Imatinib is a type of chemotherapy medication that is mainly used to treat certain cancers of blood cells, including a type of leukemia called chronic myeloid leukemia. In addition, this medication can treat a skin tumor called dermatofibrosarcoma protuberans and a digestive system cancer called gastrointestinal stromal cancer. This medication is sold under the brand name Gleevec®.
This chemotherapy agent is a type of medication called a protein-tyrosine kinase inhibitor. Its mechanism of action is unique in that it is one of a very few types of cancer drugs that specifically target an enzyme that is highly active only in cancer cells. Imatinib targets a type of enzyme called a tyrosine kinase. In certain cancers, one specific type of tyrosine kinase enzyme is permanently active, whereas in healthy cells it usually is inactive. Imatinib prevents these cancer cells from multiplying by preventing the action of the tyrosine kinase, which reduces the rate at which the cancer is able to spread.
One of the biggest advantages of this medication is that because it specifically targets cancer cells, it has fewer serious systemic side effects than many other chemotherapy agents. Even so, there are some side effects associated with this drug. Possible side effects include constipation or diarrhea, nausea, vomiting, appetite loss, indigestion, muscle or joint pain, anxiety and depression. These side effects generally are mild and temporary, and anyone who experiences severe side effects, or side effects that persist, should consult his or her doctor.
Imatinib also has some potentially serious side effects. These include swelling of the feet, ankles, lower legs or hands; difficulty breathing; irregular or fast heartbeat; insomnia; coughing up bloody or pink mucus; chest pain; increased urination; fever; jaundice; blood in stool; skin that bruises easily; signs of infection; or fatigue. Anyone who experiences one or more of these symptoms, or any other unusual symptoms, should contact his or her doctor as soon as possible.
People who take this medication also must ensure that their doctors are familiar with any other medications they might be taking, because the list of drugs that can affect imatinib is extensive. There are possible drug interactions with painkillers, antibiotics, blood thinners, antifungals, calcium channel blockers, birth control pills, cholesterol-lowering medications, sleeping pills, tranquilizers and anti-seizure medications. In general, someone who takes this medication should ensure that his or her doctor knows about any and all medications he or she is using, including herbal preparations and supplements, as well as over-the-counter and prescription drugs.