Cancer loss of hair: Causes, symptoms and treatments

Death rates from cancer have declined significantly in recent years with treatment advancements playing a significant role. Although cancer treatments may help save lives, they may also cause distressing side effects, including hair loss.

Radiation can cause hair loss in some cases.  Whether radiation therapy leads to hair loss can depend on several factors, such as the type of radiation and the dose being given. If hair loss occurs, it is usually limited to the area being treated. For example, radiation therapy to the head can cause hair loss on the scalp.

Chemotherapy can cause hair loss in some cases. However, not all chemotherapy drugs cause hair loss. The amount of chemo hair loss can range from mild shedding to complete baldness. Hair loss can depend on several factors, such as the dose and type of chemotherapy drug being used. Some chemotherapy drugs can cause hair loss on all parts of the body, not just on the scalp.

Because the nature of the two cancer treatments is different, radiation and chemo hair loss may produce different symptoms:

Radiation hair loss

One to three weeks after the start of treatment, people undergoing radiation therapy may begin to notice hair loss. It typically progresses over time, and hair loss may not be obvious until one to two months following the start of therapy. You may find that the area where the hair loss occurred feels tender or sensitive.

The size of the area being treated and the intensity of the therapy often determine the amount of scalp hair a person loses. At low doses or in small areas, hair may simply thin. In other cases, a person may experience more significant hair loss that results in a bald spot or total baldness.

Chemo hair loss

For most people, chemo hair loss usually starts around two to four weeks following the start of treatment. Some people notice gradual loss, while others lose large chunks of hair. Scalp tenderness sometimes accompanies the loss. Normally, hair loss continues until a few weeks after treatment ends. With chemotherapy hair loss, total baldness may occur. You may also lose your eyelashes and eyebrows, in addition to pubic hair, underarm hair and hair on other areas of the body.

Following chemotherapy, hair usually grows back. Hair growth after chemo usually restarts two to three months after treatment. Hair loss from low-dose radiation therapy is also typically temporary, with regrowth occurring within three to six months. At higher doses, hair loss may be permanent, or hair may grow back thinner.

Many people find that hair growth after chemo or radiation may be different from the way it was prior to treatment. Hair may come in curlier or appear a different color. In some cases, these changes are temporary. As the growth process continues, hair may gradually return to normal. While the hair regrows, the affected area may feel itchy.

People facing chemotherapy or radiation treatment may hear of miracle products or home remedies that supposedly prevent hair loss. Unfortunately, there are no proven methods of stopping hair loss due to cancer treatment. Some studies suggest that wearing a cap filled with chilled liquid during chemotherapy may reduce hair loss. However, researchers cautioned that cooling the scalp might slightly increase the risk of scalp cancer, and there is not enough evidence to know for sure that cooling therapy is beneficial for everyone.

Healthcare providers sometimes advise patients to avoid chemical treatments like perms and color treatments prior to cancer treatment. They may also recommend using a gentle shampoo and conditioner and avoiding hair dryers, flat irons, curling irons and other thermal styling tools.  While following these steps will not prevent hair loss, they can help lessen the damage to your hair.

Some people find that cutting their hair short or shaving their head prior to the start of therapy makes the loss less traumatic. You may also wish to shop for a wig or head coverings before treatment so that you’re prepared if hair loss does occur. If you do experience hair loss, always apply sunscreen or wear a head covering whenever you go outdoors.

The most important thing that you can do after chemo or radiation is practice patience since hair growth takes time. Try to focus on the positive outcomes of treatment and celebrate the progress made. Adopt a gentle hair care routine, and use daily and leave-in conditioners to keep new growth hydrated.

You can also talk to your healthcare provider about whether minoxidil may be beneficial for you. Minoxidil is a topical treatment for hair loss that has been shown to stimulate growth. You usually apply it in liquid solution or foam form two to three times per day. Studies indicate that the over-the-counter medication may enhance hair growth after chemo and radiation in some people.

Any time that you experience hair loss or any other distressing or unpleasant side effects of radiation or chemotherapy, you should report them to your healthcare provider. They may share self-care practices or home remedies to alleviate the symptoms. They may also recommend over-the-counter or prescription treatment. 

Published October 2022.