All cytokines are proteins, which means they can be destroyed by stomach enzymes . So they cannot be taken orally. They have to be given by injections into a vein, into a muscle or under the skin. Antitumor antibodies—polyclonal or monoclonal—are also given by injection.
There can be side effects at the site of the injection such as redness or swelling. But since biological agents are getting into your system, the side effects can also be generalized, or systemic.
• Tumor vaccines have few or no side effects except muscle aches or, on occasion, low-grade fever.
• Most of the cytokines cause fever, fatigue and occasionally chills and a skin rash. They may cause changes in
blood pressure, usually decreasing it.
• Interferons and TNFs cause general malaise , sometimes called flu-like syndrome.
• IL-2 can give rise to extremely severe and life-threatening side effects. IL-2 causes the peculiar capillary leak
syndrome. If this develops, you may rapidly gain weight, experience a drop in your blood pressure and find it
difficult to breathe. Tissues become swollen as fluid accumulates and there are sometimes toxic effects on the
heart. Unless treatment is discontinued at this stage, IL-2 may cause kidney shutdown or respiratory arrest
and death.
For these reasons, high-dosage IL-2 is usually given in an intensive care unit, where blood pressure, urine
output and breathing can be closely monitored and side effects treated promptly to avoid failure of a vital organ.
