Hair loss can be a distressing side effect of chemotherapy and radiation treatment. Chemotherapy targets rapidly growing cancer cells. Cells in hair follicles also multiply rapidly. So the chemotherapy can affect these cells, as well. This may happen in the second or third week of treatment or later. How much hair you lose is affected by the drugs and doses used in chemotherapy.

Hair follicles are also sensitive to radiation therapy. Hair loss with radiation may be temporary or permanent. It all depends on the radiation doses and chemotherapy used. Scaling, redness and flaking of the scalp may happen during radiation. So use only gentle, unscented products on your scalp. Your doctor can prescribe a cream or lotion if redness and scaling persists.

There’s no way to prevent hair loss that may come with cancer treatment. The doctor’s decision on what treatments to use will be based on the cancer and what is best to treat it. Hair will likely re-grow in three to six months after therapy is completed. The color, texture and degree of curliness may be different with the re-growth.

While hair is lost, wear a cap or scarf, or consider a wig to cover and protect the scalp from sun, wind and weather. As hair re-grows, use a mild shampoo and avoid curling irons or hair-straightening techniques.

The best remedy for growing your hair back is to keep your scalp in good condition. Avoid irritating products on the scalp.

Keep in mind that when you see hair being lost, that means your cancer is being attacked!

Rebecca Campen, M.D., J.D., is an assistant professor of dermatology at Harvard Medical School. She divides her time between clinical practice of dermatology at the Massachusetts General Hospital and private practice in Savannah, Ga.