Effectuez un dépistage du virus de l'hépatite B chez tous les patients cancéreux débutant un traitement systémique. Apprenez-en davantage sur le dépistage et la gestion du virus de l'hépatite B.

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Formulaire de médicaments

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lapatinib

( la-PA-ti-nib )

Other Name(s): Tykerb®

Apparence: oval tablet

lapatinib patient.pdf

lapatinib pour le patient.pdf

lapatinib

Pronunciation:

la-PA-ti-nib

Other Name(s):

Tykerb®

Appearance:

oval tablet

This handout gives general information about this cancer medication.

You will learn:

who to contact for help
what the medication is
how it is given
what to expect while on medication

This handout was created by Ontario Health (Cancer Care Ontario) together with patients and their caregivers who have also gone through cancer treatment. It is meant to help support you through your cancer treatment and answer some of your questions.

This information does not replace the advice of your health care team. Always talk to your health care team about your treatment.

Who do I contact if I have questions or need help?

My cancer health care provider is: _____________________________________________

During the day I should contact: _______________________________________________

Evenings, weekends and holidays: _____________________________________________

This page gives general information about this cancer medication.

You will learn:

who to contact for help
what the medication is
how it is given
what to expect while on this medication

This information was created by Ontario Health (Cancer Care Ontario) together with patients and their caregivers who have also gone through cancer treatment. It is meant to help support you through your cancer treatment and answer some of your questions.

This information does not replace the advice of your health care team. Always talk to your health care team about your treatment.

What is this treatment for?

For treating breast cancer.

What should I do before I start this treatment?

Tell your health care team if you have or had significant medical condition(s), especially if you have / had:

heart problems (including any family history, irregular heartbeat or fainting spells),
low salt levels in your blood (such as low potassium),
lung or liver problems,
recent diarrhea, or
any allergies.

Before starting lapatinib, make sure your health care team has given you instructions on how to manage diarrhea. This may include instructions on how to take medications such as loperamide. It is important to treat diarrhea as soon as it occurs.

Remember To:

Tell your health care team about all of the other medications you are taking.
Keep taking other medications that have been prescribed for you, unless you have been told not to by your health care team.

You will have a blood test to check for hepatitis B before starting treatment. See the Hepatitis B and Cancer Medications pamphlet for more information.

How is this treatment given?

This medication is taken once a day by mouth. Talk to your health care team about how and when to take your medication.
Swallow tablets whole with a large glass of water on an empty stomach, at least one hour before or at least one hour after a low-fat meal.
You may need more than 1 tablet to have the correct dose. Ensure you count the tablets correctly to get the right dose.
If a dose is missed, take your next scheduled dose on the following day. Do not double the dose to make up for the missed dose.
If you vomit (throw up) after taking your medication, talk to your health care team about what to do.

Warning: If you take too much of this medication by accident, or if you think a child or a pet may have swallowed your medication, you must call the Ontario Poison Control Center right away at: 1-800-268-9017.

Other medications you may be given with this treatment

To Treat Diarrhea

This medication can cause diarrhea. Diarrhea is when you have loose bowel movements (watery poo) or you need to go poo (have bowel movements) more often than usual.

You will be given a medication called loperamide (Imodium®) to help treat your diarrhea. Take this medication only if you need it.

Keep your loperamide with you all the time. When diarrhea starts, take the loperamide right away.

Talk to your health care team about how to take this medication.

DO this while on treatment

DO check with your health care team before getting any vaccinations, surgery, dental work or other medical procedures.

DO protect your skin from the sun. Wear a long sleeved shirt, long pants and a hat. Apply sunscreen with UVA and UVB protection and an SPF of at least 30. Your skin may be more sensitive to the sun and you could develop a bad sunburn or rash more easily.

DO NOT do this while on treatment

Stop Icon

DO NOT use tobacco products (such as smoking cigarettes or vaping) or drink alcohol while on treatment without talking to your health care team first. Smoking and drinking can make side effects worse and make your treatment not work as well.

DO NOT take any other medications, such as vitamins, over-the-counter (non-prescription) drugs, or natural health products without checking with your health care team.

DO NOT start any complementary or alternative therapies, such as acupuncture or homeopathic medications, without checking with your health care team.

DO NOT eat or drink grapefruit, starfruit, Seville oranges or their juices (or products that contain these) while on this treatment. These may increase the quantity of the medication in your blood and increase the side effects.

DO this while on treatment

Check Mark Icon

DO check with your health care team before getting any vaccinations, surgery, dental work or other medical procedures.

DO protect your skin from the sun. Wear a long sleeved shirt, long pants and a hat. Apply sunscreen with UVA and UVB protection and an SPF of at least 30. Your skin may be more sensitive to the sun and you could develop a bad sunburn or rash more easily.

DO NOT do this while on treatment

Stop Icon

DO NOT use tobacco products (such as smoking cigarettes or vaping) or drink alcohol while on treatment without talking to your health care team first. Smoking and drinking can make side effects worse and make your treatment not work as well.

DO NOT take any other medications, such as vitamins, over-the-counter (non-prescription) drugs, or natural health products without checking with your health care team.

DO NOT start any complementary or alternative therapies, such as acupuncture or homeopathic medications, without checking with your health care team.

DO NOT eat or drink grapefruit, starfruit, Seville oranges or their juices (or products that contain these) while on this treatment. These may increase the quantity of the medication in your blood and increase the side effects.

Will this treatment interact with other medications or natural health products?

Yes, this medication can interact with other medications, vitamins, foods and natural health products. Interactions can make this medication not work as well or cause severe side effects.

Tell your health care team about all of your:

prescription and over-the-counter (non-prescription) medications
other drugs and substances, such as cannabis/marijuana (medical or recreational)
natural health products such as vitamins, herbal teas, homeopathic medicines, and other supplements, or traditional medicines

Check with your health care team before starting or stopping any of them.

Talk to your health care team BEFORE taking or using these :

Anti-inflammatory medications such as ibuprofen (Advil^® or Motrin^®), naproxen (Aleve^®) or Aspirin^®.
Over-the-counter products such as dimenhydrinate (Gravol^®)
Natural health products such as St. John’s Wort
Traditional medicines
Supplements such as vitamin C
Grapefruit juice
Alcoholic drinks
Tobacco
All other drugs or substances, such as marijuana or cannabis (medical or recreational)

What to do if you feel unwell, have pain, a headache or a fever

Always check your temperature to see if you have a fever before taking any medications for fever or pain (such as acetaminophen (Tylenol^®) or ibuprofen (Advil^®)).
- Fever can be a sign of infection that may need treatment right away.
- If you take these medications before you check for fever, they may lower your temperature and you may not know you have an infection.

How to check for fever:

Keep a digital (electronic) thermometer at home and take your temperature if you feel hot or unwell (for example, chills, headache, mild pain).

You have a fever if your temperature taken in your mouth (oral temperature) is:
- 38.3°C (100.9°F) or higher at any time
OR
- 38.0°C (100.4°F) or higher for at least one hour.

If you do have a fever:

Try to contact your health care team. If you are not able to talk to them for advice, you MUST get emergency medical help right away.
Ask your health care team for the Fever pamphlet for more information.

If you do not have a fever but have mild symptoms such as headache or mild pain:

Ask your health care team about the right medication for you. Acetaminophen (Tylenol^®) is a safe choice for most people.

Talk to your health care team before you start taking ibuprofen (Advil^®, Motrin^®), naproxen (Aleve^®) or ASA (Aspirin^®), as they may increase your chance of bleeding or interact with your cancer treatment.

Talk to your health care team if you already take low dose aspirin for a medical condition (such as a heart problem). It may still be safe to take.

How will this treatment affect sex, pregnancy and breastfeeding?

Talk to your health care team about:

How this medication may affect your sexual health.
How this medication may affect your ability to have a baby, if this applies to you.

This medication may harm an unborn baby. Tell your health care team if you or your partner are pregnant, become pregnant during treatment, or are breastfeeding.

If there is any chance of pregnancy happening, you and your partner together must use 2 effective forms of birth control at the same time until at least 1 week after your last dose. Talk to your health care team about which birth control options are best for you.
Do not use hormonal birth control (such as birth control pills), unless your health care team told you that they are safe. Talk to your health care team about the safest birth control for you.
Do not breastfeed while on this medication and for at least 5 days after your last dose.

How to safely store and handle this medication

Keep lapatinib tablets in the original packaging at room temperature in a dry place, away from heat and light. Keep out of sight and reach of children and pets.
Do not throw out any unused lapatinib tablets at home. Bring them to your pharmacy to be thrown away safely.

How to safely touch oral anti-cancer medication

If you are a patient:

Wash your hands before and after touching your oral anti-cancer medication.
Swallow each pill whole. Do not crush or chew your pills.

If you are a caregiver:

Wear nitrile or latex gloves when touching tablets, capsules or liquids.
Wash your hands before putting on your gloves and after taking them off, even if your skin did not touch the oral anti-cancer medication.
Throw out your gloves after each use. Do not re-use gloves.
Do not touch oral anti-cancer medications if you are pregnant or breastfeeding.

What to do if anti-cancer medication gets on your skin or in your eyes

If medication gets on your skin:

Wash your skin with a lot of soap and water.
If your skin gets red or irritated, talk to your health care team.

If medication gets in your eyes:

Rinse your eyes with running water right away. Keep water flowing over your open eyes for at least 15 minutes.

What are the side effects of this treatment?

The following table lists side effects that you may have when getting lapatinib. The table is set up to list the most common side effects first and the least common last. It is unlikely that you will have all of the side effects listed and you may have some that are not listed.

Read over the side effect table so that you know what to look for and when to get help. Refer to this table if you experience any side effects while on lapatinib.

Very Common Side Effects (50 or more out of 100 people)
Diarrhea (May be severe) What to look for? Loose, watery, unformed stool (poo) that may happen days to weeks after you get your treatment. What to do? If you have diarrhea: Take anti-diarrhea medication if your health care team prescribed it or told you to take it. Do not eat foods or drinks with artificial sweetener (like chewing gum or ‘diet’ drinks), coffee and alcohol, until your diarrhea has stopped. Eat many small meals and snacks instead of 2 or 3 large meals. Drink at least 6 to 8 cups of liquids each day, unless your health care team has told you to drink more or less. Talk to your health care team if you can’t drink 6 to 8 cups of liquids each day when you have diarrhea. You may need to drink special liquids with salt and sugar, called Oral Rehydration Therapy. Talk to your health care team if your diarrhea does not improve after 24 hours of taking diarrhea medication or if you have diarrhea more than 7 times in one day. Ask your health care team for the Diarrhea pamphlet for more information.	Talk to your health care team if no improvement after 24 hours of taking diarrhea medication or if severe (more than 7 times in one day).

Very Common Side Effects (50 or more out of 100 people)

Side effects and what to do

When to contact health care team

Diarrhea

(May be severe)

What to look for?

Loose, watery, unformed stool (poo) that may happen days to weeks after you get your treatment.

What to do?

If you have diarrhea:

Take anti-diarrhea medication if your health care team prescribed it or told you to take it.
Do not eat foods or drinks with artificial sweetener (like chewing gum or ‘diet’ drinks), coffee and alcohol, until your diarrhea has stopped.
Eat many small meals and snacks instead of 2 or 3 large meals.
Drink at least 6 to 8 cups of liquids each day, unless your health care team has told you to drink more or less.
Talk to your health care team if you can’t drink 6 to 8 cups of liquids each day when you have diarrhea. You may need to drink special liquids with salt and sugar, called Oral Rehydration Therapy.
Talk to your health care team if your diarrhea does not improve after 24 hours of taking diarrhea medication or if you have diarrhea more than 7 times in one day.

Ask your health care team for the Diarrhea pamphlet for more information.

Talk to your health care team if no improvement after 24 hours of taking diarrhea medication or if severe (more than 7 times in one day).

Common Side Effects (25 to 49 out of 100 people)
Side effects and what to do	When to contact health care team
Rash; dry, itchy skin (May be severe) What to look for? You may have cracked, rough, flaking or peeling areas of the skin. Your skin may look red and feel warm, like a sunburn. Your skin may itch, burn, sting or feel very tender when touched. What to do? To prevent and treat dry skin: Use fragrance-free skin moisturizer. Protect your skin from the sun and the cold. Use sunscreen with UVA and UVB protection and a SPF of at least 30. Avoid perfumed products and lotions that contain alcohol. Drink 6 to 8 cups of non-alcoholic, non-caffeinated liquids each day, unless your health care team has told you to drink more or less. Rash may be severe in some rare cases and cause your skin to blister or peel. It may also cause "bulls-eye" markings on your skin. If this happens, get emergency medical help right away.	Talk to your health care team if it does not improve or if it is severe.
Nausea and vomiting (Generally mild) What to look for? Nausea is feeling like you need to throw up. You may also feel light-headed. You may feel nausea within hours to days after your treatment. What to do? To help prevent nausea: It is easier to prevent nausea than to treat it once it happens. If you were given anti-nausea medication(s), take them as prescribed, even if you do not feel like throwing up. Drink clear liquids and have small meals. Get fresh air and rest. Do not eat spicy, fried foods or foods with a strong smell. Limit caffeine (like coffee, tea) and avoid alcohol. If you have nausea or vomiting: Take your rescue (as-needed) anti-nausea medication(s) as prescribed. Ask your health care team for the Nausea & Vomiting pamphlet for more information. Talk to your health care team if: nausea lasts more than 48 hours vomiting lasts more than 24 hours or if it is severe	Talk to your healthcare team if nausea lasts more than 48 hours or vomiting lasts more than 24 hours or if it is severe.

Less Common Side Effects (10 to 24 out of 100 people)
Side effects and what to do	When to contact health care team
Fatigue (Generally mild) What to look for? Feeling of tiredness or low energy that lasts a long time and does not go away with rest or sleep. What to do? Be active. Aim to get 30 minutes of moderate exercise (you are able to talk comfortably while exercising) on most days. Check with your health care team before starting any new exercise. Pace yourself, do not rush. Put off less important activities. Rest when you need to. Ask family or friends to help you with things like housework, shopping, and child or pet care. Eat well and drink at least 6 to 8 glasses of water or other liquids every day (unless your health care team has told you to drink more or less). Avoid driving or using machinery if you are feeling tired. Ask your health care team for the Fatigue pamphlet for more information.	Talk to your health care team if it does not improve or if it is severe.
Mild Headache What to do? Take pain medication (such as acetaminophen) as needed. Read the above section: "What should I do if I feel unwell, have pain, a headache or a fever?" before taking acetaminophen (Tylenol®), ibuprofen (Advil®, Motrin®), naproxen (Aleve®) or Aspirin. These medications may hide an infection that needs treatment or they may increase your risk of bleeding. Ask your health care team for the Pain pamphlet for more information. If you have a sudden, severe headache get emergency medical help right away.	Talk to your health care team if it does not improve or if it is severe.
Hair thinning or loss What to look for? Your hair may begin to become thin or fall out during or after treatment. In most cases, your hair will grow back after treatment, but the texture or colour may change. In very rare cases, hair loss may be permanent. What to do? Use a gentle soft brush. Do not use hair sprays, bleaches, dyes and perms.	Talk to your health care team if this bothers you.
Low appetite What to look for? Loss of interest in food or not feeling hungry. Weight loss. What to do? Try to eat your favourite foods. Eat small meals throughout the day. You may need to take meal supplements to help keep your weight up. Talk to your health care team if you have no appetite. Ask your health care team for the Loss of Appetite pamphlet for more information.	Talk to your health care team if it does not improve or if it is severe.
Nail changes What to look for? You may have changes in nail colour, pain or tenderness, swelling of cuticles, or loosening of nails. Nails will slowly return to normal after treatment ends. What to do? Moisturize your nails and cuticles. Do not use nail polish and fake fingernails until your nails have gone back to normal. Wear gloves when doing house chores or gardening.	Talk to your health care team if it does not improve or if it is severe.

Other rare, but serious side effects are possible with this treatment.

If you have any of the following, talk to your cancer health care team or get emergency medical help right away:

Yellowish skin or eyes, unusually dark pee or pain on the right side of your belly
Irregular heartbeat, fainting spells or swelling in your legs, ankles and belly
Chest pain, shortness of breath, trouble breathing or coughing up blood
Signs of an allergy such as fever, itchiness, rash, swollen lips, face or tongue, chest and throat tightness
Unusual bleeding or bruising
Fever (oral temperature 38.3°C (100.9°F) or higher at any time, OR 38°C (100.4°F) or higher for at least one hour, chills, feeling hot or unwell

For more information on how to manage your symptoms ask your health care provider, or visit: https://www.cancercareontario.ca/symptoms.

Notes

July 2025 Updated/revised information sheet

The information set out in the medication information sheets, regimen information sheets, and symptom management information (for patients) contained in the Drug Formulary (the "Formulary") is intended to be used by health professionals and patients for informational purposes only. The information is not intended to cover all possible uses, directions, precautions, drug interactions or side effects of a certain drug, nor should it be used to indicate that use of a particular drug is safe, appropriate or effective for a given condition.

A patient should always consult a healthcare provider if he/she has any questions regarding the information set out in the Formulary. The information in the Formulary is not intended to act as or replace medical advice and should not be relied upon in any such regard. All uses of the Formulary are subject to clinical judgment and actual prescribing patterns may not follow the information provided in the Formulary.

Certaines de ces informations ou toutes, dans certains cas, n’apparaissent qu’en Anglais. Vous pouvez demander la version française

lapatinib

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Gestion des symptômes

Sécurité et administration des médicaments