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

The Cyanokit (hydroxocobalamin for injection) shortage has been an active challenge for emergency medicine professionals since it emerged in late 2024. For providers — including emergency physicians, medical toxicologists, EMS medical directors, hospital pharmacists, and ICU clinicians — the shortage demands proactive inventory management, updated clinical protocols, and a clear understanding of alternative treatment strategies.

This guide covers everything providers need to know in 2026: current shortage status, clinical alternatives, dosing considerations, procurement strategies, and how to prepare your facility before a cyanide poisoning emergency occurs.

Current Shortage Status and Root Cause

The ASHP Drug Shortage Resource Center has listed hydroxocobalamin for injection (Cyanokit) as having "limited availability" since late 2024, with no anticipated resolution date from the manufacturer as of late 2025. The root cause is a quality defect at SERB Pharmaceuticals' contract manufacturer — specifically, concerns about sterility assurance and endotoxin content led to a manufacturing suspension.

The FDA released some impacted batches with the guidance that providers should use a 0.2-micron in-line filter during administration to mitigate potential sterility concerns. Providers should verify that their available stock's lot numbers appear on the FDA advisory and follow the filter recommendation.

Key structural vulnerability: There is only one manufacturer of the Cyanokit 5g IV formulation in the U.S. market, and there is no FDA-approved generic alternative. This single-source dependency means any manufacturing disruption has immediate, nationwide impact.

Clinical Background: Why Hydroxocobalamin Is the Preferred Antidote

Cyanide acts by binding cytochrome a3 in the mitochondrial electron transport chain, halting ATP production and forcing anaerobic metabolism. The result is a profound lactic acidosis and rapid cellular hypoxia despite normal arterial oxygen saturation. Signs — including altered mental status, seizures, hypotension, and cardiac arrest — can progress within minutes of significant exposure.

Hydroxocobalamin counters this by binding cyanide in a 1:1 molar ratio, forming cyanocobalamin (vitamin B12), which is renally cleared. It has several clinically important advantages over the older nitrite-thiosulfate approach:

• No methemoglobinemia: Does not reduce hemoglobin oxygen-carrying capacity. Safe for patients with concurrent CO poisoning — the most common real-world scenario.
• Hemodynamic support: Binds nitric oxide, contributing to vasoconstriction — can be beneficial in cyanide-induced hypotension.
• Safe in G6PD deficiency and anemia: Unlike sodium nitrite, hydroxocobalamin does not induce additional oxidative stress on red blood cells.
• Prehospital compatible: Can be administered in the field, enabling earlier antidotal therapy before hospital arrival.

Dosing Reference (Adults)

When Cyanokit is available, standard adult dosing is: 5g (one vial) IV infusion over 15 minutes. If needed based on severity and clinical response, a second 5g dose may be given — at a rate ranging from 15 minutes (patient in extremis) to 2 hours — for a total maximum of 10g. Reconstitute with 200 mL 0.9% NaCl (or Lactated Ringer's or D5W if NS unavailable). Diluent is NOT included in the kit.

Alternative Treatment Protocols During the Shortage

When Cyanokit supply is exhausted or unavailable, the following framework should guide alternative therapy selection:

Smoke inhalation victims (likely concurrent CO poisoning): Administer sodium thiosulfate 12.5g IV immediately. Avoid sodium nitrite due to methemoglobinemia risk in CO-exposed patients. If patient remains critically ill with persistent coma, seizures, refractory acidemia (lactate >10 mmol/L), or dysrhythmias, consider sodium nitrite with continuous BP monitoring.

Non-fire industrial/occupational exposure: Nithiodote (sodium nitrite 300 mg IV + sodium thiosulfate 12.5g IV sequentially) is appropriate. Monitor blood pressure continuously during sodium nitrite infusion. Repeat at half doses if toxicity recurs.

Cyanide salt ingestion (intact airway): Activated charcoal 1g/kg if patient is alert and can protect airway, followed by Nithiodote or sodium thiosulfate alone.

Pediatric dosing with Cyanokit: Based on non-U.S. experience, 70 mg/kg IV (maximum 5,000 mg/dose) has been used. No U.S. pediatric safety and efficacy studies have been conducted.

Important Drug Incompatibilities

If administering Cyanokit alongside other resuscitation drugs, be aware of critical incompatibilities. The following must NOT be administered in the same IV line as hydroxocobalamin:

• Sodium thiosulfate (chemical incompatibility — forms thiosulfatocobalamin)
• Sodium nitrite
• Diazepam, dopamine, dobutamine

Use separate IV lines for any coadministered agents. Hydroxocobalamin's dark red color will also interfere with colorimetric laboratory tests (bilirubin, creatinine kinase, creatinine, glucose, magnesium) and may trigger false alarms on hemodialysis blood-leak detectors.

Procurement Strategies for Providers

Hospital pharmacists and EMS purchasing directors should pursue multiple channels simultaneously to secure available Cyanokit stock:

1. Check ASHP Drug Shortage Center weekly for updated lot advisories and anticipated resolution dates
2. Contact primary distributor (McKesson, Cardinal Health, AmerisourceBergen) for allocation status
3. Contact SERB Pharmaceuticals' Specialty Solutions Center directly (1-877-377-3784)
4. Check specialty EMS suppliers (Life-Assist, Bound Tree Medical) for separate allocation channels
5. Use medfinder for providers to efficiently locate available supply across multiple channels without manual calling

Key Takeaways for Emergency Providers in 2026

• Cyanokit remains the preferred cyanide antidote; use available stock for high-probability cases and supplement with backup protocols
• Available Cyanokit from impacted batches can be used with a 0.2-micron in-line filter per FDA guidance
• Sodium thiosulfate alone is the safest alternative for smoke inhalation victims; avoid sodium nitrite in CO-poisoned patients
• Always consult your regional poison control center (1-800-222-1222) for real-time clinical guidance
• Audit your antidote stock regularly and do not wait until an emergency to check availability