HomeNDC LookupIngredientsHydroxocobalamin › 50633-0310-11
Cyanokit Hydroxocobalamin 5 g/250mL Injection, Powder, Lyophilized, For Solution — NDC 50633-0310-11 package photo

Cyanokit Hydroxocobalamin 5 g/250mL Injection, Powder, Lyophilized, For Solution

by BTG INTERNATIONAL INC. · 1 VIAL, GLASS in 1 CARTON (50633-310-11) / 250 mL in 1 VIAL, GLASS
NDC 50633-0310-11
🏷️ FDA NDC (as labeled) 50633-310-11 billing pads the product segment with a zero
Rx only Brand On market Non-controlled ⚠ On shortage
🗂️ Data synced Jul 24, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →
⚠️
Active FDA shortage. Hydroxocobalamin Injection is currently reported in shortage by the FDA (Other). Limited Availability Shortage details →

🆔 Identity & classification

FDA NDC (as labeled) 50633-310-11
Product NDC 50633-310
11-digit billing NDC 50633031011
NCPDP billing unit EA — each (per item)
RxCUI 700496, 700499
UNII Q40X8H422O
Application # NDA022041
SPL Set ID d56fcc8d-bd64-46ab-b0c0-2124bd745a6b
Established class (EPC) Antidote
DEA schedule Non-controlled
Marketing category NDA
Marketing status On market
FDA listing status Listed (active directory)
Marketing start 2021-12-15
Route INTRAVENOUS
Dosage form INJECTION, POWDER, LYOPHILIZED, FOR SOLUTION
Substance HYDROXOCOBALAMIN
GPI-14 93000047002110
GPI class Cyanokit
GCN Seq No 067836
GCN 30447
HICL code 001054
Ingredient (HICL) Hydroxocobalamin
HIC1 code C
Therapeutic class — broad (HIC1) Electrolyte Balance/Metabolism/Nutrition
HIC2 code C8
Therapeutic class — intermediate (HIC2) Antidotes To Poisons
HIC3 code C8E
Therapeutic class — specific (HIC3) Antidotes,Miscellaneous
AHFS code 91:00.00.00
AHFS class Antidote Therapeutics
FDB label name CYANOKIT 5 GRAM VIAL
FDB brand name Cyanokit
Legend status F — Federal legend — prescription drug or device
Why two NDCs? The FDA registers this code as 50633-310-11 — a 5-3-2 layout, and that's what's printed on the package and shown on DailyMed. For insurance claims, every NDC is standardized to a uniform 11-digit 5-4-2 format by adding a zero to the product segment → 50633-0310-11. Same drug, same package — only the format differs.
Where does this data come from?
Identifiers from the FDA openFDA NDC Directory and Structured Product Labeling; RxCUI from RxNorm (NLM); GPI from Medi-Span; GCN / HIC / AHFS / legend from First Databank.

🏷️ RxNorm drug class

This medicine belongs to the Antidote class.

Pharmacologic class Antidote
Drug family (ATC) Vitamin B12 (cyanocobalamin and analogues), Antidotes
Where does this data come from?
Therapeutic classes from RxNorm RxClass (U.S. National Library of Medicine) — Established Pharmacologic Class (FDA), ATC drug family (WHO) and mechanism of action, matched by this product’s RxCUI.

🏭 Manufacturer & labeler

LabelerBTG INTERNATIONAL INC.
Application holderBTG INTERNATIONAL INC
FDA applicationNDA022041 (NDA)
Labeler code50633
First marketedDec 2021
Product typeHuman Prescription Drug
Portfolio6 products on file
The labeler markets the product; the application holder owns the FDA approval. They’re often the same company but can differ (e.g. a repackager or an authorized generic). A mailing address / phone appears here when the manufacturer includes it in the product’s FDA label (not all do).
Where does this data come from?
Labeler, application holder and registered establishment from the FDA openFDA NDC Directory and Drugs@FDA; address/contact from the product’s FDA label.

🩺 Clinical

Label name CYANOKIT 5 GRAM VIAL Ingredient Hydroxocobalamin
📖 What it is MedlinePlus · NLM

Cyanocobalamin injection is used to treat and prevent a lack of vitamin B12 that may be caused by any of the following: pernicious anemia (lack of a natural substance needed to absorb vitamin B12 from the intestine); certain diseases, infections, or medications that decrease the amount of vitamin B12 absorbed from food; or a vegan diet (strict vegetarian diet that does not allow any animal products, including dairy products and eggs). Lack of vitamin B12 may cause anemia (condition in which the red blood cells do not bring enough oxygen to the organs) and permanent damage to the nerves. Cyanoc...

Read the full MedlinePlus article ↗
Where does this data come from?
Plain-language summary from MedlinePlus (U.S. National Library of Medicine); supplement & herbal interactions and nutrient depletion data from the Natural Medicines database; our full guide is HelloPharmacist editorial content.

🧪 Inactive Ingredients / Excipients

Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.

💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.

  • UNII QTT17582CB
    A strong acid used to adjust and maintain the proper pH level in liquid medicines, ensuring stability and preventing breakdown of active ingredients.

1 inactive ingredient listed in the exact product block matched to this NDC.

Where does this data come from?
Data sourced from official FDA Structured Product Labeling (SPL) via DailyMedingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.

Inactive ingredient FAQ

Are inactive ingredients the same for every manufacturer?
No. Inactive ingredients can differ by manufacturer, dosage form, strength, and package / product version.
Why might an inactive ingredient be missing?
Some SPLs do not provide a complete structured inactive-ingredient list, and older or unusual labels may only include the information in narrative text.
Can inactive ingredients matter?
Yes. They can matter for allergies, intolerances, dyes, gluten / lactose concerns, preservatives, and formulation differences — but confirm with a pharmacist or the manufacturer when it’s clinically important.

💲 Pricing

A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.

Price systemPer mLPer package
Retail pharmacies payNADAC · weekly Not in the retail survey — common for institutional, discontinued, or low-volume packs.
Medicaid paysCMS SDUD · 12 mo No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data.
Medicare drug plans payPart D · quarterly No Part D plan price is available for this NDC in our data.
Medicare Part B allowsASP · J3424 No ASP payment limit on file for J3424 this quarter.
ℹ️
No price is published for this exact package yet. CMS surveys NADAC per package size, so a different pack of the same drug often has one.
Where does this data come from?
NADAC (National Average Drug Acquisition Cost) is the CMS weekly pharmacy-acquisition-cost survey — what pharmacies pay. ASP (Average Sales Price) is the CMS Medicare Part B drug-payment file, published quarterly. Medicaid pays is computed by us from CMS State Drug Utilization Data (total reimbursed ÷ units, trailing 12 months) — gross of rebates and inclusive of dispensing fees, so it reflects what Medicaid paid, not an acquisition cost. Medicare drug plans pay is the median negotiated point-of-sale unit cost across plans listing this NDC in the CMS quarterly Prescription Drug Plan pricing files, before rebates. The VA pays is the federal contract price (FSS, and the statutory Big 4 ceiling where listed) from the VA National Acquisition Center pharmaceutical price file. All are free public government data; each measures a different payer, so the figures are not directly comparable.

🧾 Billing & reimbursement

FDA NDC (as labeled)50633-310-11
11-digit billing NDC50633-0310-11
Format5-3-2 as registered → padded to 5-4-2 for billing (zero added to the product segment)
HCPCS J-codeJ3424
DescriptorINJECTION, HYDROXOCOBALAMIN, INTRAVENOUS, 25 MG
Billing units / pkg200 units
Crosswalk sourcePDAC NDC-HCPCS crosswalk (DME MAC / DMEPOS)
Where does this data come from?
The HCPCS J-code crosswalk comes from the CMS ASP NDC-HCPCS crosswalk and the DMEPDAC (DME MAC) NDC-HCPCS crosswalk — free public CMS data. Billing units are derived from the code’s descriptor and the package amount.

🔁 Therapeutic equivalents

ProductLabelerPackNADAC/unitTEStatusPrice vs. this
Cyanokit 5 g/250mLthis 50633-0310-11 BTG 1 vial FDA listed
About this product: this is the brand-name version. We did not find an FDA-approved generic match for this exact strength, form and route.
Where does this data come from?
Equivalents are other NDCs of the same ingredient, form and route from the openFDA NDC Directory, ranked least-expensive-first by NADAC. Therapeutic-equivalence (AB) ratings come from the FDA Orange Book; biologics use the FDA Purple Book for biosimilar & interchangeable status.

Availability & generic status

🏛️
2021
On the market since
Dec 2021
📍
2026
Currently FDA-listed
5 years listed
🔒
·
No generic listed yet
brand only
ℹ️No FDA-approved generic found

We did not find an FDA-approved generic match for this exact strength, form and route.

Where does this data come from?
Patents and exclusivity from the FDA Orange Book (small-molecule drugs), refreshed from public FDA data. Generic launch timing is an estimate, not a guarantee.

📦 Packaging — all sizes for this product

Package NDCDescription Marketing startStatus
50633-0310-11 You're viewing this 1 VIAL, GLASS in 1 CARTON (50633-310-11) / 250 mL in 1 VIAL, GLASS 2021-12-15 Active

🧭 About this NDC listing & data coverage

Finished prescription product
What data is (and isn’t) available for this NDC — tap to expand
NDC identity (package / product / labeler codes) ✓ Available
Labeler ✓ Available
Product & package description ✓ Available
Marketing category & status ✓ Available
Active ingredient / dosage form / route ✓ Available
FDA label (SPL via DailyMed) ✓ Available
Package photos ✓ Available
Inactive ingredients (structured) ✓ Available
NADAC pharmacy acquisition price (CMS) — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey.
Orange Book / therapeutic-equivalence data — Not published for this NDC Applies only to products approved under an NDA/ANDA; many listings are out of scope.
HCPCS J-code billing crosswalk ✓ Available
Medicaid utilization (CMS SDUD) — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold.
“Not published” reflects what the public FDA / CMS / NLM sources provide for this exact package code — it is a property of the data feeds, not a judgment about the product.

Questions about this listing

Why is there no price listed?
The pricing shown on our NDC pages comes from CMS NADAC, a voluntary survey of retail community pharmacy invoices. CMS does not publish a NADAC for every NDC — packages outside the retail survey (institutional and hospital products, bulk packages, discontinued items, and many OTC items) may never receive one. A missing price reflects the survey's scope, not this product's actual cost, and does not mean the product is free or unavailable.
Is the NDC printed on the package the same as the 11-digit billing NDC?
Yes, they identify this exact package in different formats. The FDA registers it as 50633-310-11, which is what is printed on the packaging and shown on DailyMed. Insurance claims use a fixed 11-digit 5-4-2 format, so the short segment is padded with a leading zero: 50633-0310-11, written without dashes as 50633031011. The Identity section at the top of this page lists every form of this code.
What do the three segments of this NDC mean?
In 50633-0310-11, the first segment (50633) is the labeler code FDA assigned to BTG INTERNATIONAL INC.; the middle segment (0310) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (11) identifies this exact package size and type. Together they name one specific package of one specific product.
Is this package still being marketed?
Yes, per the latest FDA NDC Directory data on this page: this package is listed as actively marketed, with no marketing end date reported by BTG INTERNATIONAL INC.. Listing status can change — the directory data on this page refreshes weekly.
Who lists this product with the FDA?
BTG INTERNATIONAL INC. is the labeler of record for this NDC — the company under whose FDA-assigned code the package is listed. The labeler may be the manufacturer itself or a distributor marketing the product under its own code.
Do I need a prescription for this product?
This NDC is listed with FDA as a prescription product, so it is dispensed under a prescriber's order. Your pharmacist can tell you whether any over-the-counter forms of the same medication exist.
Does this product have a billing J-code?
Yes — this NDC cross-references HCPCS code J3424 for medical-claim billing (typically used when a product is administered in a clinical setting rather than dispensed at a retail pharmacy). See the Billing section on this page.
This page identifies an FDA-listed package (the NDC) and reports public regulatory and pricing data about the listing. It is reference information, not a medical recommendation — talk to your pharmacist or prescriber about your own medication.
Where does this data come from?
Listing facts (marketing category, packager status, marketing dates) from the FDA openFDA NDC Directory; label availability from DailyMed; pricing coverage from CMS NADAC; equivalence scope from the FDA Orange Book.

📄 Full prescribing information FDA SPL

The complete FDA label for this product — the official prescribing information, verbatim, section by section. Jump with a chip, search within the label, or expand everything.
🎯 Indications and Usage 31 words

1 INDICATIONS AND USAGE CYANOKIT is indicated for the treatment of known or suspected cyanide poisoning. CYANOKIT is indicated for the treatment of known or suspected cyanide poisoning. ( 1 )

⏱️ Dosage and Administration ~3 min read

2 DOSAGE AND ADMINISTRATION If clinical suspicion of cyanide poisoning is high, administer CYANOKIT without delay and in conjunction with appropriate airway, ventilatory, and circulatory support, oxygen administration as well as management of seizures. ( 2.1 ) The expert advice of a regional poison control center may be obtained by calling 1-800-222-1222. ( 2.1 ) Dosing : The starting dose of CYANOKIT for adults is 5 g, administered by intravenous infusion over 15 minutes.

One 5 g vial is a complete starting dose. ( 2.2 ) Depending upon the severity of the poisoning and the clinical response, a second dose of 5 g may be administered by intravenous infusion for a total dose of 10 g. ( 2.2 ) The rate of infusion for the second 5 g dose may range from 15 minutes (for patients in extremis) to 2 hours based on patient condition.

( 2.2 ) The recommended diluent is 0.9% Sodium Chloride injection. ( 2.3 ) CYANOKIT requires a separate intravenous line for administration. ( 2.4 )

2.1Important Dosage and Administration Instructions If clinical suspicion of cyanide poisoning is high, administer CYANOKIT without delay. Comprehensive treatment of acute cyanide intoxication requires support of vital functions. Airway, ventilatory and circulatory support, oxygen administration, and management of seizures should not be delayed to administer CYANOKIT [see Warnings and Precautions ( 5.1 )] .

The expert advice of a regional poison control center may be obtained by calling 1-800-222-1222. Identifying Patients with Cyanide Poisoning Cyanide poisoning may result from inhalation, ingestion, or dermal exposure to various cyanide-containing compounds, including smoke from closed-space fires. Sources of cyanide poisoning include hydrogen cyanide and its salts, cyanogenic plants, aliphatic nitriles, and prolonged exposure to sodium nitroprusside.

The presence and extent of cyanide poisoning are often initially unknown. There is no widely available, rapid, confirmatory cyanide blood test. Treatment decisions must be made on the basis of clinical history and signs and symptoms of cyanide intoxication.

Table 1 Common Signs and Symptoms of Cyanide Poisoning Symptoms Headache Confusion Dyspnea Chest tightness Nausea Signs Altered Mental Status (e.g., confusion, disorientation) Seizures or Coma Mydriasis Tachypnea / Hyperpnea (early) Bradypnea / Apnea (late) Hypertension (early) / Hypotension (late) Cardiovascular collapse Vomiting Plasma lactate concentration ≥8 mmol/L In some settings, panic symptoms including tachypnea and vomiting may mimic early cyanide poisoning signs. The presence of altered mental status (e.g., confusion and disorientation) and/or mydriasis is suggestive of true cyanide poisoning although these signs can occur with other toxic exposures as well.

Smoke Inhalation Not all smoke inhalation victims will have cyanide poisoning and may present with burns, trauma, and exposure to other toxic substances making a diagnosis of cyanide poisoning particularly difficult. Prior to administration of CYANOKIT, smoke-inhalation victims should be assessed for the following: Exposure to fire or smoke in an enclosed area Presence of soot around the mouth, nose or oropharynx Altered mental status Although hypotension is highly suggestive of cyanide poisoning, it is only present in a small percentage of cyanide-poisoned smoke inhalation victims.

Also indicative of cyanide poisoning is a plasma lactate concentration ≥10 mmol/L (a value higher than that typically listed in the table of signs and symptoms of isolated cyanide poisoning because carbon monoxide associated with smoke inhalation also contributes to lactic acidemia). If cyanide poisoning is suspected, treatment should not be delayed to obtain a plasma lactate concentration. Use with Other Cyanide Antidotes The safety of administering other cyanide antidotes simultaneously with CYANOKIT has not been established.

If a decision is made to administer another cyanide antidote with CYANOKIT, these drugs…

💊 Dosage Forms and Strengths 84 words

3 DOSAGE FORMS AND STRENGTHS CYANOKIT (hydroxocobalamin for injection) for intravenous infusion consists of 1 vial, containing 5 g lyophilized hydroxocobalamin dark red crystalline powder for injection. After reconstitution, the vial contains hydroxocobalamin for injection, 25 mg/mL [see How Supplied/Storage and Handling ( 16 ) for full kit description]. CYANOKIT (hydroxocobalamin for injection) for intravenous infusion consists of 1 vial, containing 5 g lyophilized hydroxocobalamin dark red crystalline powder for injection.

After reconstitution, the vial contains hydroxocobalamin for injection, 25 mg/mL. ( 3 )

Contraindications 7 words

4 CONTRAINDICATIONS None None ( 4 )

⚠️ Warnings and Cautions ~3 min read

5 WARNINGS AND PRECAUTIONS Risk of Anaphylaxis and Other Hypersensitivity Reactions : Consider alternative therapies, if available, in patients with known anaphylactic reactions to hydroxocobalamin or cyanocobalamin. ( 5.2 ) Risk of Renal Injury : Acute renal failure with acute tubular necrosis, renal impairment and urine calcium oxalate crystals have been reported following CYANOKIT therapy. Monitor renal function for 7 days following CYANOKIT therapy.

( 5.3 ) Risk of Increased Blood Pressure : Substantial increases in blood pressure may occur following CYANOKIT therapy. Monitor blood pressure during treatment. ( 5.4 )

5.1Emergency Patient Management In conjunction with CYANOKIT, treatment of cyanide poisoning must include immediate attention to airway patency, adequacy of oxygenation and hydration, cardiovascular support, and management of seizures. Consideration should be given to decontamination measures based on the route of exposure.

5.2Risk of Anaphylactic and Other Hypersensitivity Reactions Use caution in the management of patients with known anaphylactic reactions to hydroxocobalamin or cyanocobalamin. Consider alternative therapies, if available. Allergic reactions may include: anaphylaxis, chest tightness, edema, urticaria, pruritus, dyspnea, and rash. Allergic reactions including angioneurotic edema have also been reported in postmarketing experience.

5.3Risk of Renal Injury Cases of acute renal failure with acute tubular necrosis, renal impairment, and urine calcium oxalate crystals have been reported. In some situations, hemodialysis was required to achieve recovery. Regular monitoring of renal function, including but not limited to blood urea nitrogen (BUN) and serum creatinine, should be performed for 7 days following CYANOKIT therapy.

5.4Risk of Increased Blood Pressure Many patients with cyanide poisoning will be hypotensive; however, elevations in blood pressure have also been observed in known or suspected cyanide poisoning victims. Elevations in blood pressure (≥180 mmHg systolic or ≥110 mmHg diastolic) were observed in approximately 18% of healthy subjects (not exposed to cyanide) receiving hydroxocobalamin 5 g and 28% of subjects receiving 10 g. Increases in blood pressure were noted shortly after the infusions were started; the maximal increase in blood pressure was observed toward the end of the infusion.

These elevations were generally transient and returned to baseline levels within 4 hours of dosing. Monitor blood pressure during treatment with CYANOKIT.

5.5Interference with Clinical Laboratory Evaluations and Clinical Methods Clinical Laboratory Evaluations Because of its deep red color, hydroxocobalamin has been found to interfere with colorimetric determination of certain laboratory parameters (e.g., clinical chemistry, hematology, coagulation, and urine parameters). In vitro tests indicated that the extent and duration of the interference are dependent on numerous factors such as the dose of hydroxocobalamin, analyte, methodology, analyzer, hydroxocobalamin concentration, and partially on the time between sampling and measurement.

The data presented in Table 2 is collected from in vitro studies and pharmacokinetic data in healthy volunteers and describes laboratory interference that may be observed following a 5 g dose of hydroxocobalamin. Interference following a 10 g dose can be expected to last up to an additional 24 hours. The extent and duration of interference in cyanide-poisoned patients may differ.

In addition, results may vary substantially from one analyzer to another. Be aware of this when reporting and interpreting laboratory results. Table 2 Laboratory Interference Observed with in vitro Samples of Hydroxocobalamin Laboratory Parameter No Interference Observed Artificially Increased * Artificially Decreased * Un-predictable Duration of Interference * ≥10% interference observed on at least 1 analyzer Analyzers used: ACL Futura (Instrumentation Laboratory), AxSYM ® /Architect ™…

🤒 Adverse Reactions ~3 min read

6 ADVERSE REACTIONS Serious adverse reactions with hydroxocobalamin include allergic reactions, renal injury, and increases in blood pressure [see Warnings and Precautions ( 5.2 , 5.3 , 5.4 )]. Most common adverse reactions (>5%) include transient chromaturia, erythema, oxalate crystals in urine, rash, increased blood pressure, nausea, headache, and infusion site reactions. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS contact BTG at 1-877-377-3784, or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1Clinical Studies Experience Experience in Healthy Subjects Because clinical trials were conducted under widely varying conditions, adverse reaction rates observed in the clinical trials may not reflect the rates observed in practice. A double-blind, randomized, placebo-controlled, single-ascending-dose (2.5, 5, 7.5, and 10 g) study was conducted to assess the safety, tolerability, and pharmacokinetics of hydroxocobalamin in 136 healthy adult subjects. Because of the dark red color of hydroxocobalamin, the two most frequently occurring adverse reactions were chromaturia (red-colored urine) which was reported in all subjects receiving a 5 g dose or greater; and erythema (skin redness), which occurred in most subjects receiving a 5 g dose or greater.

Adverse reactions reported in at least 5% of the 5 g dose group and corresponding rates in the 10 g and placebo groups are shown in Table 3 . Table 3 Incidence of Adverse Reactions Occurring in >5% of Subjects in 5 g Dose Group and Corresponding Incidence in 10 g Dose Group and Placebo * Rashes were predominantly acneiform ADR 5 g Dose Group 10 g Dose Group Hydroxocobalamin N=66 n (%) Placebo N=22 n (%) Hydroxocobalamin N=18 n (%) Placebo N=6 n (%) Chromaturia (red colored urine) 66 (100) 0 18 (100) 0 Erythema 62 (94) 0 18 (100) 0 Oxalate crystals in urine 40 (61) 1 (5) 10 (56) 0 Rash* 13 (20) 0 8 (44) 0 Blood pressure increased 12 (18) 0 5 (28) 0 Nausea 4 (6) 1 (5) 2 (11) 0 Headache 4 (6) 1 (5) 6 (33) 0 Lymphocyte percent decreased 5 (8) 0 3 (17) 0 Infusion site reaction 4 (6) 0 7 (39) 0 In this study, the following adverse reactions were reported to have occurred in a dose-dependent fashion and with greater frequency than observed in placebo-treated cohorts: increased blood pressure (particularly diastolic blood pressure), rash, nausea, headache and infusion site reactions.

All were mild to moderate in severity and resolved spontaneously when the infusion was terminated or with standard supportive therapies. Other adverse reactions reported in this study and considered clinically relevant were: Eye disorders: swelling, irritation, redness Gastrointestinal disorders: dysphagia, abdominal discomfort, vomiting, diarrhea, dyspepsia, hematochezia General disorders and administration site conditions: peripheral edema, chest discomfort Immune system disorders: allergic reaction Nervous system disorders: memory impairment, dizziness Psychiatric disorders: restlessness Respiratory, thoracic and mediastinal disorders: dyspnea, throat tightness, dry throat Skin and subcutaneous tissue disorders: urticaria, pruritus Vascular disorders: hot flush Experience in Known or Suspected Cyanide Poisoning Victims Four open-label, uncontrolled, clinical studies (one of which was prospective and three of which were retrospective) were conducted in known or suspected cyanide-poisoning victims.

A total of 245 patients received hydroxocobalamin treatment in these studies. Systematic collection of adverse events was not done in all of these studies and interpretation of causality is limited due to the lack of a control group and due to circumstances of administration (e.g., use in fire victims). Adverse reactions reported in these studies listed by system organ class included: Cardiac disorders: ventricular extrasystoles Investigations: electrocardiogram repolarization abnormality, heart rate increased Respiratory, thoracic, and mediastinal disorders: pleural effusion Adverse reactions common to both the studie…

🔄 Drug Interactions 61 words

7 DRUG INTERACTIONS Formal drug interaction studies have not been conducted with CYANOKIT. Interference with Laboratory Tests Because of its deep red color, hydroxocobalamin has been found to interfere with colorimetric determination of certain laboratory parameters (e.g., clinical chemistry, hematology, coagulation, and urine parameters). Be aware of this when reporting and interpreting laboratory results [see Warnings and Precautions ( 5.5 )].

👥 Use in Specific Populations ~3 min read

8 USE IN SPECIFIC POPULATIONS Pregnancy : Based on animal studies, may cause fetal harm; however, CYANOKIT administration for cyanide poisoning may be lifesaving for the pregnant woman and fetus. Treatment should not be withheld due to pregnancy ( 8.1 ) Lactation : Breastfeeding not recommended ( 8.2 )

8.1Pregnancy Risk Summary Available data from cases reported in the published literature and postmarketing surveillance with CYANOKIT use in pregnant women are insufficient to identify a drug-associated risk for major birth defects, miscarriage, or adverse maternal and fetal outcomes. There are risks to the pregnant woman and fetus associated with untreated cyanide poisoning (see Clinical Considerations) . In animal studies, hydroxocobalamin administered to pregnant rats and rabbits during the period of organogenesis caused skeletal and soft tissue abnormalities, including alterations in the central nervous system, at exposures similar to human exposures at the therapeutic dose (see Data) .

The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively.

Clinical Considerations Disease-associated maternal and/or embryo/fetal risk Cyanide readily crosses the placenta. Cyanide poisoning is a medical emergency in pregnancy which can be fatal for the pregnant woman and fetus if left untreated. Life-sustaining therapy should not be withheld due to pregnancy.

Data Animal Data In animal studies, pregnant rats and rabbits received CYANOKIT (75, 150, or 300 mg/kg/d) during the period of organogenesis. Following intraperitoneal dosing in rats and intravenous dosing in rabbits, maternal exposures were equivalent to 0.5, 1, or 2 times the human exposure at the therapeutic dose (based on AUC). In the high dose groups for both species, maternal toxicity occurred, and there was a reduced number of live fetuses due to embryofetal resorptions.

In addition, decreased live fetal weight occurred in high dose rats, but not in rabbits. Incomplete skeletal ossification occurred in both rats and rabbits. In rats, two fetuses of the high dose group and two fetuses of the mid dose group (each from a different litter) had short, rudimentary or small front or hind legs.

Rabbit litters and fetuses exhibited a dose-dependent increase in various gross soft tissue and skeletal anomalies. The main findings in rabbits were flexed, rigid flexor or medially rotated forelimbs or hindlimbs and domed heads at external examination; enlarged anterior or posterior fontanelles of the ventricles of the brain and flat, bowed or large ribs at skeletal examination; and dilated ventricles of the brain, and thick wall of the stomach at visceral examination. It is unknown if similar findings would be observed in rats and rabbits if CYANOKIT was administered as a single dose during any critical period of development.

8.2Lactation Risk Summary Breastfeeding is not recommended during treatment with CYANOKIT. There are no data to determine when breastfeeding may be safely restarted following administration of CYANOKIT. Hydroxocobalamin and Vitamin B12 (which is formed when hydroxocobalamin combines with cyanide) are present in human milk. There are no data on the effects of hydroxocobalamin on the breastfed infant or the effects on milk production.

8.4Pediatric Use Safety and effectiveness of CYANOKIT have not been established in this population. In non-US marketing experience, a dose of 70 mg/kg has been used to treat pediatric patients.

8.5Geriatric Use Approximately 50 known or suspected cyanide poisoning victims aged 65 or older received hydroxocobalamin in clinical studies. In general, the safety and effectiveness of hydroxocobalamin in these patients was similar to that o…

🤰 Pregnancy ~2 min read

8.1Pregnancy Risk Summary Available data from cases reported in the published literature and postmarketing surveillance with CYANOKIT use in pregnant women are insufficient to identify a drug-associated risk for major birth defects, miscarriage, or adverse maternal and fetal outcomes. There are risks to the pregnant woman and fetus associated with untreated cyanide poisoning (see Clinical Considerations) . In animal studies, hydroxocobalamin administered to pregnant rats and rabbits during the period of organogenesis caused skeletal and soft tissue abnormalities, including alterations in the central nervous system, at exposures similar to human exposures at the therapeutic dose (see Data) .

The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively.

Clinical Considerations Disease-associated maternal and/or embryo/fetal risk Cyanide readily crosses the placenta. Cyanide poisoning is a medical emergency in pregnancy which can be fatal for the pregnant woman and fetus if left untreated. Life-sustaining therapy should not be withheld due to pregnancy.

Data Animal Data In animal studies, pregnant rats and rabbits received CYANOKIT (75, 150, or 300 mg/kg/d) during the period of organogenesis. Following intraperitoneal dosing in rats and intravenous dosing in rabbits, maternal exposures were equivalent to 0.5, 1, or 2 times the human exposure at the therapeutic dose (based on AUC). In the high dose groups for both species, maternal toxicity occurred, and there was a reduced number of live fetuses due to embryofetal resorptions.

In addition, decreased live fetal weight occurred in high dose rats, but not in rabbits. Incomplete skeletal ossification occurred in both rats and rabbits. In rats, two fetuses of the high dose group and two fetuses of the mid dose group (each from a different litter) had short, rudimentary or small front or hind legs.

Rabbit litters and fetuses exhibited a dose-dependent increase in various gross soft tissue and skeletal anomalies. The main findings in rabbits were flexed, rigid flexor or medially rotated forelimbs or hindlimbs and domed heads at external examination; enlarged anterior or posterior fontanelles of the ventricles of the brain and flat, bowed or large ribs at skeletal examination; and dilated ventricles of the brain, and thick wall of the stomach at visceral examination. It is unknown if similar findings would be observed in rats and rabbits if CYANOKIT was administered as a single dose during any critical period of development.

🧒 Pediatric Use 31 words

8.4Pediatric Use Safety and effectiveness of CYANOKIT have not been established in this population. In non-US marketing experience, a dose of 70 mg/kg has been used to treat pediatric patients.

🧓 Geriatric Use 47 words

8.5Geriatric Use Approximately 50 known or suspected cyanide poisoning victims aged 65 or older received hydroxocobalamin in clinical studies. In general, the safety and effectiveness of hydroxocobalamin in these patients was similar to that of younger patients. No adjustment of dose is required in elderly patients.

🆘 Overdosage 65 words

10 OVERDOSAGE No data are available about overdose with CYANOKIT in adults. Should overdose occur, treatment should be directed to the management of symptoms. Hemodialysis may be effective in such a circumstance, but is only indicated in the event of significant hydroxocobalamin-related toxicity. Because of its deep red color, hydroxocobalamin may interfere with the performance of hemodialysis machines [see Warnings and Precautions ( 5.5 )].

🧬 Clinical Pharmacology ~3 min read

12 CLINICAL PHARMACOLOGY

12.1Mechanism of Action Cyanide is an extremely toxic poison. In the absence of rapid and adequate treatment, exposure to a high dose of cyanide can result in death within minutes due to the inhibition of cytochrome oxidase resulting in arrest of cellular respiration. Specifically, cyanide binds rapidly with cytochrome a3, a component of the cytochrome c oxidase complex in mitochondria.

Inhibition of cytochrome a3 prevents the cell from using oxygen and forces anaerobic metabolism, resulting in lactate production, cellular hypoxia and metabolic acidosis. In massive acute cyanide poisoning, the mechanism of toxicity may involve other enzyme systems as well. Signs and symptoms of acute systemic cyanide poisoning may develop rapidly within minutes, depending on the route and extent of cyanide exposure.

The action of CYANOKIT in the treatment of cyanide poisoning is based on its ability to bind cyanide ions. Each hydroxocobalamin molecule can bind one cyanide ion by substituting it for the hydroxo ligand linked to the trivalent cobalt ion, to form cyanocobalamin, which is then excreted in the urine.

12.2Pharmacodynamics Administration of CYANOKIT to cyanide-poisoned patients with the attendant formation of cyanocobalamin resulted in increases in blood pressure and variable changes in heart rate upon initiation of hydroxocobalamin infusions [see Warnings and Precautions ( 5.4 )] .

12.3Pharmacokinetics Following intravenous administration of hydroxocobalamin significant binding to plasma proteins and low molecular weight physiological compounds occurs, forming various cobalamin-(III) complexes by replacing the hydroxo ligand. The low molecular weight cobalamins-(III) formed, including hydroxocobalamin, are termed “free cobalamins-(III)”; the sum of free and protein-bound cobalamins is termed “total cobalamins-(III)”. In order to reflect the exposure to the sum of all derivatives, pharmacokinetics of cobalamins-(III) (i.e., cobalamin-(III) entity without specific ligand) were investigated instead of hydroxocobalamin alone, using the concentration unit μg eq/mL.

Dose-proportional pharmacokinetics was observed following single dose intravenous administration of 2.5 to 10 g of hydroxocobalamin in healthy volunteers. Mean free and total cobalamins-(III) C max values of 113 and 579 μg eq/mL, respectively, were determined following a dose of 5 g of hydroxocobalamin. Similarly, mean free and total cobalamins-(III) C max values of 197 and 995 μg eq/mL, respectively, were determined following the dose of 10 g of hydroxocobalamin.

When normalized for body weight, male and female subjects revealed no major differences in pharmacokinetic parameters of free and total cobalamins-(III) following the administration of 5 and 10 g of hydroxocobalamin. Distribution The volume of distribution at steady state (V ss ) for both free and total cobalamins-(III) showed no apparent relationship to dose. The V ss ranged from 280.7 to 349.5 L for free cobalamins-(III), and from 21.8 to

25.6L for total cobalamins-(III). The comparatively high values for V ss of free cobalamins-(III) are due to the high protein binding of hydroxocobalamin as it reacts in the blood with plasma constituents to form cobalamins-(III) complexes and the rapid distribution of free cobalamins-(III) into tissues. Elimination The mean total amount of cobalamins-(III) excreted in urine during the collection period of 72 hours was about 60% of a 5 g dose and about 50% of a 10 g dose of hydroxocobalamin.

Overall, the total urinary excretion was calculated to be at least 60 to 70% of the administered dose. The majority of the urinary excretion occurred during the first 24 hours, but red-colored urine was observed for up to 35 days following the intravenous infusion. The mean half-life of free and total cobalamins-(III) was found to be approximately 26 to 31 hours at both the 5 g and 10 g dose level.

Metabolism Hydroxocobalamin does not undergo metabolism. Excretion…

🧬 Mechanism of Action 172 words

12.1Mechanism of Action Cyanide is an extremely toxic poison. In the absence of rapid and adequate treatment, exposure to a high dose of cyanide can result in death within minutes due to the inhibition of cytochrome oxidase resulting in arrest of cellular respiration. Specifically, cyanide binds rapidly with cytochrome a3, a component of the cytochrome c oxidase complex in mitochondria.

Inhibition of cytochrome a3 prevents the cell from using oxygen and forces anaerobic metabolism, resulting in lactate production, cellular hypoxia and metabolic acidosis. In massive acute cyanide poisoning, the mechanism of toxicity may involve other enzyme systems as well. Signs and symptoms of acute systemic cyanide poisoning may develop rapidly within minutes, depending on the route and extent of cyanide exposure.

The action of CYANOKIT in the treatment of cyanide poisoning is based on its ability to bind cyanide ions. Each hydroxocobalamin molecule can bind one cyanide ion by substituting it for the hydroxo ligand linked to the trivalent cobalt ion, to form cyanocobalamin, which is then excreted in the urine.

📦 How Supplied / Storage and Handling 150 words

16 HOW SUPPLIED/STORAGE AND HANDLING Each CYANOKIT carton (NDC 50633-310-11) consists of the following: One 250 mL glass vial, containing lyophilized hydroxocobalamin for injection, 5 g One sterile transfer spike One sterile intravenous infusion set One quick use reference guide One package insert Diluent is not included. Storage Lyophilized form Store at 25°C (77°F); excursions permitted to 15-30°C (59 to 86°F) [see USP Controlled Room Temperature]. CYANOKIT may be exposed during short periods to the temperature variations of usual transport (15 days submitted to temperatures ranging from 5 to 40°C (41 to 104°F), transport in the desert (4 days submitted to temperatures ranging from 5 to 60°C (41 to 140°F)) and freezing/defrosting cycles (15 days submitted to temperatures ranging from -20 to 40°C (-4 to 104°F)).

Reconstituted solution Store up to 6 hours at a temperature not exceeding 40ºC (104°F). Do not freeze. Discard any unused portion after 6 hours.

📦 Storage and Handling 103 words

Storage Lyophilized form Store at 25°C (77°F); excursions permitted to 15-30°C (59 to 86°F) [see USP Controlled Room Temperature]. CYANOKIT may be exposed during short periods to the temperature variations of usual transport (15 days submitted to temperatures ranging from 5 to 40°C (41 to 104°F), transport in the desert (4 days submitted to temperatures ranging from 5 to 60°C (41 to 140°F)) and freezing/defrosting cycles (15 days submitted to temperatures ranging from -20 to 40°C (-4 to 104°F)). Reconstituted solution Store up to 6 hours at a temperature not exceeding 40ºC (104°F).

Do not freeze. Discard any unused portion after 6 hours.

📋 Description ~1 min read

11 DESCRIPTION Hydroxocobalamin, the active ingredient in CYANOKIT, is cobinamide dihydroxide dihydrogen phosphate (ester), mono (inner salt), 3'-ester with 5,6-dimethyl-1-α-D-ribofuranosyl-1H-benzimidazole, an antidote. The drug substance is the hydroxylated active form of vitamin B 12 and is a large molecule in which a trivalent cobalt ion is coordinated in four positions by a tetrapyrol (or corrin) ring. It is a hygroscopic, odorless, dark red, crystalline powder that is freely soluble in water and ethanol, and practically insoluble in acetone and diethyl ether.

Hydroxocobalamin has a molecular weight of 1346.36 atomic mass units, an empirical formula of C 62 H 89 CoN 13 O 15 P and the following structural formula: CYANOKIT (hydroxocobalamin for injection) for intravenous infusion is a cyanide antidote package which contains one colorless 250 mL glass vial, containing 5 g dark red lyophilized hydroxocobalamin, pH adjusted with hydrochloric acid, one transfer spike, one intravenous administration set, one quick use reference guide and one package insert. The 5 g vial of hydroxocobalamin for injection is to be reconstituted with 200 mL of 0.9% NaCl, to give a dark red injectable solution (25 mg/mL).

If 0.9% NaCl is not readily available, 200 mL of either Lactated Ringers injection or 5% Dextrose injection (D5W) may be used as the diluent. Diluent is not included in the CYANOKIT. The pH of the reconstituted product ranges from 3.5 to 6.0. structural formula

💬 Information for Patients 214 words

17 PATIENT COUNSELING INFORMATION CYANOKIT is indicated for cyanide poisoning and in this setting, patients will likely be unresponsive or may have difficulty in comprehending counseling information. Erythema and Chromaturia Advise patients that skin redness may last up to 2 weeks and urine coloration may last for up to 5 weeks after administration of CYANOKIT. While it is not known if the skin redness predisposes to photosensitivity, patients should be advised to avoid direct sun while their skin remains discolored.

Rash Inform patients that an acneiform rash may appear anywhere from 7 to 28 days following hydroxocobalamin treatment. This rash will usually resolve without treatment within a few weeks. Renal Function Monitoring Advise patients that renal function will be monitored for 7 days following treatment with CYANOKIT or, in the event of renal impairment, until renal function returns to normal.

Pregnancy Advise pregnant women that maternal cyanide poisoning results in fetal cyanide poisoning. Treatment for cyanide poisoning may be lifesaving for both the pregnant woman and fetus. Advise females of reproductive potential to notify their provider if they were pregnant during therapy with CYANOKIT [see USE IN SPECIFIC POPULATIONS ( 8.1 )] .

Lactation Advise women that breastfeeding is not recommended during treatment with CYANOKIT [see USE IN SPECIFIC POPULATIONS ( 8.2 )] .

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗
For educational and professional reference only — not medical advice. Pricing reflects published NADAC and CMS ASP (free public data) and may differ from your acquisition cost; always verify before billing or dispensing.