Immunotherapy is any treatment regimen that involves using pharmaceuticals or other measures to either strengthen (activation immunotherapy) or weaken (suppression immunotherapy) the immune system. They use a wide class of pharmaceuticals known as immunomodulators and include cytokines, interleukins, chemokines and others. Activiation immunotherapy is used in the treatment of cancer and immune deficiencies. Suppression immunotherapy is used in transplants and allergies.