However exposure to toxic chemicals such as Thallium and Arsenic may also produce a sudden loss of hair. Chemotherapy is used in the treatment of cancer to destroy the cancer cells which divide rapidly within the body. One side effect of this cancer treatment however is that it can also stop the growth of the hair and may cause the shedding of hair. Some hair follicles do not shed the hair but produce a narrower weaker hair which breaks off easily. Anagen effluvium caused by chemotherapy is only a temporary condition and in most cases hair growth will return to normal once treatment is finished.
Many people even claim that their hair grows back healthier and thicker than before.
Sometimes when the hair grows back the texture can be different. Some people who have had curly hair have claimed that their hair has grown back straight, and sometimes even the colour can become different. There is a wide range of drugs used in Chemotherapy and not all of these drugs cause hairloss. When hair loss occurs as a side effect of Chemotherapy it normally occurs very suddenly. Often the hair falls out in large clumps and in many cases it occurs overnight.