Hair loss, hair thinning and cancer drugs

About hair loss or hair thinning

Hair loss is one of the most well known side effects of cancer treatment. For many people losing their hair can be distressing and devastating.

It can be a constant reminder of your cancer and what you’re going through. But most people's hair will grow back once treatment has finished.

Cancer drugs can cause:

• mild thinning of your hair

• partial or patchy hair loss

• complete hair loss (alopecia)

Chemotherapy is the type of cancer drug treatment most likely to cause hair loss.

Complete hair loss is less likely with other types of treatment. But some other cancer drugs can cause hair thinning. It is not possible to tell beforehand who will be affected or how badly.

Hair loss also depends on factors such as:

• the type of drug or combination of drugs you are taking

• the dose

• the route (by mouth or as an injection or a drip through a vein)

• how sensitive you are to the drug

• your drug treatment in the past

Drugs that cause hair loss or thinning

Chemotherapy

Most people think that all chemotherapy drugs always cause hair loss. But only some chemotherapy drugs cause hair loss or slight hair thinning.

Chemotherapy drugs that cause hair loss can cause other hair to fall out too. This includes eyelashes, eyebrows, underarm, leg and sometimes pubic hair.

Hair loss is usually gradual rather than sudden. If your hair will fall out, it usually begins within 2 to 3 weeks after treatment starts.

Most people’s hair will grow back once chemotherapy treatment has finished. In very rare cases, the hair does not grow back. This only happens with very high doses of particular drugs. You can ask your doctor or specialist nurse whether your drugs are likely to cause hair loss.

Targeted cancer drugs

Hair loss from targeted drugs happens less than chemotherapy and varies depending on the type of targeted drug. Hair loss happens gradually. Changes to your hair can also happen during your course of treatment. These include changes such as:

• the texture of your hair

• how dense your hair grows

• the colour

• how quickly it grows back 

• eyelashes growing longer, thicker, and darker in colour

Hormone therapy

Hormone therapy usually causes hair thinning, rarely does it cause complete hair loss. Hair loss usually starts 3 to 6 months after starting treatment. It can continue until treatment ends years later.

Hair loss can depend on the type of hormone therapy you have.

Immunotherapy

Hair loss from immunotherapy varies depending on the drug. Hair loss may appear within a few weeks or after a year.

Find your cancer drug

When your hair grows back

Chemotherapy

Unless you have had very high doses of particular chemotherapy drugs, your hair will grow back once treatment is over.

There is evidence that in some people, after treatment with a type of chemotherapy called docetaxel, hair might take much longer to grow back. In a small number of people, hair loss might be permanent. This usually depends on the dose you’ve had and for how long you’ve had it. Speak to your doctor or specialist nurse if you are worried about this.

After chemotherapy, it may take several months for your hair to grow back. And your hair is likely to be softer. It might come back a different colour and be more curly. It will probably grow back at the same rate as before chemotherapy.

Your hair should return within 3 to 6 months after your treatment ends.

Other cancer therapies

Thinning hair caused by hormone therapy usually recovers, but it may take some time. You can usually see an improvement in your hair in about 3 to 6 months after stopping it. For full hair growth this could take longer than a year. In some people their hair doesn’t return to its usual fullness and it might remain thin.

Hair usually grows back once treatment with targeted drugs and immunotherapy has finished. With targeted drugs, it can happen even during treatment. With immunotherapy, it may vary.  

Your doctor or specialist nurse can tell you more about the risk of hair loss with your type of drug.

Coping with hair loss and hair thinning

There are tips you can follow that might help you if you are worried about hair loss or hair thinning from cancer treatment.

Find out more about the tips to cope with hair loss

Covering your head

There are a lot of ways to cover your head if your hair falls out. A wig is the most obvious choice, but some people prefer hats, scarves, beanies or caps. We have information about:

• the ways to cover your head

• what is available through the NHS

• where to get wigs and headwear

Ask your specialist nurse if you think you would like a wig.

Go to information about the different ways to cover your head

The following video is about 7 minutes 30 seconds long. Sheena lost her hair to chemotherapy and talks through the different types of headwear available.

Go to information about where to get wigs, hat and scarves

Reducing hair loss from chemotherapy

Your doctor will want to give you the treatment that's most likely to work best in treating your cancer. But sometimes there is a choice of drugs you can have.

Speak to your doctor if you find the thought of losing your hair very upsetting. Your doctor might be able to suggest a treatment that is less likely to cause hair loss. It's worth discussing.

Cold caps (scalp cooling)

Your doctor might suggest you try a cold cap. This is also called scalp cooling. This can sometimes reduce the amount of hair loss.

You wear a cold cap to lower the temperature of your scalp. This reduces the blood flow in the scalp. And this lowers the amount of drug reaching the hair follicles on your head. With less of the cancer drugs getting to the hair follicles, the hair is less likely to die off and fall out.

Problems with cold caps

Scalp cooling only blocks certain chemotherapy drugs and doesn't work for everyone. So you might still have hair thinning or lose your hair completely. You can't tell whether it will work for you until you try it.

Doctors can’t use scalp cooling for all types of cancer. You can't have scalp cooling if there is a risk of high levels of circulating cancer cells in your scalp blood vessels. This is because the cells in these blood vessels might survive the treatment.

So, scalp cooling isn't usually suitable for people:

• with cancers such as leukaemia and lymphoma

• who are due to have or have had radiotherapy to their scalp

Scalp cooling is also not suitable for people with the following conditions:

• cryoglobulinemia

• posttraumatic cold dystrophy

• cold agglutinin disease

• cold sensitivity

• cryofibrinogenemia

• cold migraine

• cold urticaria

You can't have scalp cooling when undergoing continuous chemotherapy through a pump or chemotherapy tablets. This is because you would need to wear a cold cap 24 hours a day.

Some people worry their cancer might spread to the scalp (metastasise) if they’ve used a cold cap during chemotherapy. Researchers did a ​systematic review​ of studies in 2018. The review showed a very small risk of cancer spreading to the scalp after using a cold cap.

How you have scalp cooling

You have to spend longer at the hospital having your treatment if you have scalp cooling. You need to wear the cold cap for 30 minutes before you have your drugs. So bring something to distract you, such as a book to read or a film to watch.

It might make you feel cold all over. Wear a jumper or ask for a blanket. Hot drinks will help you feel warmer. Some people find that the cold cap gives them a headache. You can take paracetamol if you find it painful.

You have to continue wearing the cold cap for some time afterwards. This can be between 20 to 90 minutes. The time you need to wear it will depend on what type of chemotherapy drug you’ve had.

Ask your specialist nurse if wearing a cold cap during chemotherapy is suitable for you. If you're worried, you can discuss the possible risks with your specialist nurse.

Find out more about scalp cooling

Patient stories on hair loss and thinning

People react differently to cancer drugs. Here are some stories from cancer patients: