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URL of this page: https://medlineplus.gov/druginfo/meds/a604003.html

Aprepitant

pronounced as (ap re' pi tant)

Why is this medication prescribed?

Aprepitant is used with other medications in adults and children 6 months of age and older to prevent nausea and vomiting that may occur after receiving cancer chemotherapy treatment. It is also used with other medications in adults and children 6 months of age and older to prevent delayed nausea and vomiting that may occur several days after receiving certain chemotherapy medications. Aprepitant is not used to treat nausea and vomiting that you already have. Aprepitant is in a class of medications called antiemetics. It works by blocking the action of neurokinin, a natural substance in the brain that causes nausea and vomiting.

How should this medicine be used?

Aprepitant comes as a capsule and as an oral suspension (liquid) to take by mouth. To prevent nausea and vomiting caused by cancer chemotherapy, aprepitant is usually taken once daily, with or without food, during the first few days of your cancer chemotherapy treatment. You will probably take aprepitant 1 hour before your chemotherapy on days 1, 2, and 3 of your treatment. If you do not receive chemotherapy on days 2 and 3, then you will take aprepitant on those days in the morning. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take aprepitant exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

Aprepitant capsules come in two different strengths. Your doctor may prescribe both of the strengths for you to take at different times. You should be careful to take the right strength at the right time as directed by your doctor.

Swallow the capsules whole; do not split, chew, or crush them.

The oral suspension will be prepared by your healthcare provider and given to you in an oral dispenser. Store the oral dispenser in the refrigerator until it is time for your dose; however, it can be stored at room temperature for up to 3 hours before use. When ready to use, remove the cap from the dispenser before placing it in your mouth to slowly release the medication.

Aprepitant only works to prevent nausea and vomiting. Call your doctor if you already have these symptoms and do not begin to take aprepitant.

When used to prevent nausea and vomiting caused by cancer chemotherapy, aprepitant is usually used only during the first 3 days of the chemotherapy treatment cycles. Do not continue taking aprepitant longer than instructed by your doctor.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking aprepitant,

  • tell your doctor and pharmacist if you are allergic to aprepitant, any other medications, or any of the ingredients in aprepitant capsules or oral suspension. Ask your pharmacist for a list of the ingredients.
  • Some medications should not be taken with aprepitant. Other medications may cause dosing changes or extra monitoring when taken with aprepitant . Make sure you have discussed any medications you are currently taking or plan to take before starting aprepitant with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking aprepitant, please get the advice of your doctor or pharmacist..
  • You should know that aprepitant may decrease the effectiveness of hormonal contraceptives (birth control pills, patches, rings, and injections). You will need to use another method of contraception to prevent pregnancy while taking aprepitant. Talk to your doctor about other ways to prevent pregnancy while you are taking this medication..
  • tell your doctor if you have or have ever had liver disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you are taking or receiving hormonal contraceptives (birth control pills, patches, rings, implants, or injections) during treatment with aprepitant, you should also use an additional method of birth control (spermicide, condom) to avoid pregnancy during treatment with aprepitant and for one month after your final dose. Talk to your doctor about birth control methods while you are taking aprepitant and after treatment. If you become pregnant while taking aprepitant, call your doctor.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Aprepitant may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • weakness
  • tiredness
  • dizziness
  • diarrhea
  • constipation
  • gas
  • stomach pain
  • heartburn
  • nausea
  • hiccups
  • loss of appetite
  • headache
  • fever
  • hair loss

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:

  • hives
  • rash
  • itching
  • skin peeling or blisters
  • difficulty breathing or swallowing

Aprepitant may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store the capsules at room temperature and away from excess heat and moisture (not in the bathroom). The prepared oral suspension dose must be used within 72 hours of preparation; discard any unused doses after 72 hours.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (https://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include the following:

  • drowsiness
  • headache

What other information should I know?

Keep all appointments with your doctor.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Emend®
Last Revised - 10/15/2023