Emend Shortage: What Providers and Prescribers Need to Know in 2026

For oncologists, pharmacists, and other prescribers managing CINV prevention protocols, the supply volatility of Emend (aprepitant) has required clinical adaptation in recent years. This article provides a comprehensive review of the shortage history, current availability landscape, and evidence-based alternatives to support optimal patient care in 2026.

Current Shortage Status (2026)

Emend is not currently on the FDA's active drug shortage list as of 2026. The EMA documented a shortage of Emend powder for oral suspension (80 mg and 125 mg), first published April 2024, which was resolved as of October 2025. In the U.S., generic aprepitant is available from multiple manufacturers, which has substantially improved national supply reliability.

However, clinicians should not assume consistent local availability. Retail pharmacy stock remains uneven, particularly for the oral suspension (used in pediatric patients aged 6 months and older) and the 125 mg starting dose. Practices near major academic medical centers may be less affected due to specialty pharmacy access; community oncology practices should proactively verify supply before each treatment cycle.

Shortage Etiology: What Happened and Why

The ASHP documented the shortage of Emend oral capsules, attributing it to increased demand—Merck, at that time, was the sole supplier. This single-source dependency created systemic vulnerability. When demand accelerated—driven in part by expanded use across oncology protocols and broader application of CINV prophylaxis guidelines—the supply chain could not rapidly scale.

The injectable fosaprepitant (Emend for Injection) was not impacted by the capsule shortage, offering an important clinical workaround for inpatient and infusion center settings. Generic entry into the market has since diversified supply, though the generic oral suspension market remains thin.

Clinical Alternatives: Evidence and Guideline Support

When aprepitant is unavailable, several guideline-endorsed alternatives should be considered based on the patient's chemotherapy emetogenicity and comedication profile:

Rolapitant (Varubi)

Rolapitant is a highly selective NK1 receptor antagonist with an approximately 180-hour half-life, enabling single-dose administration (180 mg orally, 1-2 hours before chemotherapy). Unlike aprepitant, rolapitant does not inhibit or induce CYP3A4, eliminating the need for dexamethasone dose adjustments—a meaningful clinical simplification. Rolapitant does inhibit CYP2D6, which warrants caution with narrow-therapeutic-index CYP2D6 substrates (notably pimozide and thioridazine, which are contraindicated).

Phase III data support rolapitant's efficacy in both HEC and MEC settings when combined with granisetron and dexamethasone. CR rates in the delayed phase were significantly higher compared to control in three pivotal trials enrolling approximately 2,500 patients.

Netupitant-Palonosetron (NEPA / Akynzeo)

NEPA combines netupitant (300 mg NK1 antagonist) with palonosetron (0.5 mg, second-generation 5-HT3 antagonist) in a single oral capsule. A meta-analysis published in The Oncologist found NEPA-based regimens showed superior efficacy over aprepitant-based regimens for controlling delayed and overall-phase CINV in moderately emetogenic chemotherapy. Netupitant has an approximately 80-hour half-life. Like aprepitant, netupitant is a CYP3A4 substrate and moderate inhibitor—dexamethasone dose adjustment remains necessary. NEPA is listed in ASCO, NCCN, and MASCC/ESMO antiemetic guidelines as a preferred NK1 + 5-HT3 combination.

Fosaprepitant (Emend for Injection)

Fosaprepitant 150 mg IV on Day 1 is guideline-equivalent to the 3-day oral aprepitant regimen for Day 1 coverage. It is typically administered over 30 minutes, 30 minutes before chemotherapy. For patients who cannot tolerate oral medications or where oral aprepitant is unavailable, fosaprepitant remains the most pharmacologically direct substitute.

Note: Infusion-site reactions (including thrombophlebitis and vesicant-related complications) occur at a higher incidence with fosaprepitant (approximately 3%) compared to oral aprepitant (approximately 0.5%). Exercise caution in patients receiving concurrent vesicant chemotherapy, particularly anthracyclines.

Olanzapine as an Augmenting Agent

Current ASCO and NCCN guidelines recommend a 4-drug regimen (NK1 antagonist + 5-HT3 antagonist + dexamethasone + olanzapine) for HEC. In situations where NK1 availability is constrained, olanzapine (typically 10 mg daily on days 1-4) in combination with a 5-HT3 antagonist and dexamethasone provides meaningful antiemetic coverage. A phase III NCCN-sponsored trial (URCC CCOP N10C2) demonstrated that adding olanzapine significantly improved both nausea and vomiting control in HEC, with 74% of patients achieving no nausea on day 1 versus 45% in the control arm.

Managing Drug Interactions When Switching from Aprepitant

A key consideration when switching from aprepitant to a non-CYP3A4-interacting NK1 antagonist (rolapitant) is adjusting dexamethasone dosing back to the standard dose. Because aprepitant increases dexamethasone exposure by approximately 50% (oral) via CYP3A4 inhibition, prescribers typically reduce dexamethasone by 50% during aprepitant co-administration. When switching to rolapitant, dexamethasone may be given at full protocol dose without adjustment.

Similarly, patients on warfarin require INR monitoring 7-10 days after each aprepitant-containing cycle due to CYP2C9 induction, which decreases warfarin exposure. This monitoring requirement does not apply to rolapitant.

Practical Recommendations for 2026

Verify stock proactively. Confirm pharmacy availability 3-5 business days before each treatment cycle, particularly for community-based patients.

Have an approved alternative on the protocol. Pre-authorize rolapitant or NEPA as alternatives in your standing order sets so clinicians can substitute quickly without delays.

Leverage your infusion center pharmacy. Fosaprepitant via the infusion center eliminates the retail pharmacy search entirely for Day 1 coverage.

Recommend medfinder to patients. For patients sourcing medications from retail pharmacies, medfinder calls pharmacies on their behalf to locate availability, reducing appointment-day stress.

A Note on Pediatric Patients

The aprepitant oral suspension (for patients ≥6 months) remains challenging to source at standard retail pharmacies. Pediatric oncology patients should receive their prescriptions through the treating institution's pharmacy. For community pediatric oncologists managing outpatient CINV protocols, building a relationship with a specialty pharmacy that reliably stocks the suspension is essential. For more resources for prescribers, visit medfinder for providers.