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Your child needs to take the medicine called lomustine (say: low-MUS-teen). This information sheet explains what lomustine does, how to give it, and what side effects or problems your child may have when he or she takes this medicine.

What is lomustine?

Lomustine is a medicine used to kill cancer cells.

You may hear lomustine called CCNU or by its brand name, CeeNU®. Lomustine comes in a capsule form.

Before giving lomustine to your child

Tell your doctor if your child has ever reacted badly to lomustine or to any other medication, food, colouring, or preservative.

Talk with your doctor or pharmacist if your child has any of the following conditions. This medicine may not be right for your child if he/she has:

  • infection or recent exposure to infection (e.g., chickenpox)
  • history of lung problems
  • any kidney problems

How should you give your child lomustine?

Follow these instructions when you give your child lomustine:

  • Give your child lomustine exactly as your doctor or your pharmacist tells you to, even if your child seems better.
  • Talk to your child's doctor before you stop giving this medicine for any reason. Your child may become ill if he or she stops taking this medicine suddenly.
  • Lomustine capsules should be swallowed whole. The capsules come in different sizes (10 mg, 40 mg, and 100 mg). Your child may need to take more than one capsule to get the right dose.
  • The best time for your child to take lomustine is at bedtime.
  • Lomustine should be taken on an empty stomach (one hour before eating or two hours after eating).
  • If your child cannot swallow the capsules, ask the pharmacist to suggest different ways to give the drug.
  • If your child vomits 30 to 45 minutes after taking lomustine, do NOT repeat the dose. If you are unsure as to whether or not to give another dose, call your doctor or contact nurse.

What should you do if your child misses a dose of lomustine?

  • Give the missed dose as soon as you remember.
  • If it is almost time for the next dose, skip the missed dose. Give the next dose at the regular time.
  • Do not give your child two doses to make up for one missed dose.

What are the possible side effects of lomustine?

Your child may have some of these side effects while he or she takes lomustine. Check with your child's doctor if your child continues to have any of these side effects, and they do not go away, or they bother your child:

  • nausea (upset stomach) and vomiting (throwing up): your child should receive medicine to prevent upset stomach and throwing up caused by lomustine
  • loss of appetite
  • diarrhea (watery bowel movements)
  • darkening of the skin
  • skin rash or itching

Call your child's doctor during office hours if your child has any of these side effects:

  • unusual tiredness or weakness
  • confusion, awkwardness
  • slurred speech
  • redness, pain, or sores on lips, tongue, mouth, or throat
  • urinating less often
  • yellow eyes or skin
  • white or clay-coloured stools
  • swelling of feet or lower legs
  • shortness of breath or dry cough

Most of the following side effects are not common, but they may be a sign of a serious problem. Call your child's doctor right away or take your child to Emergency if your child has any of these side effects:

  • fever or chills
  • cough or sore throat
  • blood in urine or stools
  • black tarry stools
  • unusual bruising or bleeding
  • lower back or side pain
  • trouble or pain while urinating
  • pinpoint red spots on the skin

What safety measures should you take when your child is using lomustine?

Keep all appointments at the clinic or doctor's office so that the doctor can check your child's response to lomustine.

Lomustine may cause sores in the mouth. Rinse your child's mouth with a mouthwash made from baking soda to help keep it clean. Your nurse or pharmacist can review this with you. Avoid store-bought mouthwash that contains alcohol, as it may sting and cause dry mouth.

Lomustine can lower the number of white blood cells in the blood temporarily, which increases your child's chances of getting an infection. Your child can take the following precautions to prevent infections, especially when the blood count is low:

  • Avoid people with infections, such as a cold or the flu.
  • Be careful when brushing or flossing your child's teeth. Your doctor, nurse, or dentist may suggest different ways to clean your child's mouth and teeth.
  • You and your child shouldn't touch your child's eyes or inside their nose without washing hands first.
  • Your child's nurse will review with you what to do in case of fever.

Lomustine can lower the number of platelets in the blood, which increases your child's risk of bleeding. You can take the following precautions:

  • Be careful not to cut your child when using a razor, fingernail scissors, or toenail clippers.
  • Your child should avoid contact sports where bruising or injury could occur.
  • Tell the doctor or dentist that your child is taking lomustine before your child has any operation, even on the teeth, or an emergency treatment.
  • Your child should not receive a permanent tattoo or any kind of body piercing.

Your child should not receive any immunizations (vaccines) without your child's doctor's approval. Your child or anyone else in your household should not get oral polio vaccine while your child is being treated for cancer. Tell your child's doctor if anyone in your household has recently received oral polio vaccine. Your child should avoid contact with anyone who has recently received this vaccine.

There is a chance that lomustine may cause birth defects if it is taken at the time of conception or if it is taken during pregnancy. If your child is sexually active, it is best that he or she use some kind of birth control while receiving lomustine.

Tell the doctor right away if your child may be pregnant.

After receiving lomustine, your child may not be able to have children or may have more difficulty having children. Your child's doctor will discuss this in more detail with you/your child.

After your child stops receiving lomustine, it may still cause side effects. These delayed effects may include certain types of cancer. Check with your doctor immediately if any of the following signs occur, even after lomustine treatment has stopped:

  • yellow eyes or skin
  • black tarry bowel movements
  • blood in urine or stools
  • lower back or side pain
  • stomach pain
  • cough or a hoarse voice
  • unusual bleeding or bruising
  • shortness of breath

Check with your child's doctor or pharmacist before giving your child any other medicines (prescription, non-prescription, herbal, or natural products).

What other important information should you know about lomustine?

Lomustine does not usually cause hair loss. If your child does lose his or her hair, it will grow back once your child is no longer receiving lomustine. Its colour and texture may change. Use a gentle shampoo and a soft brush.

Keep a list of all medications your child is on and show the list to the doctor or pharmacist.

Do not share your child's medicine with others. Do not give anyone else's medicine to your child.

Make sure you always have enough lomustine to last through weekends, holidays, and vacations. Call your pharmacy at least two days before your child runs out of medicine to order refills.

Keep lomustine at room temperature in a cool, dry place away from sunlight. Do NOT store it in the bathroom or kitchen.

Do not keep any medicines that are out of date. Check with your pharmacist about the best way to throw away outdated or leftover medicines.

Keep lomustine out of your child's sight and reach and locked up in a safe place. If your child takes too much of any medication, call the Ontario Poison Centre at one of these numbers. These calls are free.

  • Call 416-813-5900 if you live in Toronto.
  • Call 1-800-268-9017 if you live somewhere else in Ontario.
  • If you live outside of Ontario, call your local Poison Information Centre.

Disclaimer: The information in this Family Med-aid is accurate at the time of printing. It provides a summary of information about lomustine and does not contain all possible information about this medicine. Not all side effects are listed. If you have any questions or want more information about lomustine, speak to your health care provider.

Jennifer Drynan-Arsenault, BSc, RPh, ACPR