Chemotherapy 101
Chemotherapy 101
Chemotherapy drugs
are to cancer cells what antibiotics are to bacteria. They interrupt the cell division process by preventing ongoing duplication of the cellular materials. As the immature cells die, new ones are not able to take their place and tumor growth is stopped. As chemotherapy is delivered in an ongoing fashion, more and more cancer cells are killed off, eventually, hopefully, getting them all.
Chemotherapy schedules
are usually spaced at intervals, to give the normal cells a chance to recover. Normal cells are also affected, but only a small fraction of them are in a vulnerable phase at any time. As the chemotherapy is eliminated from the body, the normal cell population recovers.
Chemotherapy delivery
has commonly been via an intravenous infusion. This is to ensure reliable delivery to the target. If they are taken in pill form, absorption has to be reliable. Then they have to pass through the liver without being inactivated, before being passed on to the general circulation. Such drugs have been developed and used, but the majority are still via an infusion.
Common Side effects:
On the blood cells:
occur when normal cells are depleted, causing depletion of normal blood cells. Decreases in the white cell count makes you vulnerable to infections, decreases in the red cell count causes anemia and fatigue. Decreases in the platelet cells can cause bruising or bleeding.
Nausea:
from the stimulation of the trigger zone in the brain, as well as an effect on the stomach lining.
Hair Loss:
from the effect on hair follicles. This is not a permanent effect, and the follicles will recover after completion of chemotherapy. Some drugs cause more hair loss than others.
Other side effects caused by some drugs, but not others: Heart
function effects, Numbness or tingling in the hands and feet (neuropathy), ringing in the ears, kidney function effects, and so on.
Most of these effects are anticipated, and often treated with preventive measures.