Difficulty sleeping (insomnia)

Many people affected by cancer can have difficulty sleeping. This is called insomnia. Long periods of not sleeping well can lead to other problems.

There are some things you can do to try to improve your sleep. These include:

  • having a regular bedtime routine
  • being more physically active during the day
  • making sure your bedroom is not too hot, too cold, too light or too noisy
  • having a snack before bed
  • avoiding drinks that contain caffeine, sugar and alcohol, such as tea, coffee and cola
  • not using a mobile phone, tablet or computer or watching the TV just before bed.

If worry and anxiety are keeping you awake, talking to someone may help. Writing down your worries a few hours before bedtime can help clear your mind. Breathing and relaxation exercises may also be useful to reduce anxiety and stress.

Some medicines used in the treatment of cancer can affect your sleep. Your doctor or nurse can give you advice on coping with this.

You may be able to take sleeping tablets to help. These can have side effects, so they are usually prescribed for only 1 to 2 weeks. There are also some behavioural therapies that can help. Your GP can tell you if these are suitable for you.

What is insomnia?

Insomnia means having difficulty getting to sleep, staying asleep, or waking up feeling unrefreshed or tired (fatigued). Many people affected by cancer have trouble sleeping, for lots of different reasons.

Insomnia includes having some or all of the following symptoms:

  • Difficulty getting to and staying asleep, or waking too early.
  • Difficulty sleeping despite good conditions for sleep, such as having a comfortable bed in a quiet, darkened room.
  • Daytime activities being affected by lack of sleep. For example, problems concentrating at work, falling asleep during the day or starting to have a low mood.

Other types of sleep problems

If you only sleep for a few hours every night, you may be worried that you have insomnia. But you may need less sleep if you are doing less. If you do not feel sleepy during the day, you may not need to worry about not sleeping much at night.

Some people have less sleep at night but catch up with a short afternoon nap, which can be refreshing. Other people, such as night shift workers or parents with small children, might be sleep deprived but not have insomnia. This generally means that they would be able to sleep quite well given the right conditions.

It is normal to wake briefly at the end of each sleep cycle. A sleep cycle lasts about 90 minutes. As we get older, we sleep less deeply and wake up more during the night. But if you wake up a lot, take a long time to get back to sleep and wake in the morning tired, you may need help to improve your sleep quality.

Losing one night of sleep will not have any effect other than leaving you feeling tired the next day. But long periods of sleeplessness can lead to anxiety, depression, concentration problems and difficulty making decisions. If you are worried that disturbed sleep is affecting how you function during the day, talk to your doctor or specialist nurse.

Causes of insomnia

Many different factors can influence sleep and cause insomnia. Some are everyday things that anyone can experience, such as life stresses. Others are more common in people affected by cancer.

Here are some things to think about that may be affecting your sleep:

  • Is your bedroom too hot, too cold, too light or too noisy?
  • Is your bed uncomfortable?
  • Do you have a poor sleep routine (see below)?
  • Do you have a partner who has a different sleep routine from your own?
  • Do you smoke, or drink alcohol or caffeine?
  • Are you currently not doing any physical activity during the day?
  • Do you take medicines that disrupt sleep, such as steroids?
  • Are you anxious, worried or suffering from emotional distress?
  • Do you have any physical problems such as pain, discomfort or feeling unwell?
  • Are you sleeping too much during the day?

Things you can do to improve sleep

Having good sleep habits can help improve sleep. This includes having a regular bedtime routine (sometimes called good sleep hygiene).

Routines, such as having a hot drink (but not tea or coffee), brushing your teeth or reading in bed for a while, can let your brain know that it is time to sleep. We have included some suggestions below of other things that could help you sleep better.

Sleep for the right amount of time

Spending too much time in bed is likely to affect the quality of your sleep. Try to sleep for just long enough to feel refreshed the next day, without oversleeping. Most adults need between 7 and 8 hours of sleep. But this can vary, so work out what is best for you.

Try to increase your physical activity

This could help you sleep better in the long term. It may be difficult if you have recently had treatment and are struggling to cope with energy levels or side effects. But increasing the amount of physical activity you do during the day can help to build up your strength and improve the quality of your sleep. Even something small will help, such as regular short walks or gentle gardening. But be aware that some people find exercise just before bedtime can disturb sleep.

We have more information about the benefits of physical activity before and after cancer treatment.

Go to bed and wake up at the same time each day

This is not always possible, but it can help you get into a good sleep routine.

Keep your bedroom for sleeping

If you wake during the night and find it difficult to go back to sleep, go to another room in your home. If you need to sleep during the day, go to your bedroom and sleep.

Make your bedroom a relaxing place

Create an area that is dark, quiet and comfortable. Having too much light in the bedroom can make it hard to fall asleep. It can affect the body’s internal sleep clock (also called the circadian rhythm). The sleep clock roughly follows a 24-hour cycle. To help us sleep during the night and be awake during the day, the sleep clock has to be regulated with reduced light at night and light exposure during the day. Dark curtains or a blind can help to reduce the amount of light in the bedroom.

Noise can also keep you awake. Even occasional loud noises can affect sleep, such as an aircraft flying over your home. If your bedroom is noisy, using ear plugs may help.

Keep a constant temperature in your bedroom

If your room is either very warm or very cold, your sleep may be affected. The room temperature should be comfortably warm.

Avoid watching TV or using a computer before bed

It can help to avoid watching the TV or using a mobile phone, tablet or computer shortly before going to bed. The screens on these devices emit a blue light that can make it harder to fall and stay asleep. The content may also stimulate mental activity, which can delay sleep.

Have a bedtime snack, but avoid stimulants

Hunger can disturb sleep. Try having a light bedtime snack, warm milk or a hot drink before going to bed. But avoid large meals, a lot of fluids and food and drinks that contain stimulants, such as caffeine or lots of sugar. Try to avoid:

  • coffee
  • tea
  • cola
  • chocolate, especially dark chocolate and chocolate drinks.

It is a good idea to avoid smoking cigarettes in the late evening too.

Limit how much alcohol you drink before bedtime

While alcohol can help people to fall asleep more quickly, their sleep tends to be interrupted. It may also wake you with a dry mouth and an unpleasant taste. It is best to limit how much alcohol you have near bedtime. Even a small amount of alcohol can make insomnia worse for some people.

Understand how naps affect you

Some people find that short daytime naps can help them sleep better at night, while others sleep less well after them. A short nap after lunch is likely to be better than one during the evening. Find out what suits you best.

Try mental exercises

These could also help you sleep, as they focus your brain away from worries. Here are a few mental exercises that you might like to try, which usually take about 10 minutes:

  • Try to remember the lines of a song or poem.
  • Make alphabetical lists, for example of names or countries.
  • Try to remember a favourite experience in detail.

Get out of bed if you are unable to sleep

Rather than lying in bed, take a brief break from trying to sleep. Get out of bed and try to empty your mind of thoughts or frustrations about not being able to sleep. Go back to bed after 10 minutes. You can repeat this if you are still unable to settle. It is probably best to avoid watching TV or using computers, phones or anything with a bright light when you are up.

However, some people find listening to a familiar story or watching a non-stimulating programme on TV can lull them to sleep. You could set a timer to switch off the device after a short period of time.

I limit my screen time before bed and try not to eat anything after 7pm. Try wearing comfortable bed clothes. Sometimes reading a book really helps me to nod off.

Chridster (Online Community member)

Worry and anxiety as a cause of insomnia

Being diagnosed with cancer can naturally cause feelings of worry and anxiety. These can stop you being able to sleep. Many people find they stay awake, going over the same thing in their mind. It may help to try some of the tips below.

Write down your concerns

If you wake at night and are worrying about things, write them down. There might be nothing you can do about them straight away. But if you write them down, you can then work through them during the day. You could ask for support from a family member or friend, or from your doctor or specialist nurse.

Talk to someone

Many people find that their fears and worries are reduced simply by telling someone else about them. Doing this can often be a real relief, and you may find that you sleep better afterwards.

Try talking to a close friend or family member. Or you might prefer to talk to someone outside your family. Some people find it helpful to share their worries with an online community, such as Macmillan’s Online Community. Or you may want to talk to a counsellor. Your GP may be able to refer you to a local counsellor, or you could contact Samaritans by calling their 24-hour confidential helpline on 116 123.

Try relaxation techniques

Simple breathing and relaxation exercises may be very useful in reducing anxiety and stress. They can also reduce muscle tension. Many people with cancer and their relatives find that these simple methods relax them.

Almost anyone can learn relaxation techniques. You can learn them at home using CDs or podcasts, or you may prefer to join a group. Self-help exercises need motivation and regular practice to provide ongoing benefit. It may be easier to stay motivated by going to group classes.

Lying flat can be uncomfortable for people who are breathless or in pain. But many relaxation exercises can be done sitting up or using pillows for support. We have a free CD which can help you learn the ways to manage breathlessness.

The following organisations also have relaxation tapes and CDs, which are available to buy:

Some hospitals and support groups offer relaxation sessions. You can ask if they are provided at your hospital.

Medicines that can cause insomnia

Many medicines for cancer and some other illnesses can upset sleeping. Drugs used to treat cancer that can cause sleeplessness include:

Not everyone who takes these drugs will have problems sleeping, as medicines affect people in different ways. You can discuss the possibility of your medicines affecting your sleep with your doctor or specialist nurse. They may be able to give you advice. For example, it can help to take medicines that make you very alert, such as steroids, in the morning.

Some other medications do not cause sleeplessness directly, but prevent you from sleeping due to other side effects. Many of the hormonal therapies for breast and prostate cancer can cause hot flushes and sweats, which can keep you awake at night. Your doctor or specialist nurse may be able to offer some help and advice with these side effects so that you are able to sleep.

Some of your medicines may cause drowsiness. It may be more helpful to take these at bedtime. But it is important to check with a member of your healthcare team before making any changes to your medicine timings.

Treating insomnia with sleeping tablets

If sleep becomes very difficult and is affecting your daily life, it can sometimes help to take a short course of sleeping tablets. Doctors normally want this to be a short-term solution, as sleeping tablets can have side effects.

Generally, sleeping tablets are only prescribed for 1 to 2 weeks. If you think this may help, talk about it with your doctor. They can advise whether tablets are suitable in your situation.

There are different types of sleeping tablet that work in different ways:


These work by increasing the effect of a substance in the brain called gamma-aminobutyric acid (GABA). GABA is a chemical messenger that gives a feeling of calm and drowsiness. Some benzodiazepines are short-acting and can help you get to sleep. Others are long-acting and can help you stay asleep.

Examples of benzodiazepines include:

  • temazepam
  • diazepam
  • lorazepam.


These work in a different way from benzodiazepines and have a different chemical structure. But they also help you to sleep by increasing GABA in the brain. They are sometimes called Z-drugs.

Examples include:

  • zolpidem (Stilnoct®)
  • zopiclone (Zimovane®).

Side effects of sleeping tablets

Most people experience the side effects of sleeping tablets the following day, once they wake up. These are often described as being like the after effects of drinking too much alcohol (a hangover). They usually go away quite quickly.

Some of the most common side effects of sleeping tablets are:

  • clumsiness or poor co-ordination
  • feeling light-headed, dizzy or still sleepy
  • difficulty concentrating and thinking clearly, or feeling ‘foggy’.

Sleeping tablets may increase the risk of a fall if you have to get up during the night, for example if you have to go to the toilet.

You should not drive if you feel sleepy, dizzy or unable to concentrate.

Tolerance and dependence on sleeping tablets

Doctors may sometimes seem cautious when prescribing sleeping tablets. This is because sleeping tablets can cause problems with tolerance and dependence. It is helpful to understand the difference between these two terms.

Tolerance to a drug means that as you continue to take it, it begins to feel as though it is no longer helping. It can also mean that you need a higher dose to get the same effect. In time, the higher dose will also begin to feel as though it has no effect, while side effects may worsen.

Dependence on a drug means that you may get withdrawal symptoms if the tablets are suddenly stopped. Withdrawal symptoms can include:

  • feeling anxious
  • feeling restless
  • difficulty sleeping.

For some people, this can feel similar to the symptoms of insomnia, for which the tablets were prescribed.

Tolerance and dependence may sound worrying, but most people do not have these problems if they are only taking sleeping tablets for a short period. Talk to your doctor if you are worried about tolerance or dependence. Your doctor will also check how you are getting on while you are taking sleeping tablets, to prevent this from happening.


Melatonin (Circadin®) is a naturally occurring hormone that is available as a tablet. It is used to treat insomnia as well as some other conditions. In the UK, melatonin is only licensed to be given as a short-term treatment for insomnia to people over the age of 55. So far, research has shown that melatonin causes fewer problems with tolerance and dependence. But for most people, it only reduces the time it takes to get to sleep by about 30 minutes.

Over-the-counter medicines

Sleeping tablets do not always need to be prescribed by a doctor. Over-the-counter (OTC) sleeping tablets can be useful in the short term. But many people find they develop a tolerance to these drugs if they take them for long periods.

OTC sleeping tablets often contain anti-allergy medication (antihistamine) and are not suitable for everyone. They may also not be recommended if you are taking some other types of medicine. If you are thinking of trying an OTC medicine, speak to your doctor, specialist nurse or pharmacist first.

Treating insomnia with behavioural therapies

Behavioural therapies help to change the way you think, feel and behave when it comes to sleeping, bedtime or worrying at night. There are three main types of behavioural therapy that can be used for improving sleep:

Sleep restriction

For some people, spending too much time in bed means they wake up too early. Sleep restriction aims to help you go to bed at certain times, usually later than you normally would. This helps you get regular amounts of good-quality sleep.

Stimulus control

People who regularly have difficulty sleeping can have a strong mental link between their bed and not sleeping. This therapy aims to break that link by only using the bed for sleeping. Other activities such as watching television, using a laptop, organising things or eating should be done elsewhere in the house.

If lying in bed worrying is the problem, this therapy recommends you go to another room and try to distract yourself until you feel tired. This aims to break the mental link between your bed and worrying.

Mindfulness can help some people who have trouble getting to sleep because their mind becomes active at bedtime with a range of thoughts. Mindfulness is a way of focusing your thinking on the present moment and accepting how you are feeling. There are various mindfulness techniques available, including a range of apps for your phone or tablet.

Cognitive behavioural therapy for insomnia (CBT-I)

Cognitive behavioural therapy (CBT) is done by a trained therapist. This type of therapy aims to change negative ways of thinking that may increase worries and anxiety. Reduced anxiety may help you get more sleep.

Some of these therapies can be done by a GP with specialist training, or you may be referred to a clinical psychologist.

Cognitive Behavioural Therapy for Insomnia (CBT-I) is a programme which combines:

  • sleep hygiene (having a regular bedtime routine)
  • sleep restriction (see above)
  • stimulus control (see above)
  • relaxation techniques.

It also addresses negative thoughts about sleep. It can help you deal with worries about not having enough sleep and the effect this can have on your day-to-day routine.

CBT-I is available through some psychology services, either on an individual basis or in groups.

If you think some of these therapies could help you, speak to your GP.

Back to Other side effects

Avoiding infection

Cancer and its treatments can weaken the immune system. It’s important to try and avoid infection if your immunity is reduced.

Nausea and vomiting

Cancer and its treatment can make you feel sick (nauseous) or be sick (vomit). There are drugs that can help control this.