Losing hair during chemo

I suppose I could try to find this out on the Internet (outside of straightdope.com) but my wife thought I should ask this of Cecil since I’ve become so fond of this website. So here goes: why is it that cancer patients lose their hair when undergoing chemotherapy?

Most chemotherapy drugs specifically attack rapidly dividing cells. These include not only cancer drugs, but also the cells in the hair roots. When these cells die, the hair falls out.

Follow-on question: Once chemotherapy is completed (successfully or otherwise), does the hair generally grow back, or not?

Does radiation therapy also cause hair to fall out? If so, for the same reason?

Yes, it grows back after a chemo treatment.

Just in the area affected by radiation (rather than all over the body, as in chemo), and for the same reason. Hair usually grows back, but not always if the dosage was too high.

It’s the same reason some chemo patients get open sores in their mouths. The rapidly dividing skin cells die, leaving open wounds. It’s called oral mucositis. It’s can also cause anemia by killing the rapidly dividing red blood cells.

Mine grew back curly. It straightened out a little as it got longer, and over a few years went back to being straight. I had long hair, and the radiation only went half up the back of my head, so the long straight hair on the top of my head covered the new curly hair.

One positive was that I didn’t have to shave under my arms for over a year, and even after that the hair under my arms was thin and sparse.

my hair never fell out but it got much thinner, only about half of what it was and it never got thick again. Also very slightly wavy now when it was perfectly straight.

Had throat cancer and due to radiation still (4 years later) dont have whiskers on my neck

I lost all the hair on my body except my eye lashes and eyebrows. The hair on my head grew back wavy at first then back to straight, no color change.

Body hair naturally has about a 5 month cycle of growth before it falls out anyway. You don’t normally notice because your hair is all in various stages of this cycle all the time. Well after chemo I guess a lot of my hair was on the same cycle because 6 month later I had huge bald swatches appear on my legs. My already lame facial hair was worse than normal including this really awful looking pencil-thin Clark Gable mustache thing.