Aprepitant is used with other medications to help prevent nausea and vomiting caused by cancer drug treatment (chemotherapy). Aprepitant 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 that has already started. Ask your doctor what you should do if you already have nausea or vomiting.

This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.

This medication may also be used for nausea and vomiting after surgery.

Read the Patient Information Leaflet if available from your pharmacist before you start taking aprepitant and each time you get a refill. If you are taking the liquid form of this medication, read the Instructions for Use sheet for directions on the proper use of this medication. If you have any questions, ask your doctor or pharmacist.

Take this medication by mouth with or without food as directed by your doctor. If you are taking capsules, swallow the capsules whole.

Take the first dose as directed by your doctor, usually 1 hour before the start of chemotherapy. For the next 2 days, continue to take a dose once daily 1 hour before the start of treatment if you are getting chemotherapy that day. If you are not getting any chemotherapy, then take the dose once daily in the morning.

The dosage is based on your medical condition, age, and response to treatment. Children's dosage is also based on weight. It is important to follow your doctor's instructions for when to take each dose, how long to keep taking it, and the strength (number of milligrams) of each dose. If you have any questions, ask your doctor or pharmacist.

Tell your doctor if you vomit or feel nauseated.

Tiredness or hiccups may occur. If either of these effects lasts or gets worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor 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 symptoms of a serious allergic reaction, including:

• 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 or at www.fda.gov/medwatch.

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 taking aprepitant, tell your doctor or pharmacist if you are allergic to it; or to fosaprepitant; 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 disease

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

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

It is unknown if this drug passes into breast milk. Consult your doctor before breastfeeding.

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.

Other medications can affect the removal of aprepitant from your body, which may affect how aprepitant works. Examples include azole antifungals (such as itraconazole, ketoconazole), diltiazem, macrolide antibiotics (such as clarithromycin, erythromycin), nefazodone, HIV protease inhibitors (such as nelfinavir), rifamycins (such as rifampin, rifabutin), ritonavir, St. John's wort, certain anti-seizure medicines (such as carbamazepine, phenytoin), among others.

Aprepitant can both speed up or slow down the removal of other medications from your body, which may affect how they work. Examples of affected drugs include elacestrant, flibanserin, lomitapide, pimozide, among others.

If you take warfarin, this drug may affect how well warfarin works in your body. Your doctor should test your blood during the 2 weeks after your aprepitant 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 reliable backup birth control methods while using this medication and for 1 month after the last dose. 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.

Aprepitant is very similar to fosaprepitant. Do not use fosaprepitant while using aprepitant.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

It is important to take each dose of this medication as scheduled. If you miss a dose, ask your doctor or pharmacist right away for a new dosing schedule. Do not double the dose to catch up.

Store the capsules at room temperature away from light and moisture. Do not store in the bathroom. Store the liquid in the refrigerator and discard any unused liquid after 72 hours. Do not freeze. When ready to use, the liquid form of this medication may be stored at room temperature for up to 3 hours. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.