Fosaprepitant Dosage

• Dosage of Fosaprepitant in details
• Fosaprepitant interactions
• Fosaprepitant reviews

Dosage of Fosaprepitant in details

Prevention of Nausea and Vomiting Associated with HEC and MEC in Adult Patients

The recommended dosage of Fosaprepitant for Injection, dexamethasone, and a 5-HT3 antagonist for the prevention of nausea and vomiting associated with administration of HEC or MEC in adults is shown in Table 1 or Table 2, respectively. Administer Fosaprepitant for Injection as an intravenous infusion on Day 1 over 20 to 30 minutes, completing the infusion approximately 30 minutes prior to chemotherapy.

Pediatric use information is approved for Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc.’s Emend (Fosaprepitant) for injection. However, due to Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc.’s marketing exclusivity rights, this drug product is not labeled with that pediatric information.

Preparation of Fosaprepitant for Injection

Caution: Do not mix or reconstitute Fosaprepitant for Injection with solutions for which physical and chemical compatibility have not been established. Fosaprepitant for Injection is incompatible with any solutions containing divalent cations (e.g., Ca2+, Mg2+), including Lactated Ringer’s Solution and Hartmann's Solution.

Storage

The reconstituted final drug solution is stable for 24 hours at ambient room temperature [at or below 25°C (77°F)].

Pediatric use information is approved for Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc.’s Emend (Fosaprepitant) for injection. However, due to Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc.’s marketing exclusivity rights, this drug product is not labeled with that pediatric information.

What other drugs will affect Fosaprepitant?

Many drugs can interact with Fosaprepitant. Not all possible interactions are listed here. Tell your doctor about all your medications and any you start or stop using during treatment with Fosaprepitant, especially:

• everolimus;

• tolbutamide;

• warfarin, Coumadin;

• an antibiotic--clarithromycin, telithromycin;

• an antidepressant--nefazodone, paroxetine;

• antifungal medication--itraconazole, ketoconazole;

• HIV/AIDS medication--atazanavir, delavirdine, efavirenz, fosamprenavir, indinavir, nelfinavir, nevirapine, ritonavir, saquinavir;

• seizure medication--carbamazepine, phenytoin; or

• tuberculosis medication--rifabutin, rifampin, rifapentine.

This list is not complete and many other drugs can interact with Fosaprepitant. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.

Fosaprepitant interactions

ARIPiprazole: CYP3A4 Inhibitors (Weak) may increase the serum concentration of ARIPiprazole. Management: Monitor for increased aripiprazole pharmacologic effects. Aripiprazole dose adjustments may or may not be required based on concomitant therapy and/or indication. Consult full interaction monograph for specific recommendations. Monitor therapy

Astemizole: Fosaprepitant may increase the serum concentration of Astemizole. The active metabolite aprepitant is likely responsible for this effect. Avoid combination

Bosentan: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Clofazimine: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Conivaptan: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

Corticosteroids (Systemic): Fosaprepitant may increase the serum concentration of Corticosteroids (Systemic). The active metabolite aprepitant is likely responsible for this effect. Management: Decrease oral dexamethasone or methylprednisolone dose by 50% during coadministration with Fosaprepitant/aprepitant. Reduce intravenous methylprednisolone dose by 25% during coadministration with Fosaprepitant/aprepitant. Consider therapy modification

CYP3A4 Inducers (Moderate): May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

CYP3A4 Inducers (Strong): May decrease the serum concentration of Fosaprepitant. Specifically, CYP3A4 Inducers (Strong) may decrease serum concentrations of the active metabolite aprepitant. Avoid combination

CYP3A4 Inhibitors (Moderate): May increase the serum concentration of Fosaprepitant. Avoid combination

CYP3A4 Inhibitors (Strong): May increase the serum concentration of Fosaprepitant. Avoid combination

CYP3A4 Substrates (High risk with Inhibitors): Fosaprepitant may increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Dabrafenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Seek alternatives to the CYP3A4 substrate when possible. If concomitant therapy cannot be avoided, monitor clinical effects of the substrate closely (particularly therapeutic effects). Consider therapy modification

Deferasirox: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Dofetilide: CYP3A4 Inhibitors (Weak) may increase the serum concentration of Dofetilide. Monitor therapy

Erdafitinib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Erdafitinib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Estrogen Derivatives (Contraceptive): Fosaprepitant may decrease the serum concentration of Estrogen Derivatives (Contraceptive). The active metabolite aprepitant is likely responsible for this effect. Management: Alternative or additional methods of contraception should be used both during treatment with Fosaprepitant or aprepitant and for at least one month following the last Fosaprepitant/aprepitant dose. Consider therapy modification

Flibanserin: CYP3A4 Inhibitors (Weak) may increase the serum concentration of Flibanserin. Monitor therapy

Fusidic Acid (Systemic): May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

Idelalisib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

Ifosfamide: Fosaprepitant may increase the serum concentration of Ifosfamide. Specifically, concentrations of the toxic metabolites of ifosfamide may increase. Monitor therapy

Ivosidenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Larotrectinib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Lemborexant: CYP3A4 Inhibitors (Weak) may increase the serum concentration of Lemborexant. Management: The maximum recommended dosage of lemborexant is 5 mg, no more than once per night, when coadministered with weak CYP3A4 inhibitors. Consider therapy modification

Lomitapide: CYP3A4 Inhibitors (Weak) may increase the serum concentration of Lomitapide. Management: Patients on lomitapide 5 mg/day may continue that dose. Patients taking lomitapide 10 mg/day or more should decrease the lomitapide dose by half. The lomitapide dose may then be titrated up to a max adult dose of 30 mg/day. Consider therapy modification

NiMODipine: CYP3A4 Inhibitors (Weak) may increase the serum concentration of NiMODipine. Monitor therapy

Palbociclib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

PARoxetine: May decrease serum concentrations of the active metabolite(s) of Fosaprepitant. Fosaprepitant may decrease the serum concentration of PARoxetine. Monitor therapy

Pimozide: Fosaprepitant may increase the serum concentration of Pimozide. The active metabolite aprepitant is likely responsible for this effect. Avoid combination

Progestins (Contraceptive): Fosaprepitant may decrease the serum concentration of Progestins (Contraceptive). The active metabolite aprepitant is likely responsible for this effect. Management: Alternative or additional methods of contraception should be used both during treatment with aprepitant or Fosaprepitant and for at least one month following the last aprepitant/Fosaprepitant dose. Consider therapy modification

Sarilumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Siltuximab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Simeprevir: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Stiripentol: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Management: Use of stiripentol with CYP3A4 substrates that are considered to have a narrow therapeutic index should be avoided due to the increased risk for adverse effects and toxicity. Any CYP3A4 substrate used with stiripentol requires closer monitoring. Consider therapy modification

Terfenadine: Fosaprepitant may increase the serum concentration of Terfenadine. The active metabolite aprepitant is likely responsible for this effect. Avoid combination

Tocilizumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

TOLBUTamide: Fosaprepitant may decrease the serum concentration of TOLBUTamide. Monitor therapy

Triazolam: CYP3A4 Inhibitors (Weak) may increase the serum concentration of Triazolam. Management: Consider triazolam dose reduction in patients receiving concomitant weak CYP3A4 inhibitors. Consider therapy modification

Ubrogepant: CYP3A4 Inhibitors (Weak) may increase the serum concentration of Ubrogepant. Management: In patients taking weak CYP3A4 inhibitors, the initial and second dose (if needed) of ubrogepant should be limited to 50 mg. Consider therapy modification

Warfarin: Fosaprepitant may decrease the serum concentration of Warfarin. The active metabolite aprepitant is likely responsible for this effect. Monitor therapy

References

1. DailyMed. "FOSAPREPITANT DIMEGLUMINE: DailyMed provides trustworthy information about marketed drugs in the United States. DailyMed is the official provider of FDA label information (package inserts).". https://dailymed.nlm.nih.gov/dailyme... (accessed September 17, 2018).
2. FDA/SPL Indexing Data. "6L8OF9XRDC: The UNique Ingredient Identifier (UNII) is an alphanumeric substance identifier from the joint FDA/USP Substance Registration System (SRS).". https://www.fda.gov/ForIndustry/Data... (accessed September 17, 2018).
3. MeSH. "Neurokinin-1 Receptor Antagonists". https://www.ncbi.nlm.nih.gov/mesh/68... (accessed September 17, 2018).

Reviews

User reports

Consumer reviews

Information checked by Dr. Sachin Kumar, MD Pharmacology