EMEND
Clinical safety rating: caution
Comprehensive clinical and safety monograph for EMEND (EMEND).
Selective substance P/neurokinin 1 (NK1) receptor antagonist, which inhibits the binding of substance P in the emetic pathway.
| Metabolism | Primarily metabolized by CYP3A4; minor contributions from CYP1A2 and CYP2C19. |
| Excretion | Primarily metabolized; ~5% unchanged in urine, ~57% in feces as metabolites, ~32% in urine as metabolites. Renal elimination of parent drug is minimal. |
| Half-life | 9–13 hours (terminal) in healthy adults; clinically, this supports once-daily dosing. In patients with severe renal impairment (CrCl <30 mL/min), half-life is prolonged to ~16 hours. |
| Protein binding | >95% bound to plasma proteins, primarily albumin. |
| Volume of Distribution | Approximately 0.7–0.9 L/kg (70 L in a 70 kg adult), indicating extensive extravascular distribution. |
| Bioavailability | Oral: approximately 60–65% (due to first-pass metabolism). Intravenous: 100%. |
| Onset of Action | Oral: Within 1–2 hours (Cmax at 4 hours, but antiemetic effect by 1 hour). Intravenous: Immediate, with peak effect within 5–15 minutes. |
| Duration of Action | Oral: Antiemetic effect lasts up to 24 hours; a single dose covers the acute and delayed phases of chemotherapy-induced nausea and vomiting (CINV). IV: Duration similar, ~24 hours. |
| Action Class | NK1 Antagonists |
| Brand Substitutes | Fosa 150mg Injection, Fosaran 150mg Injection, Amitant-IV Injection, FOSapretero Injection, Artepitant 150mg Injection, Apritech 125/80 Capsule, Aprecap 125/80 Capsule, Emvoid 125 mg/80 mg Capsule, Apry 125mg/80mg Capsule, Empov 125mg/80mg Capsule |
125 mg orally once 1 hour before chemotherapy; then 80 mg orally once daily on Days 2 and 3.
| Dosage form | FOR SUSPENSION |
| Renal impairment | No dose adjustment required for any degree of renal impairment including end-stage renal disease (ESRD) on hemodialysis. |
| Liver impairment | Mild to moderate hepatic impairment (Child-Pugh score 5-9): no dose adjustment. Severe hepatic impairment (Child-Pugh score >9): no clinical studies; use with caution. |
| Pediatric use | For patients aged 6 months and older: Day 1: 3 mg/kg (max 125 mg) orally 1 hour before chemotherapy; Days 2 and 3: 2 mg/kg (max 80 mg) orally once daily. |
| Geriatric use | No specific dose adjustment required; pharmacokinetics similar to younger adults. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Comprehensive clinical and safety monograph for EMEND (EMEND).
| Breastfeeding | Excreted in rat milk; no human data. M/P ratio not established. Theoretical risk of infant exposure; manufacturer recommends discontinue breastfeeding or drug based on importance to mother. |
| Teratogenic Risk | FDA Pregnancy Category D. First trimester: Aprepitant crosses placenta; fetal malformations (e.g., cleft palate) observed in animal studies at subtherapeutic doses. Second/third trimesters: Limited human data; potential for fetal harm, especially with repeated use. Risk may be dose-dependent. |
| Fetal Monitoring |
■ FDA Black Box Warning
No FDA boxed warning.
| Serious Effects |
Hypersensitivity to any component; concomitant use with pimozide.
| Precautions | Reduced efficacy of oral contraceptives; potential for drug interactions with CYP3A4 substrates; hypersensitivity reactions including anaphylaxis; use in pregnancy only if clearly needed. |
Loading safety data…
| Monitor for fetal growth and development via ultrasound; assess for teratogenic effects if exposed during first trimester. No specific maternal monitoring required beyond standard prenatal care. |
| Fertility Effects | No significant impairment of fertility in animal studies at clinically relevant doses. Human data limited; no known adverse effects on spermatogenesis or ovulation. |