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Drugs & Medications

fosaprepitant intravenous




Fosaprepitant is used with other medications to help prevent nausea and vomiting caused by cancer drug treatment (chemotherapy). Fosaprepitant works by blocking one of the body's natural substances (substance P/neurokinin 1) that causes vomiting.

This medication will not treat nausea or vomiting if you already have it. Contact your doctor for further instructions if you are experiencing nausea or vomiting.

How to use fosaprepitant intravenous

Read the Patient Information Leaflet available from your pharmacist before you start using this medication and each time you get a refill or receive treatment. If you have any questions, consult your doctor or pharmacist.

This medication is given by injection into a vein by a health care professional. Fosaprepitant is usually given as a single dose 30 minutes before your chemotherapy or as directed by your doctor. On the following 2 days, you will usually take the form of this medication given by mouth (aprepitant). If you have any questions, consult your doctor or pharmacist.

Rarely, a very serious allergic reaction to this drug might occur while your dose is being given (infusion reaction). Tell your health care professional right away if you experience any side effects such as flushing, redness, or trouble breathing during your treatment. The infusion may need to be stopped. If the infusion is stopped, tell your doctor about the infusion reaction and do not use fosaprepitant again.

Tell your doctor if you develop nausea or vomiting.

Side Effects

See also How To Use section.

Tiredness and hiccups may occur. If either of these effects persist or worsen, tell your doctor or pharmacist promptly.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any of the following symptoms of a serious allergic reaction: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.


Before using fosaprepitant, tell your doctor or pharmacist if you are allergic to it; or to aprepitant; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: liver problems.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is not known if this drug passes into breast milk. Consult your doctor before breast-feeding.


Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug include: cisapride, drugs affecting liver enzymes that remove fosaprepitant from your body (such as azole antifungals including itraconazole, macrolide antibiotics including erythromycin, cimetidine, rifamycins including rifabutin, St. John's wort, certain anti-seizure medicines including carbamazepine/phenytoin, certain cancer chemotherapy drugs including ifosfamide/vinblastine/vincristine), pimozide.

Fosaprepitant can both speed up and slow down the removal of other drugs from your body, thereby affecting how they work. These affected drugs include (not a complete list): benzodiazepines (e.g., alprazolam, midazolam, triazolam), simvastatin, drugs to treat erectile dysfunction-ED or pulmonary hypertension (e.g., sildenafil, tadalafil).

If you take warfarin, this drug may affect how well warfarin works in your body. Therefore, your doctor should test your blood during the 2 weeks after your fosaprepitant treatment to measure how well warfarin is working.

This medication may decrease the effectiveness of hormonal birth control such as pills, patch, or ring. This could cause pregnancy. Discuss with your doctor or pharmacist if you should use additional reliable birth control methods while using this medication and for 1 month after the last dose of this medication. Also tell your doctor if you have any new spotting or breakthrough bleeding, because these may be signs that your birth control is not working well.

Fosaprepitant is very similar to aprepitant. Do not take medications containing aprepitant while using fosaprepitant.


If overdose is suspected, contact a poison control center or emergency room right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.


Not applicable.

Missed Dose

It is important that you receive the dose before cancer chemotherapy as directed by your doctor. If you miss a dose, contact your doctor or pharmacist right away to establish a new dosing schedule.


Not applicable. This medication is given in a clinic and will not be stored at home.

Information last revised March 2014. Copyright(c) 2014 First Databank, Inc.


Sorry. No images are available for this medication.

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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

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