Symptom Management, Palliative Care, or Supportive Care to relieve side-effects is an important part of cancer care and treatment and should always form part of the overall treatment plan.

Cancer and Cancer Treatment can cause a variety of sleeping problems such as Hypersomnia, Somnolence Syndrome, Nightmares, and Insomnia. Other factors that can also cause these sleeping problems include emotional concerns or medical conditions unrelated to cancer.

We will discuss Hypersomnia, Somnolence Syndrome & Nightmares in this article and will deal with Insomnia on a separate Page.


Hypersomnia causes one to feel very sleepy during the day or want to sleep for longer than normal at night. Hypersomnia may also be called somnolence, excessive daytime sleepiness, or prolonged drowsiness.

Hypersomnia is similar to fatigue, but they are not the same. Fatigue is when one is feeling exhausted and has no energy, and the feeling is not relieved by sleep.

Excessive daytime sleeping and being unable to stay awake are not signs of fatigue, but could be signs of Hypersomnia.

Symptoms of hypersomnia can include:

  • Excessive amounts of deep sleep
  • Excessive sleepiness that isn’t reduced by taking a nap
  • Sleeping for 10 or more hours at a time
  • Trouble staying awake during the day

Hypersomnia can interfere with one’s relationships and prevent one from enjoying normal activities. It can also make dealing with normal day-to-day activities and family and school responsibilities a challenge for Children with cancer.

Hypersomnia can occur as a result of Cancer, Cancer Treatments, and other Medical Conditions, including:

  • Anaemia or a Low Red Blood Cell Count
  • Brain and Central Nervous System (CNS) Tumours
  • Cancer that has metastasised (spread) to the brain from somewhere else in the body
  • Certain types of Chemotherapy
  • Changes in Hormone Levels in the body
  • Other symptoms of cancer or side effects of cancer treatments, such as Hypercalcemia  (high levels of calcium); Hypokalemia (low levels of potassium); Hypothyroidism (insufficient thyroid hormones); and Depression
  • Some prescription and over-the-counter medications, such as Antidepressants, Anti-nausea Medications, Pain Medications, Sedatives, Antihistamines, and Sleeping Pills

Treating Hypersomnia must begin with finding and treating the cause, as that is the only way to relieve symptoms. Hypersomnia related to chemotherapy for instance, generally improves once treatment ends.

If your child’s Hypersomnia is being caused by other medications, their doctor may be able to adjust the dose or substitute a different medication. Your child’s doctor may also prescribe stimulant medications to help them stay awake during the day.

The following behavioural changes may help you manage your child’s Hypersomnia:

  • Let your child sleep a for few hours longer at night to avoid excessive sleepiness during the day;
  • Get your child to exercise daily in the morning or early afternoon, if possible;
  • Do some enjoyable activities with your child that require their full attention;
  • Try to get your child into a regular sleep schedule so that they go to sleep and wake up at the same time every day;
  • Make your child get out of bed and stay out of bed until bedtime;
  • Do not feed your child heavy meals and foods that make them sleepy during the day;
  • Do not give them any food or drinks that contain caffeine

Somnolence Syndrome

Somnolence Syndrome is a type of Hypersomnia in Children with Cancer that is specifically associated with Radiation Therapy to the head.

The symptoms of Somnolence Syndrome usually occur three to 12 weeks after Radiation Treatment ends, and can last from a few days to several weeks.

The symptoms of Somnolence Syndrome include:

  • Excessive drowsiness
  • Headaches
  • Irritability
  • Loss of Appetite
  • Low-grade Fever
  • Nausea and Vomiting
  • Sleeping up to 20 hours a day


Nightmares are vivid, frightening dreams which normally cause one to wake up and remember part or most of the dream. Most people have nightmares from time to time, but the frequency or vividness of nightmares can increase after a cancer diagnosis and during cancer treatment. Frequent nightmares can lead to a fear of going to sleep, restless sleep, and daytime sleepiness.

An increase in emotional stress is a common cause of nightmares. Because having cancer is frightening and stressful, especially for children, it is normal for them to experience some nightmares during treatment and recovery.

Nightmares may be a way in which the mind works through unresolved feelings and fears.

Other causes of nightmares may include:

  • Antibiotics
  • Heart Medications
  • Iron supplements
  • Pain medications
  • Pain that is not well-managed
  • Withdrawal from pain medications and some anti-anxiety medications

The following tips may help your child cope with nightmares:

  • Encourage your child to be honest about their fears and feelings and to discuss them with a family member or friend early in the day, rather than at night when they could actually frighten them again;
  • Encourage your child to find creative ways to express the content or themes of the nightmares such as drawing pictures depicting the nightmare or writing about them;
  • Play a game with your child in which you take turns to make up different endings or story-lines to the nightmares, and to then visualise these new endings or story-lines;
  • Remind your child that nightmares are not real, and they do not predict the future or cause bad things to happen;
  • If the nightmares increase or continue, cause your child excessive anxiety, or prevent them from getting enough peaceful sleep, it may be a good idea to make an appointment for them to speak to their doctor or a trained counselor.