count in the weeks after it is given, which can increase your risk of bleeding. Speak with your doctor before taking any drugs or supplements that might affect your body's ability to stop bleeding, such as aspirin or aspirin-containing medicines, warfarin (Coumadin), or vitamin E. Tell your doctor right away if you have unusual bruising, or bleeding such as nosebleeds, bleeding gums when you brush your teeth, or black, tarry stools.

This drug can lower your white blood cell count, especially in the weeks after the drug is given. This can increase your chance of getting an infection. Be sure to let your doctor or nurse know right away if you have any signs of infection, such as fever, chills, pain when passing urine, new onset of cough, or bringing up sputum.

Do not get any immunizations (vaccinations), either during or after treatment with this drug, without your doctor's OK. This drug may affect your immune system, which could make vaccinations ineffective, or could even lead to serious infections. Try to avoid contact with people who have recently received a live virus vaccine, such as the oral polio vaccine or smallpox vaccine.

• flu-like syndrome (may include fever, chills, tiredness, headache, muscle and joint pain)*
• low blood pressure*
• nausea/vomiting*
• diarrhea*
• feeling weak
• confusion
• shortness of breath
• flushing of the face
• rash or dry, itchy skin
• low urine output
• abnormal blood tests which suggest that the drug is affecting the liver or kidneys (Your doctor will discuss the importance of this finding, if any.)

• feeling dizzy
• feeling drowsy*
• sores in the mouth or on the lips*
• loss of appetite
• abdominal pain
• increased heart rate or change in heart rhythm
• swelling in the face, hands, or feet
• trouble sleeping
• trouble concentrating
• runny nose
• lowered platelet count with increased risk of bleeding*
• lowered red blood cell count

• lowered white blood cell count with increased risk of infection*
• allergic reaction*
• cough
• coma

*See "Precautions" section for more detailed information.