aprepitant / fosaprepitant

(Emend®, Emend IV®)

Other Names

Emend®, Emend® IV

Appearance

Aprepitant- Capsules (days 1 to 3) in various strengths

Fosaprepitant- Clear, colourless solution for injection (day 1 only)

aprepitant / fosaprepitant

Pronunciation:

ah-PREH-pih-tant / fos-ah-PREH-pih-tant

Other Name(s):

Emend®, Emend® IV

Appearance:

Aprepitant- Capsules (days 1 to 3) in various strengths

Fosaprepitant- Clear, colourless solution for injection (day 1 only)

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?

Used with other medications for preventing nausea and vomiting that may be caused by your chemotherapy treatment.

What should I do before I start this treatment?

• Tell your doctor and pharmacist if you have/had significant medical condition(s), especially if you have / had liver problems or any allergies.• You will receive other prescriptions for anti-nausea to be used before and/or after chemotherapy. Ensure you fill these prescriptions before you start your treatment. Follow your doctor and pharmacist's instructions carefully.

How is this treatment given?

• Take aprepitant as directed by your doctor. On day 1, the 125mg dose of aprepitant should be taken by mouth one hour before your chemotherapy treatment. The 80 mg dose should be taken by mouth each morning on days 2 and 3 of your chemotherapy cycle.• Aprepitant may be taken with or without food.• Swallow capsule whole with a glass of water.• Alternatively, your doctor may order fosaprepitant to be given by injection through your vein on day 1 only.• Aprepitant / fosaprepitant must be used with other anti-nausea drugs specified by your doctor. Make sure you understand and follow the instructions carefully, in order to receive the most benefit from these medications.

Other medications you may be given with this treatment

DO this while on treatment
Do not eat or drink grapefruit, starfruit, Seville oranges or their juices (or products that contain these) while on this treatment. They may increase side effects. This medication often interacts with other medications and can result in the treatment not working as well or cause severe side effects. Make sure your health care team knows about all your medications (prescription, over-the-counter, herbals and supplements). Check with your health care team before starting or stopping any of them.

DO this while on treatment

Check Mark Icon

Do not eat or drink grapefruit, starfruit, Seville oranges or their juices (or products that contain these) while on this treatment. They may increase side effects.

This medication often interacts with other medications and can result in the treatment not working as well or cause severe side effects.

Make sure your health care team knows about all your medications (prescription, over-the-counter, herbals and supplements). Check with your health care team before starting or stopping any of them.

DO this while on treatment

Check Mark Icon

Do not eat or drink grapefruit, starfruit, Seville oranges or their juices (or products that contain these) while on this treatment. They may increase side effects.

This medication often interacts with other medications and can result in the treatment not working as well or cause severe side effects.

Make sure your health care team knows about all your medications (prescription, over-the-counter, herbals and supplements). Check with your health care team before starting or stopping any of them.

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

Do not eat or drink grapefruit, starfruit, Seville oranges or their juices (or products that contain these) while on this treatment. They may increase side effects.

This medication often interacts with other medications and can result in the treatment not working as well or cause severe side effects.

Make sure your health care team knows about all your medications (prescription, over-the-counter, herbals and supplements). Check with your health care team before starting or stopping any of them.

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

Do not eat or drink grapefruit, starfruit, Seville oranges or their juices (or products that contain these) while on this treatment. They may increase side effects.

This medication often interacts with other medications and can result in the treatment not working as well or cause severe side effects.

Make sure your health care team knows about all your medications (prescription, over-the-counter, herbals and supplements). Check with your health care team before starting or stopping any of them.

How will this treatment affect sex, pregnancy and breastfeeding?

• Aprepitant is not recommended for use during pregnancy. Let your doctor know if you are pregnant or plan to become pregnant.• Aprepitant may reduce the effectiveness of birth control pills; therefore, alternative or back-up methods of birth control should be used during aprepitant treatment and for one month after the last dose of aprepitant. Discuss with your healthcare team.• Tell your doctor right away if you or your partner becomes pregnant.• Do not breastfeed while taking this drug.

How to safely store and handle this medication

Do not throw out any unused medications at home. Bring them to your pharmacy to be thrown away safely.

• Aprepitant: Store in the original packaging at room temperature, away from heat, light or moisture. Keep out of reach of children and pets.

What are the side effects of this treatment?

• The following side effects have been seen in people using aprepitant / fosaprepitant with other chemotherapy drugs, so some of these effects may also be related to chemotherapy.

• The following side effects are common or severe. You may not have all of the side effects listed, while others not on this list may also occur. Discuss with your doctor if you have any unusual or bothersome symptoms.

Very Common Side Effects (50 or more out of 100 people)
Side effects and what to do	When to contact health care team
*Poor Appetite; don't feel like eating; weight loss* Eat foods that you like and try to eat regular small meals. Use meal supplements if possible. See a dietitian.	Contact your health care team if no improvement or if severe
Constipation Eat a balanced diet with fibres such whole grains, fruit and raw vegetables. Drink plenty of fluids. Try light exercise regularly. Speak to your doctor if no bowel movement for 3 or more days. Also see Constipation Pamphlet.*	Contact your health care team if no improvement or if severe
Hiccups Drink clear fluids and avoid large meals.	Contact your health care team if no improvement or if severe
Diarrhea May occur days to weeks after the drug is given / after treatment starts. Drink plenty of clear fluids. Limit hot, spicy, fried foods, foods/drinks with caffeine, orange or prune juice. Try a low-fiber BRAT diet (Bananas, white Rice, Apple sauce, Toast made with white bread). Take anti-diarrhea drug(s) if given to you by your doctor. Also see Diarrhea pamphlet.*	Contact your health care team if no improvement or if severe
Tiredness Rest often; take naps if needed. Move slowly when getting up. Eat well-balanced meals and drink plenty of fluids. Light exercise may help. Do not drive a motor vehicle or operate machinery when feeling tired.	Contact your health care team if no improvement or if severe

Less Common Side Effects (10 to 24 out of 100 people)
Side effects and what to do	When to contact health care team
*Reactions at the injection site* (redness, itchiness, bruising, mild rash or swelling, with fosaprepitant use) • Let your health care team know right away when this happens, since this drug may irritate tissues if it leaks from the vein during injection.	-
Heart problems (irregular heartbeat, chest pain, fainting, swelling in legs/ankles/belly, shortness of breath)	Get emergency medical help right away
Blockage of an artery (blood vessel) in your heart, brain, chest, belly, or limbs; this may result in stroke (sudden loss of vision, speech, or the use of your limb(s)) or heart attack (chest pain, shortness of breath), or pain in chest, belly or limb	Get emergency medical help right away
Rupture in stomach or intestine wall (Sudden, severe pain in belly or stomach area)	Get emergency medical help right away
Allergic reaction (fever, severe rash, itchiness, swollen face, lip or tongue, chest or throat tightness; may occur during or shortly after the drug is given)	Get emergency medical help right away
Kidney problems (lower back pain, body swelling, passing little or no urine, or recent unusual weight gain)	Get emergency medical help right away
Lung problems (increased cough, breathing problems, chest pain, coughing blood)	Get emergency medical help right away
Rash; dry, itchy skin Stay out of the sun; wear sunblock, a hat and cover exposed skin. Use daily moisturizer. Severe rash may occur on the body/limbs with blistering or peeling of skin: Get emergency medical help right away if this occurs.	Contact your health care team if no improvement or if severe
Blood clot (limb pain or swelling, hardened vein in limb), may occur in lungs (sudden start of coughing, breathing problems, chest pain, coughing blood)	Get emergency medical help right away

Notes

August 2026 MIS eng-0819

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.

Last Updated: September 24, 2026

The information on this website is intended for informational purposes only and is not a substitute for medical advice. Always consult your health care provider if you have questions or concerns. The use of the information on this website does not create a physician-patient relationship between Ontario Health and you.
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