Fosaprepitant — Discount Pricing

Other medications in Oncology Support

• Ondansetron ODT
• Palonosetron
• Aprepitant
• Darbepoetin Alfa

About Fosaprepitant

Fosaprepitant is a crucial medication often used to prevent chemotherapy-induced nausea and vomiting (CINV), a common and distressing side effect of cancer treatment. Understanding how it works and its typical costs can help you navigate your care. With TheDrugClub, members can access significant savings on essential prescriptions like fosaprepitant, helping to make vital treatments more affordable.

What is Fosaprepitant and What Does it Treat?

Fosaprepitant is an antiemetic medication, meaning it's designed to prevent nausea and vomiting. Specifically, it's primarily used to combat chemotherapy-induced nausea and vomiting (CINV), one of the most feared side effects of cancer treatment. CINV can significantly impact a patient's quality of life, leading to poor nutrition, dehydration, and a reluctance to continue treatment. Fosaprepitant is often prescribed as part of a multi-drug regimen to prevent both acute (within 24 hours of chemotherapy) and delayed (more than 24 hours after chemotherapy) phases of CINV.

How Does Fosaprepitant Work?

Fosaprepitant belongs to a class of drugs called neurokinin-1 (NK1) receptor antagonists. It works by blocking the action of Substance P, a natural chemical in the body that plays a key role in transmitting nausea and vomiting signals to the brain. When Substance P binds to NK1 receptors in the brain's vomiting center, it triggers the sensation of nausea and the act of vomiting. Fosaprepitant, administered intravenously, acts as a prodrug, rapidly converting to aprepitant in the body. Aprepitant then selectively blocks these NK1 receptors, preventing Substance P from binding and thus interrupting the signaling pathway that leads to CINV. This targeted action helps to significantly reduce the incidence and severity of nausea and vomiting.

Typical Costs of Fosaprepitant

As a specialized intravenous medication used in oncology, fosaprepitant can be quite expensive. The typical cost can vary widely based on the specific dosage, the healthcare setting where it's administered, and whether it's the brand-name product or a generic version. Without insurance, a single dose could range from several hundreds to well over a thousand dollars. These costs do not include administration fees or other medications often given alongside it. It's a significant financial consideration for many patients and their families.

The information above is for educational purposes only and does not constitute medical advice. Consult your healthcare provider before making medication decisions.

What Fosaprepitant is approved for (FDA label)

Fosaprepitant for injection, in combination with other antiemetic agents, is indicated in adults and pediatric patients 6 months of age and older for the prevention of: • acute and delayed nausea and vomiting associated with initial and repeat courses of highly emetogenic cancer chemotherapy (HEC) including high-dose cisplatin. • delayed nausea and vomiting associated with initial and repeat courses of moderately emetogenic cancer chemotherapy (MEC). Limitations of Use • Fosaprepitant for injection has not been studied for the treatment of established nausea and vomiting.

Source: Read the full FDA label on DailyMed. Label effective date: August 15, 2026.

Excerpt from the FDA-approved prescribing information. This is not medical advice; talk to your doctor or pharmacist.

Dosage forms and strengths for Fosaprepitant (FDA label)

Fosaprepitant for Injection is available in a single dose glass vial containing 150 mg of fosaprepitant as a white to off-white fine fluffy powder or dry cake for reconstitution. Fosaprepitant for injection: 150 mg fosaprepitant, lyophilized powder in a single dose vial for reconstitution. ( 3 )

Source: FDA prescribing information (DailyMed). Set ID: 9b6d5ea3-2f7a-4501-9a4a-6fa1a7c2d50a. SPL document ID: 9e8e632e-726d-4c21-a657-c60ddfe1462f. Label effective date: August 15, 2026. Read the full label.

Excerpt from the FDA-approved prescribing information. This is not medical advice; talk to your doctor or pharmacist.

Adverse reactions for Fosaprepitant (FDA label)

The following clinically significant adverse reactions are described elsewhere in the labeling: • Hypersensitivity Reactions [see Warnings and Precautions (5.2) ] • Infusion Site Reactions [see Warnings and Precautions (5.3) ] • Most common adverse reactions in adults (≥ 2%) are: fatigue, diarrhea, neutropenia, asthenia, anemia, peripheral neuropathy, leukopenia, dyspepsia, urinary tract infection, pain in extremity. ( 6.1 ) • Adverse reactions in pediatrics are similar to adults.

Source: FDA prescribing information (DailyMed). Set ID: 9b6d5ea3-2f7a-4501-9a4a-6fa1a7c2d50a. SPL document ID: 9e8e632e-726d-4c21-a657-c60ddfe1462f. Label effective date: August 15, 2026. Read the full label.

Excerpt from the FDA-approved prescribing information. This is not medical advice; talk to your doctor or pharmacist.

Contraindications for Fosaprepitant (FDA label)

Fosaprepitant is contraindicated in patients: • who are hypersensitive to any component of the product. Hypersensitivity reactions including anaphylactic reactions, flushing, erythema, and dyspnea have been reported [see Warnings and Precautions (5.2) , Adverse Reactions (6.2) ] . • taking pimozide. Inhibition of CYP3A4 by aprepitant, the active moiety, could result in elevated plasma concentrations of this drug, which is a CYP3A4 substrate, potentially causing serious or life-threatening reactions, such as QT prolongation, a known adverse reaction of pimozide [see Warnings and Precautions (5.1) ] . • Known hypersensitivity to any component of this drug. ( 4 , 5.2 ) • Concurrent use with pimozide. ( 4 )

Source: FDA prescribing information (DailyMed). Set ID: 9b6d5ea3-2f7a-4501-9a4a-6fa1a7c2d50a. SPL document ID: 9e8e632e-726d-4c21-a657-c60ddfe1462f. Label effective date: August 15, 2026. Read the full label.

Excerpt from the FDA-approved prescribing information. This is not medical advice; talk to your doctor or pharmacist.

Warnings and precautions for Fosaprepitant (FDA label)

• CYP3A4 Interactions: Fosaprepitant is a weak inhibitor of CYP3A4, and aprepitant, the active moiety, is a substrate, inhibitor, and inducer of CYP3A4; see Full Prescribing Information for recommendations regarding contraindications, risk of adverse reactions, and dosage adjustment of fosaprepitant and concomitant drugs. ( 4 , 5.1 , 7.1 , 7.2 ) • Hypersensitivity Reactions (including anaphylaxis and anaphylactic shock): May occur during or soon after infusion. If symptoms occur, discontinue the drug. Do not reinitiate fosaprepitant if symptoms occur with previous use. ( 4 , 5.2 ) • Infusion Site Reactions (including thrombophlebitis, necrosis, and vasculitis): Majority of reactions reported in patients receiving vesicant chemotherapy. Avoid infusion into small veins.

Source: FDA prescribing information (DailyMed). Set ID: 9b6d5ea3-2f7a-4501-9a4a-6fa1a7c2d50a. SPL document ID: 9e8e632e-726d-4c21-a657-c60ddfe1462f. Label effective date: August 15, 2026. Read the full label.

Excerpt from the FDA-approved prescribing information. This is not medical advice; talk to your doctor or pharmacist.

Drug interactions for Fosaprepitant (FDA label)

See Full Prescribing Information for a list of clinically significant drug interactions. ( 4 , 5.1 , 5.4 , 5.5 , 7.1 , 7.2 ) 7.1 Effect of Fosaprepitant/Aprepitant on the Pharmacokinetics of Other Drugs When administered intravenously, fosaprepitant, a prodrug of aprepitant, is converted to aprepitant within 30 minutes. Therefore, drug interactions following administration of fosaprepitant for injection are likely to occur with drugs that interact with oral aprepitant. Fosaprepitant, given as a single 150 mg dose, is a weak inhibitor of CYP3A4, and the weak inhibition of CYP3A4 continues for 2 days after single dose administration.

Source: FDA prescribing information (DailyMed). Set ID: 9b6d5ea3-2f7a-4501-9a4a-6fa1a7c2d50a. SPL document ID: 9e8e632e-726d-4c21-a657-c60ddfe1462f. Label effective date: August 15, 2026. Read the full label.

Excerpt from the FDA-approved prescribing information. This is not medical advice; talk to your doctor or pharmacist.