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REZENOPY naloxone HCl 10 mg/.11mL Spray — NDC 83245-0003-01 package photo

REZENOPY naloxone HCl 10 mg/.11mL Spray

by Scienture LLC · 2 BLISTER PACK in 1 CARTON (83245-003-01) / 1 VIAL, SINGLE-DOSE in 1 BLISTER PACK / .11 mL in 1 VIAL, SINGLE-DOSE
NDC 83245-0003-01
🏷️ FDA NDC (as labeled) 83245-003-01 billing pads the product segment with a zero
Rx only Brand On market Non-controlled
🗂️ 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 →

This page is curated, coded, and maintained by

Compiled from public FDA, CMS, DailyMed, NADAC, and related drug data sources. Editorial policy

🆔 Identity & classification

FDA NDC (as labeled) 83245-003-01
Product NDC 83245-003
11-digit billing NDC 83245000301
RxCUI 2704891, 2704898
UNII F850569PQR
UPC 0383245003013
Application # NDA215487
SPL Set ID 5bb502aa-014f-4a36-8972-42a9439168fe
Established class (EPC) Opioid Antagonist
Mechanism of action Opioid Antagonists
DEA schedule Non-controlled
Marketing category NDA
Marketing status On market
FDA listing status Listed (active directory)
Marketing start 2026-01-29
Route NASAL
Dosage form SPRAY
Substance NALOXONE HYDROCHLORIDE
GPI-14 93400020100940
Why two NDCs? The FDA registers this code as 83245-003-01 — 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 → 83245-0003-01. 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 Opioid Antagonist class.

Pharmacologic class Opioid Antagonist
Drug family (ATC) Other opioids, Natural opium alkaloids, Benzomorphan derivatives
How it works Opioid Antagonists
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

LabelerScienture LLC
Application holderSCIENTURE LLC
FDA applicationNDA215487 (NDA)
Labeler code83245
First marketedJan 2026
Product typeHuman Prescription Drug
Portfolio2 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

📖 What it is MedlinePlus · NLM

Prescription and nonprescription (over the counter) naloxone nasal spray is used along with emergency medical treatment to reverse the life-threatening effects of a known or suspected opiate (narcotic) overdose in adults and children. Naloxone nasal spray is in a class of medications called opiate antagonists. It works by blocking the effects of opiates to relieve dangerous symptoms caused by high levels of opiates in the blood.

Read the full MedlinePlus article ↗
📗 Our plain-language guide HelloPharmacist
  • Naloxone is an emergency medicine that rapidly reverses the effects of an opioid overdose — things like very slow or stopped breathing, extreme drowsiness, or unconsciousness. You...
  • What exactly does naloxone do, and when should I use it?
  • Give one spray into one nostril. The device is ready to use — no assembly needed for most products like Narcan or Kloxxado. If the person doesn't improve within 2 to 3 minutes, giv...
  • How do I actually use the nasal spray, and what if it doesn't seem to work?
📖 Read our full Naloxone guide →

Supplement & herbal interactions

🌿 Drug–supplement interaction checker →
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 PDC6A3C0OX
    Glycerin is a clear, thick liquid derived from plant oils or fats. It acts as a humectant to retain moisture, a sweetener, and a solvent in medications.
  • 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.
  • UNII 55X04QC32I
    A strong alkaline chemical used to adjust and maintain the pH balance of liquid medicines. It helps keep the medicine stable and ensures it stays effective during storage.
  • UNII B22547B95K
    A salt derived from citric acid that helps maintain the proper acid-base balance in the medicine. It's used as a buffer to keep the product stable and at the right pH level.
  • UNII 059QF0KO0R
    Water is a liquid solvent that dissolves and mixes ingredients together in liquid medicines, syrups, and injections. It helps distribute the active drug evenly throughout the product.

5 inactive ingredients 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 DailyMed — ingredient 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.
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.

🔁 Therapeutic equivalents

ProductLabelerPackNADAC/unitTEStatusPrice vs. this
Rezenopy 10 mg/.11mLthis 83245-0003-01 Scienture 1 vial — — FDA listed —
About this product: this is the brand-name version. Some generic versions are approved by the FDA, but we could not confirm current pharmacy availability from our pricing/market data.
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

🏛️
2024
First FDA approval
Apr 2024
📍
2026
Currently FDA-listed
2 years listed
🛡️
2041
Latest patent/protection listed
not a guaranteed launch date
🔒Generic approved by FDA, but pharmacy availability is not confirmed

The FDA lists approved generic versions of this medicine, but that does not always mean a pharmacy can get one today. Patent rules, launch agreements, supply and pricing can affect when generics actually arrive.

🛡️ Latest patent/protection date listed: FDA patent/protection data lists protections through Feb 2041. This may affect when a full generic version becomes widely available, but it is not a guaranteed launch date.
📅 FDA approved Apr 19, 2024 RLD RS ⏳ ~14.4 yr to latest listed protection

Why the date isn’t exact: Generic timing can change because patents may be challenged, settled, licensed, added, removed, or worked around with a narrower label — and FDA approval does not always mean a pharmacy can get the generic today.

Patents & exclusivity — FDA Orange Book
US 12514854 — method of use (U-4397)
US 12622903 — drug product
Exclusivity NP
2024 2026 2028 2030 2032 2034 2036 2038 2040
Today
LOE
Substance patent Formulation patent Method-of-use patent Exclusivity Pediatric +6mo
🏛️FDA exclusivity
FDA-granted marketing protection. It’s separate from patents and may be shorter than patent protection.
🧪Product / substance patents
Patents covering the active ingredient, product, formulation, or related drug features.
🎯Method-of-use patents
Patents covering specific approved uses. These can sometimes be carved out with a “skinny label,” but not always.
🛈 What do these terms mean?
Patent
Legal protection listed in the Orange Book that may delay generic approval or launch. Issued by the U.S. Patent & Trademark Office.
Substance patent
Covers the active drug molecule itself — the hardest to design around. A generic generally can’t launch until it expires.
Formulation (product) patent
Covers a specific formulation or dosage form. A generic can sometimes work around it with a different formulation.
Method-of-use patent
A patent covering one specific approved use of the drug — not necessarily the whole molecule. A generic can sometimes launch with a “skinny label” that carves out the protected use and keeps the others.
Skinny label
A generic label that omits a still-patented use when the FDA allows it — letting a generic reach the market for the unprotected uses.
Exclusivity
FDA-granted marketing protection, separate from patents — e.g. 5-yr new chemical entity, 7-yr orphan drug, or a +6-month pediatric extension.
Paragraph IV
A generic applicant’s formal challenge to a listed patent. It can potentially lead to earlier generic entry, but often involves litigation or a settlement.
RLD / RS
Reference Listed Drug — the brand product the FDA uses as the reference for generic applications. Reference Standard — the product the FDA expects generics to compare against in bioequivalence testing.
TE / AB rating
FDA therapeutic-equivalence rating. An AB rating generally means the FDA considers a generic therapeutically equivalent to — and substitutable for — the brand.
LOE (loss of exclusivity)
The latest patent or exclusivity currently listed — the loss-of-exclusivity / latest-listed-protection date shown on this page. Paragraph-IV challenges and settlements can move the real date earlier; FDA approval and a manufacturer’s decision to market can move it later.

Built from the FDA Orange Book. The bars above are scaled to each protection’s expiry; the red LOE marker is the last one to lapse.

Listed patents (2)
PatentTypeUse codeExpires
US 12514854 ↗ Method of use U-4397 Feb 5, 2041
US 12622903 ↗ Drug product — Feb 5, 2041
FDA exclusivity
CodeWhat it grantsExpires
NPNew ProductApr 19, 2027
Common questions
Is there a generic version of this drug?
Yes — an FDA-approved generic equivalent is listed in the FDA Orange Book for this drug. See the alternatives section for substitutable, lower-cost products.
The FDA approved a generic — why can’t I get it at my pharmacy yet?
FDA approval and pharmacy availability are two different things. The FDA can approve a generic years before it actually reaches pharmacies, because the brand company may still hold patents or have a settlement that delays the launch. A manufacturer also has to choose to make and sell it, and have supply ready. So a drug can be “FDA-approved generic exists” and still be brand-only at the counter today.
Why do different websites show different generic release dates?
Generic availability is not based on one single date. Some sources use the first exclusivity expiration, some use the last product patent, and others use the latest method-of-use patent. Patent challenges, settlements, licenses, and label carve-outs can also change the real-world launch date. This page shows the underlying Orange Book dates so you can see why estimates may differ.
What does “FDA listed” mean?
It means the product appears in the FDA’s official NDC directory. That’s a good sign a product exists and is intended for the U.S. market, but on its own it does not confirm a pharmacy can fill it today. Where we have recent retail pricing data (NADAC) for a product, we label it “Availability likely” instead.
What does a patent or protection date mean here?
It’s the latest date currently listed in the FDA Orange Book for a patent or exclusivity on the brand product. It can affect when a full generic version becomes widely available — but it is not a guaranteed generic launch date. Generics sometimes arrive earlier (through a settlement or patent challenge) or later (a manufacturer still has to make and sell one).
What does “current Orange Book estimate” mean?
It means we are using the latest patent and exclusivity dates currently listed in the FDA Orange Book. It is not a guaranteed launch date.
Can a generic come out before the last patent expires?
Sometimes. A generic company may challenge a patent, settle with the brand manufacturer, receive a license, or obtain approval with a narrower label that avoids a patented use. In other cases, the last listed protection may delay full-label generic competition.
Can a generic come out after the listed dates?
Yes. Even after patents or exclusivity expire, a generic still needs FDA approval and a manufacturer must choose to market it. Supply, litigation, business decisions, or regulatory issues can delay actual availability.
What is the difference between patents and exclusivity?
Patents are legal protections usually issued by the U.S. Patent and Trademark Office. FDA exclusivity is marketing protection granted by the FDA. They are separate, and either one can affect generic timing.
Why are there multiple patent dates?
One drug can have several patents covering different things: the active ingredient, a formulation, a manufacturing process, or a specific approved use. That is why a page may show several expiration dates instead of one simple generic date.
Built from FDA Orange Book patent and exclusivity data. Dates are refreshed from public FDA data when available; the marker is max(latest patent expiry, latest exclusivity expiry). Paragraph-IV settlements and first-filer 180-day exclusivity can shift the real date; a method-of-use patent may allow an earlier skinny-label generic for non-protected indications. Generic launch timing is an estimate, not a guarantee.
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.

📊 Medicare Part D spend CMS · PART D · 2026 (Q1)

Medicare Part D (outpatient prescription) spending for Naloxone HCl (matched by generic name) — the program that covers self-administered drugs. 13 manufacturers.
⚠️ Drug-level data: CMS publishes Part D spending by drug, not by NDC — these figures combine every manufacturer, strength and package size sold under the name Naloxone HCl. CMS lists 4 products for this generic; we show the highest-spend one. That’s a different level of aggregation than the Medicaid card above, which is specific to this exact 11-digit NDC (pack size included), so the two aren’t directly comparable.
Period
Total Part D spend
$389.4K
Claims incl. refills
10.2K
Beneficiaries
9.2K
Spend / beneficiary
$42.54
Spend / claim
$38.07
Trend by period
💵 About the dollar figures: spending is what Part D plans paid before confidential manufacturer rebates, so the program’s real net cost is lower. A blank patient count means fewer than 11 people — CMS hides counts that small to protect privacy. Source: CMS Medicare Quarterly Part D Spending by Drug (data.cms.gov), updated quarterly.

🔬 Reported adverse events (FAERS)

Read carefully: FAERS reports are voluntary and unverified. Counts are not incidence, do not establish causation, are subject to reporting bias, and cannot be used to compare one drug to another. Shown for signal context only. Reports for REZENOPY (this brand).

Top reported reactions

Fatigue82
Nausea69
Headache50
Diarrhoea49
Pain49
Dyspnoea44
Death43

Age at onset

Child1
Adult105
Elderly94

Reporter sex

755 reports
Male · 48%
Female · 52%

Serious outcomes

Hospitalization268
Reports over time (by year) — tap or hover for the count & year
2019 2021 2023 2026 128 0
Most recent year is provisional (FAERS lags ~3 months).
Where does this data come from?
Adverse-event reports from the FDA Adverse Event Reporting System (FAERS) via openFDA. FAERS reports are voluntary and unverified — counts are not incidence and don’t establish causation.

📦 Packaging — all sizes for this product

Package NDCDescription Marketing startStatus
83245-0003-01 You're viewing this 2 BLISTER PACK in 1 CARTON (83245-003-01) / 1 VIAL, SINGLE-DOSE in 1 BLISTER PACK / .11 mL in 1 VIAL, SINGLE-DOSE 2026-01-29 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 ✓ Available
HCPCS J-code billing crosswalk — Not published for this NDC Most self-administered / retail products have no J-code — that is normal.
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 83245-003-01, 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: 83245-0003-01, written without dashes as 83245000301. 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 83245-0003-01, the first segment (83245) is the labeler code FDA assigned to Scienture LLC; the middle segment (0003) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (01) 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 Scienture LLC. Listing status can change — the directory data on this page refreshes weekly.
Who lists this product with the FDA?
Scienture LLC 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.
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 ⏱️ Dosage and Administration 💊 Dosage Forms and Strengths ⛔ Contraindications ⚠️ Warnings and Cautions 🤒 Adverse Reactions 👥 Use in Specific Populations 🤰 Pregnancy 🧒 Pediatric Use 🧓 Geriatric Use 🧬 Clinical Pharmacology 🧬 Mechanism of Action 📦 How Supplied / Storage and Handling 📋 Description 💬 Information for Patients
🎯 Indications and Usage 131 words ▾

1 INDICATIONS AND USAGE REZENOPY nasal spray is indicated for the emergency treatment of known or suspected opioid overdose, as manifested by respiratory and/or central nervous system depression in adult and pediatric patients. REZENOPY nasal spray is intended for immediate administration as emergency therapy in settings where opioids may be present. REZENOPY nasal spray is not a substitute for emergency medical care.

REZENOPY nasal spray is an opioid antagonist for the emergency treatment of known or suspected opioid overdose, as manifested by respiratory and/or central nervous system depression in adult and pediatric patients. ( 1 ) REZENOPY nasal spray is intended for immediate administration as emergency therapy in settings where opioids may be present. ( 1 ) REZENOPY nasal spray is not a substitute for emergency medical care.

( 1 )

⏱️ Dosage and Administration ~3 min read ▾

2 DOSAGE AND ADMINISTRATION REZENOPY nasal spray is for intranasal use only. ( 2.1 ) Seek emergency medical care immediately after use. ( 2.1 ) Administration of a single spray of REZENOPY nasal spray intranasally into one nostril in adult and pediatric patients.

( 2.2 ) If the patient does not respond within 2 to 3 minutes or responds and then relapses into respiratory depression, an additional dose of REZENOPY nasal spray may be given into the other nostril with a new device. ( 2.2 ) Additional supportive and/or resuscitative measures may be helpful while awaiting emergency medical assistance. ( 2.2 )

2.1Important Administration Instructions REZENOPY nasal spray is for intranasal use only. All approved naloxone hydrochloride products achieve plasma concentrations that have been shown to be efficacious in reversing the effects of opioid overdose. Comparing different products on a nominal mg-for-mg basis may be misleading [see Clinical Pharmacology (12.3) ] .

Because treatment of suspected opioid overdose must be performed by someone other than the patient, instruct the prescription recipient to inform those around them about the presence of REZENOPY nasal spray and the Instructions for Use . Instruct the patient or caregiver to read the Instructions for Use at the time they receive a prescription for REZENOPY nasal spray. Emphasize the following instructions to the patient or caregiver: Seek medical care immediately after use.

Since the duration of action of most opioids exceeds that of naloxone hydrochloride and the suspected opioid overdose may occur outside of supervised medical settings, seek immediate emergency medical assistance, keep the patient under continued surveillance until emergency personnel arrive, and administer additional doses of REZENOPY nasal spray, as necessary. Always seek emergency medical assistance in the event of a suspected, potentially life-threatening opioid emergency after administration of the first dose of REZENOPY nasal spray.

Additional doses of REZENOPY nasal spray may be required before emergency medical assistance becomes available. Do not attempt to reuse REZENOPY nasal spray. Each REZENOPY nasal spray contains a single dose of naloxone.

Re-administer REZENOPY nasal spray, using a new nasal spray, if the patient does not respond within 2 to 3 minutes or responds and then relapses into respiratory depression. Administer REZENOPY nasal spray in alternate nostrils with each dose. Administer REZENOPY nasal spray according to the printed instructions on the device label and the Instructions for Use .

Place the patient in the supine position on their back. Prior to administration, be sure the device nozzle is inserted in either nostril of the patient, support the back of the neck and tilt the patient’s head back. Do not prime or test the device prior to administration .

To administer the dose firmly press the bottom of the device plunger. Remove the device nozzle from the nostril after use. Turn patient on their side as shown in the Instructions for Use and call for emergency medical assistance immediately after administration of the first dose of REZENOPY nasal spray.

2.2Dosing in Adult and Pediatric Patients Initial Dosing The recommended initial dose of REZENOPY nasal spray in adults and pediatric patients is one spray delivered by intranasal administration. Administer REZENOPY nasal spray as quickly as possible because prolonged respiratory depression may result in damage to the central nervous system or death. Repeat Dosing Seek emergency medical assistance as soon as possible after administering the first dose of REZENOPY nasal spray.

The requirement for repeat doses of REZENOPY nasal spray depends upon the amount, type, and route of administration of the opioid being antagonized. Administer REZENOPY nasal spray in alternate nostrils with each dose. If the desired response is not obtained after 2 to 3 minutes, administer a second dose of REZENOPY nasal spray using a new REZENOPY nasal…

💊 Dosage Forms and Strengths 34 words ▾

3 DOSAGE FORMS AND STRENGTHS Nasal Spray: 10 mg of naloxone hydrochloride in 0.11 mL in a single dose nasal spray. Nasal spray: 10 mg of naloxone hydrochloride in 0.11 mL. ( 3 )

⛔ Contraindications 30 words ▾

4 CONTRAINDICATIONS REZENOPY nasal spray is contraindicated in patients known to be hypersensitive to naloxone hydrochloride or to any of the other ingredients. Hypersensitivity to naloxone hydrochloride. ( 4 )

⚠️ Warnings and Cautions ~3 min read ▾

5 WARNINGS AND PRECAUTIONS Risk of Recurrent Respiratory and CNS Depression : Due to the duration of action of naloxone relative to the opioid, keep patient under continued surveillance and administer additional doses of REZENOPY nasal spray, as necessary, using a new nasal spray device while awaiting emergency medical assistance. ( 5.1 ) Risk of Limited Efficacy with Partial Agonists or Mixed Agonists/Antagonists : Reversal of respiratory depression caused by partial agonists or mixed agonists/antagonists, such as buprenorphine and pentazocine, may be incomplete.

Larger or repeat doses may be required. ( 5.2 ) Precipitation of Severe Opioid Withdrawa l: Use in patients who are opioid dependent may precipitate opioid withdrawal. In neonates, opioid withdrawal may be life- threatening if not recognized and properly treated.

Monitor for the development of opioid withdrawal. ( 5.3 ) Risk of Cardiovascular (CV) Effects : Abrupt postoperative reversal of opioid depression may result in adverse CV effects. These events have primarily occurred in patients who had pre-existing CV disorders or received other drugs that may have similar adverse CV effects.

Monitor these patients closely in an appropriate healthcare setting after use of naloxone hydrochloride. ( 5.3 )

5.1Risk of Recurrent Respiratory and Central Nervous System Depression The duration of action of most opioids may exceed that of REZENOPY nasal spray resulting in a return of respiratory and/or central nervous system depression after an initial improvement in symptoms. Therefore, it is necessary to seek emergency medical assistance immediately after administration of the first dose of REZENOPY nasal spray and to keep the patient under continued surveillance. Administer additional doses of REZENOPY nasal spray if the patient does not adequately respond or responds and then relapses back into respiratory depression, as necessary [see Dosage and Administration (2.2) ] .

Additional supportive and/or resuscitative measures may be helpful while awaiting emergency medical assistance.

5.2Risk of Limited Efficacy with Partial Agonists or Mixed Agonist/Antagonists Reversal of respiratory depression by partial agonists or mixed agonist/antagonists such as buprenorphine and pentazocine, may be incomplete. Larger or repeat doses of naloxone hydrochloride may be required to antagonize buprenorphine because the latter has a long duration of action due to its slow rate of binding and subsequent slow dissociation from the opioid receptor [see Dosage and Administration (2.2) ]. Buprenorphine antagonism is characterized by a gradual onset of the reversal effects and a decreased duration of action of the normally prolonged respiratory depression.

5.3Precipitation of Severe Opioid Withdrawal The use of REZENOPY nasal spray in patients who are opioid dependent may precipitate opioid withdrawal characterized by the following signs and symptoms: body aches, diarrhea, tachycardia, fever, runny nose, sneezing, piloerection, sweating, yawning, nausea or vomiting, nervousness, restlessness or irritability, shivering or trembling, abdominal cramps, weakness, and increased blood pressure. In neonates, opioid withdrawal may be life-threatening if not recognized and properly treated and may include the following signs and symptoms: convulsions, excessive crying, and hyperactive reflexes.

Monitor the patient for the development of the signs and symptoms of opioid withdrawal. Abrupt postoperative reversal of opioid depression after using naloxone hydrochloride may result in nausea, vomiting, sweating, tremulousness, tachycardia, hypotension, hypertension, seizures, ventricular tachycardia and fibrillation, pulmonary edema, and cardiac arrest. Death, coma, and encephalopathy have been reported as sequelae of these events.

These events have primarily occurred in patients who had pre-existing cardiovascular disorders or received other drugs that may have similar adverse cardiovascular effects. Although a di…

🤒 Adverse Reactions ~1 min read ▾

6 ADVERSE REACTIONS The following serious adverse reactions are discussed elsewhere in the labeling: Precipitation of Severe Opioid Withdrawal [see Warnings and Precautions (5.3) ]. Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to the rates in the clinical studies of another drug and may not reflect the rates observed in practice. The following adverse reactions were observed in a REZENOPY nasal spray clinical study.

In a pharmacokinetic study of 30 healthy adult volunteers exposed to one spray of REZENOPY nasal spray, adverse reactions of abdominal pain upper, nasopharyngitis and dysgeusia were observed. The following adverse reactions have been identified primarily during post-approval use of naloxone hydrochloride in the post-operative setting. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure: Hypotension, hypertension, ventricular tachycardia and fibrillation, dyspnea, pulmonary edema, and cardiac arrest.

Death, coma, and encephalopathy have been reported as sequelae of these events. Excessive doses of naloxone hydrochloride in post-operative patients have resulted in significant reversal of analgesia, and have caused agitation. Abrupt reversal of opioid effects in persons who were physically dependent on opioids has precipitated an acute withdrawal syndrome.

Signs and symptoms have included: body aches, fever, sweating, runny nose, sneezing, piloerection, yawning, weakness, shivering or trembling, nervousness, restlessness or irritability, diarrhea, nausea or vomiting, abdominal cramps, increased blood pressure, tachycardia. In some patients, there may be aggressive behavior upon abrupt reversal of an opioid overdose. In the neonate, opioid withdrawal signs and symptoms also included convulsions, excessive crying, and hyperactive reflexes.

The following adverse reactions were observed in a REZENOPY nasal spray clinical study: abdominal pain upper, nasopharyngitis, and dysgeusia. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Scienture, LLC at 1-833-754-4917 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch

👥 Use in Specific Populations ~3 min read ▾

8 USE IN SPECIFIC POPULATIONS

8.1Pregnancy Risk Summary Life-sustaining therapy for opioid overdose should not be withheld (see Clinical Considerations). Available data from retrospective cohort studies on naloxone use in pregnant women have not identified a drug-associated risk of major birth defects, miscarriage, or other adverse maternal or fetal outcomes. In animal reproduction studies, no embryotoxic or teratogenic effects were observed in mice and rats administered naloxone hydrochloride during organogenesis at doses equivalent to 2-times and 4-times, respectively, a human dose of 20 mg/day (2 sprays of Rezenopy) (see Data) .

The 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 to 4% and 15 to 20%, respectively.

Clinical Considerations Disease-associated maternal and/or embryo/fetal risk An opioid overdose is a medical emergency and can be fatal for the pregnant woman and fetus if left untreated. Treatment with Rezenopy for opioid overdose should not be withheld because of potential concerns regarding the effects of Rezenopy on the fetus. Data Animal Data Naloxone hydrochloride was administered during organogenesis to mice and rats at doses 2-times and 4-times, respectively, a human dose of 20 mg (two REZENOPY nasal sprays) based on body surface area comparison.

These studies demonstrated no embryotoxic or teratogenic effects due to naloxone hydrochloride.

8.2Lactation Risk Summary There is no information available on the presence of naloxone in human or animal milk, the effects of the drug on the breastfed infant, or the effects of the drug on milk production. Published studies in lactating women have shown that naloxone does not effect prolactin and oxytocin hormone levels. Naloxone is minimally orally bioavailable.

8.4Pediatric Use The safety and effectiveness of Rezenopy for known or suspected opioid overdose as manifested by respiratory and/or central nervous system depression have been established in pediatric patients Use of naloxone hydrochloride in pediatric patients is supported by adult bioequivalence studies coupled with evidence from the safe and effective use of other naloxone hydrochloride drug products. No pediatric studies were conducted for REZENOPY nasal spray. Absorption of naloxone hydrochloride following intranasal administration in pediatric patients may be erratic or delayed.

Even when the opiate-intoxicated pediatric patient responds appropriately to naloxone hydrochloride, he/she must be carefully monitored for at least 24 hours, as a relapse may occur as naloxone hydrochloride is metabolized. In opioid-dependent pediatric patients, (including neonates), administration of naloxone hydrochloride may result in an abrupt and complete reversal of opioid effects, precipitating an acute opioid withdrawal syndrome. Neonatal opioid withdrawal syndrome, unlike opioid withdrawal syndrome in adults, may be life-threatening if not recognized, and should be treated according to protocols developed by neonatology experts [see Warnings and Precautions (5.3) ].

In settings such as in neonates with known or suspected exposure to maternal opioid use, where it may be preferable to avoid the abrupt precipitation of opioid withdrawal symptoms, consider use of an alternate naloxone-containing product that can be dosed according to weight and titrated to effect. Also, in situations where the primary concern is for infants at risk for opioid overdose, consider whether the availability of alternate naloxone-containing products may be better suited than REZENOPY nasal spray.

8.5Geriatric Use Geriatric patients have a greater frequency of decreased hepatic, renal, or cardiac function and of concomitant disease or other drug therapy. Therefore,…

🤰 Pregnancy ~1 min read ▾

8.1Pregnancy Risk Summary Life-sustaining therapy for opioid overdose should not be withheld (see Clinical Considerations). Available data from retrospective cohort studies on naloxone use in pregnant women have not identified a drug-associated risk of major birth defects, miscarriage, or other adverse maternal or fetal outcomes. In animal reproduction studies, no embryotoxic or teratogenic effects were observed in mice and rats administered naloxone hydrochloride during organogenesis at doses equivalent to 2-times and 4-times, respectively, a human dose of 20 mg/day (2 sprays of Rezenopy) (see Data) .

The 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 to 4% and 15 to 20%, respectively.

Clinical Considerations Disease-associated maternal and/or embryo/fetal risk An opioid overdose is a medical emergency and can be fatal for the pregnant woman and fetus if left untreated. Treatment with Rezenopy for opioid overdose should not be withheld because of potential concerns regarding the effects of Rezenopy on the fetus. Data Animal Data Naloxone hydrochloride was administered during organogenesis to mice and rats at doses 2-times and 4-times, respectively, a human dose of 20 mg (two REZENOPY nasal sprays) based on body surface area comparison.

These studies demonstrated no embryotoxic or teratogenic effects due to naloxone hydrochloride.

🧒 Pediatric Use ~1 min read ▾

8.4Pediatric Use The safety and effectiveness of Rezenopy for known or suspected opioid overdose as manifested by respiratory and/or central nervous system depression have been established in pediatric patients Use of naloxone hydrochloride in pediatric patients is supported by adult bioequivalence studies coupled with evidence from the safe and effective use of other naloxone hydrochloride drug products. No pediatric studies were conducted for REZENOPY nasal spray. Absorption of naloxone hydrochloride following intranasal administration in pediatric patients may be erratic or delayed.

Even when the opiate-intoxicated pediatric patient responds appropriately to naloxone hydrochloride, he/she must be carefully monitored for at least 24 hours, as a relapse may occur as naloxone hydrochloride is metabolized. In opioid-dependent pediatric patients, (including neonates), administration of naloxone hydrochloride may result in an abrupt and complete reversal of opioid effects, precipitating an acute opioid withdrawal syndrome. Neonatal opioid withdrawal syndrome, unlike opioid withdrawal syndrome in adults, may be life-threatening if not recognized, and should be treated according to protocols developed by neonatology experts [see Warnings and Precautions (5.3) ].

In settings such as in neonates with known or suspected exposure to maternal opioid use, where it may be preferable to avoid the abrupt precipitation of opioid withdrawal symptoms, consider use of an alternate naloxone-containing product that can be dosed according to weight and titrated to effect. Also, in situations where the primary concern is for infants at risk for opioid overdose, consider whether the availability of alternate naloxone-containing products may be better suited than REZENOPY nasal spray.

🧓 Geriatric Use 78 words ▾

8.5Geriatric Use Geriatric patients have a greater frequency of decreased hepatic, renal, or cardiac function and of concomitant disease or other drug therapy. Therefore, the systemic exposure of naloxone hydrochloride can be higher in these patients. Clinical studies of naloxone hydrochloride did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects.

Other reported clinical experience has not identified differences in responses between the elderly and younger patients.

🧬 Clinical Pharmacology ~3 min read ▾

12 CLINICAL PHARMACOLOGY

12.1Mechanism of Action Naloxone hydrochloride is an opioid antagonist that antagonizes opioid effects by competing for the same receptor sites. Naloxone hydrochloride reverses the effects of opioids, including respiratory depression, sedation, and hypotension. It can also reverse the psychotomimetic and dysphoric effects of agonist-antagonists such as pentazocine.

12.2Pharmacodynamics When naloxone hydrochloride is administered intravenously, the onset of action is generally apparent within two minutes. The time to onset of action is shorter for intravenous compared to subcutaneous or intramuscular routes of administration. The duration of action is dependent upon the dose and route of administration of naloxone hydrochloride.

12.3Pharmacokinetics In a pharmacokinetic study in 30 healthy adult subjects, the relative bioavailability (BA) of one nasal spray of a 10 mg total dose (0.11 mL of 91 mg/mL naloxone hydrochloride solution) was compared to a single dose of 0.4 mg naloxone hydrochloride intramuscular injection and a single dose of 2 mg of naloxone hydrochloride intravenous injection. For intranasal administration, the subjects were instructed not to breathe through the nose during administration of the nasal spray and remained fully supine for approximately one-hour post-dose.

For intramuscular administration, naloxone was administered as a single injection in the gluteus maximus muscle. For intravenous administration, naloxone was administered as an intravenous bolus. The pharmacokinetic parameters obtained in the study are shown in Table 1.

Table 1 Mean Pharmacokinetic Parameters (CV%) for REZENOPY nasal spray, Intramuscular and Intravenous Injections of Naloxone HCl to Healthy Subjects Parameter Rezenopy Nasal Spray 10 mg (n=29) Naloxone HCl 0.4 mg Intramuscular Injection (n=30) Naloxone HCl 2 mg Intravenous Injection (n=23) t max (h) † 0.75 (0.25, 1.03) 0.50 (0.17, 2.00) 0.08 (0.02, 0.18) C max (ng/mL) 9.11 (35.45) 0.74 (36.63) 18.41 (46.08) AUCt (h·ng/mL) 19.19 (24.81) 1.92 (19.75) 12.18 (24.30) AUC 0-∞ (h·ng/mL) 19.52 (24.78) 1.98 (19.18) 12.25 (24.22) t ½ (h) 1.33 (16.09) 1.22 (18.48) 1.18 (11.59) Dose normalized absolute BA vs.

IV †† 0.34 (30.53) 0.84 (29.06) - † t max reported as median (minimum, maximum) †† N=22 and N=23, respectively for REZENOPY nasal spray 10 mg and Naloxone HCl 0.4 mg Intramuscular Injection for Dose normalized absolute BA vs. IV Figure 1 Mean ± SD Plasma Concentration of Naloxone 0-30 minutes Following Intranasal, Intramuscular and Intravenous Administration. Figure 2 Mean ± SD Plasma Concentration of Naloxone 0-8 hours Following Intranasal, Intramuscular and Intravenous Administration.

Absorption REZENOPY nasal spray showed median Tmax 0.75 hour. The median Tmax for the 0.4 mg naloxone hydrochloride intramuscular injection was 0.5 hour. The dose normalized absolute bioavailability of one dose (10 mg) of REZENOPY nasal spray and 0.4 mg of naloxone HCl intramuscular injection compared to 2 mg of naloxone HCl intravenous injection was 34% and 84% respectively.

Distribution Following parenteral administration, naloxone is distributed in the body and readily crosses the placenta. Plasma protein binding occurs but is relatively weak. Plasma albumin is the major binding constituent, but significant binding of naloxone also occurs to plasma constituents other than albumin.

It is not known whether naloxone is excreted into human milk. Elimination Following a single intranasal administration of REZENOPY nasal spray (10 mg dose of naloxone hydrochloride), the mean plasma half-life of naloxone in healthy adults was approximately 1.33 hours (16.09% CV) hours. Following the administrations of a 0.4 mg naloxone hydrochloride intramuscular injection and a 2 mg naloxone hydrochloride intravenous injection, the half-life was 1.22 hours (18.48% CV) and 1.18 hours (11.59% CV), respectively.

In a neonatal study of naloxone hydrochloride injection, the mean (± SD) plasma half…

🧬 Mechanism of Action 48 words ▾

12.1Mechanism of Action Naloxone hydrochloride is an opioid antagonist that antagonizes opioid effects by competing for the same receptor sites. Naloxone hydrochloride reverses the effects of opioids, including respiratory depression, sedation, and hypotension. It can also reverse the psychotomimetic and dysphoric effects of agonist-antagonists such as pentazocine.

📦 How Supplied / Storage and Handling 160 words ▾

16 HOW SUPPLIED

16.1How Supplied REZENOPY nasal spray 10 mg is supplied as a carton containing two (2) blister packages (NDC 83245-003-01) each with a single spray device. REZENOPY nasal spray is not made with natural rubber latex.

16.2Storage and Handling Store REZENOPY nasal spray in the blister and cartons provided. Store between 2°C to 25°C (36°F to 77°F). Excursions permitted up to 40°C (104°F).

Do not freeze or expose to excessive heat above 40°C (104°F). Protect from light. REZENOPY nasal spray may freeze at cold temperatures.

If this happens, the device will not spray. If REZENOPY nasal spray is frozen and is needed in an emergency, do NOT wait for REZENOPY nasal spray to thaw. Get emergency medical help right away.

16.1How Supplied REZENOPY nasal spray 10 mg is supplied as a carton containing two (2) blister packages (NDC 83245-003-01) each with a single spray device. REZENOPY nasal spray is not made with natural rubber latex.

📋 Description 134 words ▾

11 DESCRIPTION Rezenopy (naloxone hydrochloride) nasal spray is a pre-filled, single dose intranasal spray. Chemically, naloxone hydrochloride is the hydrochloride salt of 17-Allyl-4,5α-epoxy- 3,14-dihydroxymorphinan-6-one hydrochloride with the following structure: Naloxone hydrochloride, an opioid antagonist, occurs as a white, to slightly off-white powder or almost white crystalline powder and contains two molecules of water of hydration. It is freely soluble in water, in dilute acids, and in strong alkali; slightly soluble in ethanol. pKa values (proton on Nitrogen) are respectively 7.94 at 20°C and 7.82 at 37°C.

Each REZENOPY nasal spray delivers 10 mg naloxone hydrochloride (equivalent to 9 mg of naloxone) in a 0.11 mL aqueous solution. Inactive ingredients include glycerin, trisodium citrate dihydrate, hydrochloric acid and sodium hydroxide to adjust pH, and purified water. The pH range is 3.9 to 4.5. chem structure

💬 Information for Patients ~2 min read ▾

17 PATIENT COUNSELING INFORMATION Advise the patient to read the FDA-approved patient labeling ( Patient Information and Instructions for Use ) . Recognition of Opioid Overdose Instruct patients and their family members or caregivers about how to recognize the signs and symptoms of an opioid overdose such as the following: Extreme somnolence - inability to awaken a patient verbally or upon a firm sternal rub. Respiratory depression - this can range from slow or shallow respiration to no respiration in a patient who is unarousable.

Other signs and symptoms that may accompany somnolence and respiratory depression include the following: Miosis Bradycardia and/or hypotension Risk of Recurrent Respiratory and Central Nervous System Depression Instruct patients and their family members or caregivers that, since the duration of action of most opioids may exceed that of REZENOPY nasal spray, they must seek immediate emergency medical assistance after the first dose of REZENOPY nasal spray and keep the patient under continued surveillance [see Dosage and Administration (2.2) , Warnings and Precautions (5.2) ].

Limited Efficacy for/with Partial Agonists or Mixed Agonist/Antagonists Instruct patients and their family members or caregivers that the reversal of respiratory depression caused by partial agonists or mixed agonist/antagonists, such as buprenorphine and pentazocine, may be incomplete and may require higher doses of naloxone hydrochloride or repeat administration of REZENOPY nasal spray, using a new nasal spray [see Dosage and Administration (2.2) , Warnings and Precautions (5.2) ]. Precipitation of Severe Opioid Withdrawal Instruct patients and their family members or caregivers that the use of REZENOPY nasal spray in patients who are opioid dependent may precipitate opioid withdrawal [see Warnings and Precautions (5.3) , Adverse Reactions (6) ].

Administration Instructions Instruct patients and their family members or caregivers to: Ensure REZENOPY nasal spray is present whenever persons may be intentionally or accidentally exposed to an opioid overdose (i.e., opioid emergencies). Administer REZENOPY nasal spray as quickly as possible if a patient is unresponsive and an opioid overdose is suspected, even when in doubt, because prolonged respiratory depression may result in damage to the central nervous system or death. REZENOPY nasal spray is not a substitute for emergency medical care [see Dosage and Administration (2.1) ].

Lay the patient on their back, tilt the patient’s head back while supporting the neck and administer REZENOPY nasal spray into one nostril. [see Dosage and Administration (2.1) ]. Use each nasal spray only one time [see Dosage and Administration (2.1) ]. Turn patient on their side as shown in the Instructions for Use and call for emergency medical assistance immediately after administration of the first dose of REZENOPY nasal spray.

Additional supportive and/or resuscitative measures may be helpful while awaiting emergency medical assistance [see Dosage and Administration (2.1) ]. Monitor the patient and administer an additional dose of REZENOPY nasal spray using a new REZENOPY nasal spray every 2 to 3 minutes, if the patient is not responding or responds and then relapses back into respiratory depression. Administer REZENOPY nasal spray in alternate nostrils with each dose [see Dosage and Administration (2.1) ].

Replace REZENOPY nasal spray before its expiration date. Manufactured for: Scienture, LLC, Commack, NY 11725 513201 Rev. 03/2026

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗
← 83244-0001-01 · Childs 83245-0053-06 · Scienture →
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.