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Generic Name: aprepitant (oral/injection) (a PREP i tant)
Brand Names: Emend

Medically reviewed by Jane Grigg, DipPharm. Last updated on Dec 3, 2019.

What is Emend?

Emend (aprepitant) blocks the actions of chemicals in the body that trigger nausea and vomiting.

Emend is used together with other medications to prevent nausea and vomiting that may be caused by chemotherapy.

Emend is given ahead of time and will not treat nausea or vomiting that you already have.

Emend capsules are for use in adults and children who are at least 12 years old. Emend oral suspension (liquid) can be given to adults and children as young as 6 months old.

Important Information

You should not use Emend if you also use pimozide. A serious drug interaction can occur when pimozide is used together with aprepitant.

If you have liver disease, you may need a dose adjustment or special tests.

Emend can make birth control pills less effective, resulting in pregnancy. This effect can last for up to 28 days after your last dose of this medication. Ask your doctor about using a non-hormone method of birth control (such as a condom, diaphragm, spermicide) to prevent pregnancy while taking aprepitant and for at least 1 month after your treatment ends.

There are many other drugs that can interact with Emend. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor. Keep a list of all your medicines and show it to any healthcare provider who treats you.

Before taking this medicine

You should not use Emend if you are allergic to aprepitant, or if you use another medicine called pimozide. Aprepitant can cause unwanted or dangerous side effects when used with pimozide.

To make sure this medicine is safe for you, tell your doctor if you have ever had:

Tell your doctor if you are pregnant or breastfeeding. You should not be treated with Emend injection if you are pregnant.

Emend can make hormonal birth control less effective, including birth control pills, injections, implants, skin patches, and vaginal rings. To prevent pregnancy while using Emend, use a barrier form of birth control: condom, diaphragm, cervical cap, or contraceptive sponge.

Keep using the barrier form of birth control for 1 month after your last dose of Emend.

How should I use Emend?

Take Emend exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets.

Emend oral is taken by mouth and the injection is given as an infusion into a vein. A healthcare provider will give you this injection.

Emend is not for long-term use. You will most likely need only 1 to 3 doses.

The first dose is usually given 30 to 60 minutes before treatment with chemotherapy. Follow your doctor's dosing instructions very carefully.

Emend oral can be taken with or without food.

Swallow the capsule whole and do not crush, chew, break, or open it.

Give the oral suspension (liquid) using only the dosing syringe provided.

If you also take warfarin (Coumadin, Jantoven), you may need extra "INR" or prothrombin time tests after you have used aprepitant.

Store Emend capsules at room temperature away from moisture and heat.

Store the prefilled liquid dosing syringe in the refrigerator, do not freeze. After taking the liquid out of the refrigerator, you must use it within 3 hours.

Throw away any liquid medicine not used within 3 days (72 hours) after you received it. Do not save it for later use.

Emend dosing information

Usual Adult Dose for Nausea/Vomiting - Chemotherapy Induced:

Day 1: 125 mg orally 1 hour prior to chemotherapy
Day 2 and 3: 80 mg orally in the morning
Duration of therapy: Three days
Fosaprepitant dimeglumine for Injection (115 mg) may be substituted for oral aprepitant (125 mg), 30 minutes prior to chemotherapy, on Day 1 only of the CINV regimen as an intravenous infusion administered over 15 minutes.

Day 1: 125 mg orally 1 hour prior to chemotherapy
Day 2 and 3: 80 mg orally in the morning
Duration of therapy: Three days
-Emend is administered in conjunction with a corticosteroid and a 5-HT3 antagonist.
-The recommended dosage of dexamethasone is 12 mg orally on day 1 administered 30 minutes prior to chemotherapy.
-The 5-HT3 antagonist is administered on day 1 only. Consult the package insert for the 5-HT3 antagonist dosing prior to initiation of treatment.

Usual Adult Dose for Nausea/Vomiting - Postoperative:

Recommended dose: a single, oral 40 mg dose administered within 3 hours prior to the induction of anesthesia

What happens if I miss a dose?

Call your doctor for instructions if you forget to use your medicine within the prescribed length of time before your chemotherapy.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using Emend?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Emend side effects

Get emergency medical help if you have signs of an allergic reaction to Emend: (hives, itching, difficult breathing, dizziness, trouble swallowing, fast heartbeat, wheezing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).

Call your doctor at once if you have:

  • a light-headed feeling, like you might pass out;

  • pain or burning when you urinate;

  • sores or white patches in your mouth or throat, sore throat;

  • low blood cell counts - fever, chills, tiredness, mouth sores, skin sores, easy bruising, unusual bleeding, pale skin, cold hands and feet, feeling light-headed or short of breath; or

  • dehydration symptoms - feeling very thirsty or hot, being unable to urinate, heavy sweating, or hot and dry skin.

Common Emend side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Emend?

Sometimes it is not safe to use certain medications at the same time. Some drugs can affect your blood levels of other drugs you use, which may increase side effects or make the medications less effective.

Many drugs can interact with aprepitant, and some drugs should not be used at the same time. Tell your doctor about all your current medicines and any medicine you start or stop using. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Emend only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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