Why is this medication prescribed?
Aprepitant (Cinvanti) injection and fosaprepitant (Emend) injection are used along with other medications to prevent nausea and vomiting in adults that may occur within 24 hours after receiving cancer chemotherapy treatment. Aprepitant and fosaprepitant injections are also used along with other medications to prevent delayed nausea and vomiting that may occur several days after receiving certain chemotherapy medications. Aprepitant and fosaprepitant injections are not used to treat nausea and vomiting that you already have. Aprepitant and fosaprepitant injections are in a class of medications called antiemetics. Fosaprepitant is a medication that converts to aprepitant in the body shortly after it is given. Therefore both medications work in the same way in the body to block the action of neurokinin, a natural substance in the brain that causes nausea and vomiting.
How should this medicine be used?
Fosaprepitant injection (Emend) comes as a powder to be mixed with liquid and aprepitant injection (Cinvanti) comes as an emulsion (liquid) to be injected intravenously (into a vein) by a doctor or nurse in a medical facility. Fosaprepitant injection (Emend) is usually given by intravenous infusion over 20 to 30 minutes as a one-time dose, beginning about 30 minutes before the start of chemotherapy. Aprepitant injection (Cinvanti) is usually given by intravenous infusion over 30 minutes as a one-time dose, beginning about 30 minutes before the start of chemotherapy day 1 and then for some chemotherapy treatments, aprepitant oral (by mouth) is also given on chemotherapy days 2 and 3.
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 using aprepitant or fosaprepitant injection,
- tell your doctor and pharmacist if you are allergic to fosaprepitant, aprepitant, any other medications, or any of the ingredients in aprepitant (Cinvanti) injection such as egg lecithin and soybean oil) or fosaprepitant (Emend) injection such as polysorbate 80 and lactose anhydrous. Ask your pharmacist for a list of the ingredients.
- tell your doctor if you are taking pimozide (Orap). Your doctor will probably tell you not to use aprepitant or fosaprepitant injection if you are taking this medication.
- tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: anticoagulants ('blood thinners') such as warfarin (Coumadin, Jantoven); certain antifungals such as itraconazole (Onmel, Sporanox) and ketoconazole; benzodiazepines such as alprazolam (Xanax), midazolam, and triazolam (Halcion); certain cancer chemotherapy medications such as ifosfamide (Ifex), vinblastine, and vincristine (Marquibo); carbamazepine (Tegretol, Teril); clarithromycin (Biaxin, in Prevpac); diltiazem (Cardizem, Dilacor); certain HIV protease inhibitors such as nelfinavir (Viracept) and ritonavir (Norvir); hormonal contraceptives (birth control pills, patches, rings, and injections); nefazodone; oral steroids such as dexamethasone and methylprednisolone (Medrol); phenytoin (Dilantin, Phenytek); rifampin (Rifadin, Rimactane); and troleandomycin (TAO, no longer available in the U.S.). Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with aprepitant and fosaprepitant, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
- 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 birth control medications during treatment with aprepitant or fosaprepitant you should also use an additional method of birth control to avoid pregnancy during treatment with aprepitant or fosaprepitant and for 1 month after your final dose. Talk to your doctor about birth control methods while you are receiving aprepitant or fosaprepitant and after treatment. If you become pregnant while using aprepitant or fosaprepitant injection, call your doctor.
What special dietary instructions should I follow?
Unless your doctor tells you otherwise, continue your normal diet.
What side effects can this medication cause?
Aprepitant injection and fosaprepitant injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- tiredness or weakness
- pain, redness, or swelling at the injection site
Some side effects can be serious. If you experience any of these symptoms, stop using aprepitant or fosaprepitant and call your doctor immediately or get emergency medical treatment:
- shortness of breath
- difficulty breathing or swallowing
- peeling or blistering of the skin
- rapid or weak heartbeat
Aprepitant and fosaprepitant may cause other side effects. Call your doctor if you have any unusual problems while using 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 (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).
What other information should I know?
Keep all appointments with your doctor.
Do not let anyone else use 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.