Why do many chemotherapy drugs cause hair loss?

Unfortunately, scientists have yet to be able to locate specific features of malignant and immune cells that would make them uniquely targetable (barring some recent examples, such as the Philadelphia chromosome as targeted by imatinib). This means that other fast dividing cells such as those responsible for hair growth and for replacement of the intestinal epithelium (lining) are also affected.





In simpler terms, chemotherapy can't target the cancer cells themselves, only any cell in the body that grows quickly like hair, so it dies and falls out...Why do many chemotherapy drugs cause hair loss?
Hair is made up of cells, as is the finger %26amp; toe nails. Chemo drugs are designed to kill cells. Cancer cells but it does not know the difference between one cell then to the other. The hair cells are the first to go. The cells dead the hair falls out. The nails also turn dark %26amp; brittle. The hair begins to grow back quickly often between treatments. For some reason it is the old hair that goes. The hair that begins to grow back doesn't seem to be effected as much. I didn't lose all mine, but it was such a mess that I shaved it off myself. All back now %26amp; now it grows like mad.Why do many chemotherapy drugs cause hair loss?
Has something to do with the chemo killing the fast growing cells, apparently thats your hair, along with the cancer cells. Thats what the doctors told us when my daughter went through chemo. I guess the stronger the chemo the quicker it comes out. My daughter had intensive chemo and her hair nearly all fell out 2 weeks from first dose.
The idea behind chemotherapy is to kill off or stop the rapid division of cancer cells. The way this can work is because most body cells have already stopped growing. The heart cells have already created the heart so they no longer grow. The lung cells are done creating a lung so they stop growing. The liver cells have already created a liver so they no longer need to grow. Normal cells have some type of signal that stops them from growing once the organ or tissue has been created. Cancer occurs when something triggers one of the 'normal' cells in an organ or soft tissue or bone to start growing.





There are only a few other body cells that keep growing and one of them is the hair cells. The chemotherapy can not tell the difference between a cancer cell that is still growing and a hair cell that is growing. Thus, the chemotherapy stops the cancer and the hair from growing. The tumors hopefully die off, and the hair falls out.





Hair loss is temporary. Once the chemotherapy stops the hair grows back.





Something to keep in mind, hair grows in cycles so if the patient has chemotherapy and the hair is not in a growing cycle, the hair won't fall out. It took about three or four chemotherapy cycles before my sons hair fell out. His darker hair fell out first and he kept the lighter hair for about five months before losing it all.





CancerBackup UK: Hair Loss


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Radiation ?