NUEDEXTA dextromethorphan hydrobromide and quinidine sulfate 20 mg; 10 mg Capsule, Gelatin Coated, 13-count — NDC 64597-0301-13 package photo

NUEDEXTA dextromethorphan hydrobromide and quinidine sulfate 20 mg; 10 mg Capsule, Gelatin Coated, 13-count

by Avanir Pharmaceuticals, Inc. · 1 BOTTLE in 1 CARTON (64597-301-13) / 13 CAPSULE, GELATIN COATED in 1 BOTTLE
NDC 64597-0301-13
🏷️ FDA NDC (as labeled) 64597-301-13 billing pads the product segment with a zero
This package
Contains13-count Pack sizes2 compare ↓
Also priced by: Part D plans $27.38/unit — full pricing hub ↓
Also comes in: 60 capsules 64597-0301-60
Rx only Brand Discontinued Non-controlled ⚠ Discontinued by firm
🗂️ Data synced Sep 17, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →
⚠️
Excluded from the active FDA NDC Directory. The labeler reported this product as discontinued, so it is excluded from the active NDC Directory. A label may still appear on DailyMed, but the NDC is no longer in the current FDA NDC Directory. Search the FDA NDC Directory ↗

🆔 Identity & classification

FDA NDC (as labeled) 64597-301-13
Product NDC 64597-301
11-digit billing NDC 64597030113
RxCUI 1040054, 1040058
UNII 9D2RTI9KYH, J13S2394HE
Application # NDA021879
SPL Set ID 484e0918-3442-49dc-8ccf-177f1f3ee9f3
Established class (EPC) Antiarrhythmic; Cytochrome P450 2D6 Inhibitor; Sigma-1 Agonist; Uncompetitive N-methyl-D-aspartate Receptor Antagonist; Uncompetitive NMDA Receptor Antagonists
Mechanism of action Cytochrome P450 2D6 Inhibitors; Sigma-1 Receptor Agonists
DEA schedule Non-controlled
Marketing category NDA
Marketing status Discontinued
FDA listing status Discontinued by firm
Marketing start 2010-12-01
Route ORAL
Dosage form CAPSULE, GELATIN COATED
Substance DEXTROMETHORPHAN HYDROBROMIDE; QUINIDINE SULFATE
GPI-14 62609902300120
GPI class Nuedexta
GCN Seq No 066871
GCN 29290
HICL code 037278
Ingredient (HICL) Dextromethorphan Hbr/Quinidine
HIC1 code H
Therapeutic class — broad (HIC1) Nervous System (Except Autonomic)
HIC2 code H8
Therapeutic class — intermediate (HIC2) Psychoactive Drugs (Continued 2)
HIC3 code H8O
Therapeutic class — specific (HIC3) Pseudobulbar Affect (Pba) Agents, Nmda Antagonists
AHFS code 28:92.00.00
AHFS class Central Nervous System Agents, Misc.
FDB label name NUEDEXTA 20-10 MG CAPSULE
FDB brand name Nuedexta
Legend status F — Federal legend — prescription drug or device
TE code (Orange Book) AB · RLD · RS
Why two NDCs? The FDA registers this code as 64597-301-13 — 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 → 64597-0301-13. 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 Uncompetitive N-methyl-D-aspartate Receptor Antagonist class.

Pharmacologic class Uncompetitive N-methyl-D-aspartate Receptor Antagonist, Sigma-1 Agonist
Drug family (ATC) Other antidepressants, Opium alkaloids and derivatives
How it works Uncompetitive NMDA Receptor Antagonists, Sigma-1 Receptor Agonists
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

LabelerAvanir Pharmaceuticals, Inc.
Application holderOTSUKA AMERICA PHARMACEUTICAL INC
FDA applicationNDA021879 (NDA)
Labeler code64597
First marketedDec 2010
Product typeHuman Prescription Drug
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 NUEDEXTA 20-10 MG CAPSULE Ingredient Dextromethorphan Hbr/Quinidine
📖 What it is MedlinePlus · NLM

The combination of dextromethorphan and quinidine is used to treat pseudobulbar affect (PBA; a condition of sudden, frequent outbursts of crying or laughing that can not be controlled) in people with certain conditions such as amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease; condition in which the nerves that control muscle movement slowly die, causing the muscles to shrink and weaken) or multiple sclerosis (a disease in which the nerves do not function properly and patients may experience weakness, numbness, loss of muscle coordination and problems with vision, speech, and bladder co...

Read the full MedlinePlus article ↗
📗 Our plain-language guide HelloPharmacist
  • Yes — this medication is specifically approved just for pseudobulbar affect, or PBA. PBA is a condition where you laugh or cry suddenly, involuntarily, and often much more intensel...
  • What exactly is pseudobulbar affect, and is this medication just for that?
  • You'll start at one capsule a day for the first week, then move to one capsule every 12 hours after that. Some people notice an improvement within weeks of reaching the full dose,...
  • How long does it take to start working, and do I need to take it forever?
📖 Read our full Dextromethorphan and Quinidine guide →
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.

💊 What it looks like

Color Red
ShapeCapsule
ImprintDMQ;20;10
Size19 mm
ScoringNot scored
One label can cover several strengths, so colors may be combined — always confirm a loose pill against the dispensed prescription label or a pharmacist.
Where does this data come from?
Physical description (imprint, shape, color, scoring, coating) from this product’s FDA Structured Product Labeling (SPL), mirrored from DailyMed / openFDA.

🧪 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 M28OL1HH48
    Croscarmellose sodium is a plant-based substance derived from cellulose. It acts as a disintegrant, helping tablets and capsules break down quickly in the digestive system so the medicine can be absorbed.
  • UNII EWQ57Q8I5X
    Lactose monohydrate is a natural sugar derived from milk. It serves as a filler and binder in tablets and capsules, helping create the proper size, texture, and consistency of the medicine.
  • UNII 70097M6I30
    Magnesium stearate is a salt made from magnesium and stearic acid, a fatty substance. It's used in tablets and capsules as a lubricant and glidant to help ingredients flow smoothly during manufacturing and prevent sticking.
  • UNII OP1R32D61U
    Microcrystalline cellulose is a purified form of cellulose, a natural fiber from plant sources. It acts as a binder and filler in tablets and capsules, helping hold ingredients together and give the medicine its shape and size.
  • UNII ETJ7Z6XBU4
    Silicon dioxide is a naturally occurring mineral used as a glidant and anti-caking agent. It helps powder ingredients flow smoothly and prevents clumping during manufacturing and storage.

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 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 eachPer 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 · Q2 2026 $27.38 $355.96 / 13 capsules
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
Nuedexta 20 mg/1; 10 mg 59148-0053-16 Otsuka 60 capsules $26.600 AB Availability likely
Dextromethorphan hydrobromide and quinidine sulfate 20 mg/1; 10 mg 31722-0693-60 Camber 60 capsules AB FDA listed
Nuedexta 20 mg/1; 10 mgthis 64597-0301-13 Avanir 13 capsules AB Discontinued
Dextromethorphan hydrobromide and quinidine sulfate 20 mg/1; 10 mg 00480-2602-06 Teva 60 capsules AB 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

🏛️
2010
First FDA approval
Oct 2010
📍
2026
Currently FDA-listed
16 years listed
🔓
·
Listed protection lapsed
listed protections lapsed 2026
🔒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: The latest listed FDA patent/protection lapsed Aug 2026 — those protections no longer apply, though a generic still needs FDA approval and a manufacturer to market it.
📅 FDA approved Oct 29, 2010 AB TE-rated RLD RS

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 7659282 — method of use (U-1093)
2010 2012 2014 2016 2018 2020 2022 2024 2026
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 (1)
PatentTypeUse codeExpires
US 7659282 ↗ Method of use U-1093 Aug 13, 2026
Common questions
Is there a generic version of NUEDEXTA 20-10 MG CAPSULE?
Yes — an FDA-approved generic equivalent is listed in the FDA Orange Book for NUEDEXTA 20-10 MG CAPSULE. 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.

💊 Medicaid utilization by pack size

Medicaid (SDUD) totals over the four most recent reported quarters for every package size of this drug — handy when a specific package (e.g. a starter/titration pack) carries little or no Medicaid volume on its own.
60 capsules64597-0301-60 424 Rx · $575,263
Drug total (last 4 qtrs): 424 Rx · 22,232 units · $575,263 gross reimbursed
Tap a pack size to open its page. Source: CMS State Drug Utilization Data, last 4 quarters.

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

Medicare Part D (outpatient prescription) spending for Nuedexta — the program that covers self-administered drugs. 2 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 Nuedexta. 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
$36.39M
Claims incl. refills
31.2K
Beneficiaries
9.5K
Spend / beneficiary
$3,847.88
Spend / claim
$1,164.83
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 NUEDEXTA (this brand).

Top reported reactions

Fall207
Death191
Dizziness169
Therapy Interrupted161
Fatigue144
Diarrhoea135
Nausea110

Age at onset

Child3
Adolescent2
Adult152
Elderly114

Reporter sex

0 reports
Male · 34%
Female · 66%
Unknown · 0%

Serious outcomes

Death278
Reports over time (by year) — tap or hover for the count & year
2019 2021 2023 2026 331 34
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 Per unit Per pack Marketing startStatus
64597-0301-13 You're viewing this 1 BOTTLE in 1 CARTON (64597-301-13) / 13 CAPSULE, GELATIN COATED in 1 BOTTLE 2010-12-01 Discontinued by firm
64597-0301-60 60 CAPSULE, GELATIN COATED in 1 BOTTLE (64597-301-60) $26.60 / ea $1,595.97 2010-12-01 Discontinued by firm

This pack shows little to no recent Medicaid volume — the 60 capsules pack carries most fills. See all packs ↓

Pack size FAQ

What quantity is in NDC 64597-0301-13?
NDC 64597-0301-13 is a 13-count package — 1 bottle in 1 carton / 13 capsule, gelatin coated in 1 bottle.
What is the difference between NDC 64597-0301-13 and NDC 64597-0301-60?
Both are NUEDEXTA dextromethorphan hydrobromide and quinidine sulfate 20 mg; 10 mg Capsule, Gelatin Coated — the drug itself is identical. NDC 64597-0301-13 is the 13-count package, while NDC 64597-0301-60 is the 60 capsules package.
What NDC number is used to bill for this package of NUEDEXTA dextromethorphan hydrobromide and quinidine sulfate 20 mg; 10 mg Capsule, Gelatin Coated?
Bill NDC 64597-0301-13 — the 11-digit billing format is 64597030113. Pharmacy and medical claims use the 11-digit form; the FDA label may print a shorter form of the same code.

Prices are the latest CMS NADAC pharmacy acquisition cost per NDC; per-pack figures are per-unit × pack quantity, shown only when the pack is denominated in the same measure NADAC prices.

🧭 About this NDC listing & data coverage

Finished prescription product No longer marketed (per FDA listing data)
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.
What does the discontinued status mean for this NDC?
The labeler reported a marketing end date (or the listing was delisted), so this specific package is no longer actively marketed. Remaining stock may still be dispensed for a time, and the NDC stays valid for historical records and claims — but data feeds (pricing, labeling) typically stop updating for it. Other package sizes or other manufacturers' versions of the same medication may still be marketed — see the equivalents section where available.
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 64597-301-13, 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: 64597-0301-13, written without dashes as 64597030113. 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 64597-0301-13, the first segment (64597) is the labeler code FDA assigned to Avanir Pharmaceuticals, Inc.; the middle segment (0301) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (13) identifies this exact package size and type. Together they name one specific package of one specific product.
Does this product come in other package sizes?
Yes — the FDA directory lists 1 other package presentation of this same product, including 60 capsules (64597-0301-60). Each has its own NDC and its own page — see the package list near the top of this page.
Who lists this product with the FDA?
Avanir Pharmaceuticals, 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.
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 108 words

1 INDICATIONS AND USAGE NUEDEXTA is indicated for the treatment of pseudobulbar affect (PBA). PBA occurs secondary to a variety of otherwise unrelated neurologic conditions, and is characterized by involuntary, sudden, and frequent episodes of laughing and/or crying. PBA episodes typically occur out of proportion or incongruent to the underlying emotional state.

PBA is a specific condition, distinct from other types of emotional lability that may occur in patients with neurological disease or injury. NUEDEXTA is a combination product containing dextromethorphan hydrobromide (an uncompetitive NMDA receptor antagonist and sigma-1 agonist) and quinidine sulfate (a CYP450 2D6 inhibitor) indicated for the treatment of pseudobulbar affect (PBA). ( 1 )

⏱️ Dosage and Administration 97 words

2 DOSAGE AND ADMINISTRATION Starting dose: one capsule daily by mouth for 7 days. ( 2.1 ) Maintenance dose: After 7 days, 1 capsule every 12 hours. ( 2.1 )

2.1Recommended Dose The recommended starting dose of NUEDEXTA is one capsule daily by mouth for the initial seven days of therapy. On the eighth day of therapy and thereafter, the daily dose should be a total of two capsules a day, given as one capsule every 12 hours. The need for continued treatment should be reassessed periodically, as spontaneous improvement of PBA occurs in some patients.

💊 Dosage Forms and Strengths 44 words

3 DOSAGE FORMS AND STRENGTHS NUEDEXTA capsules contain 20 mg dextromethorphan hydrobromide and 10 mg quinidine sulfate in a brick red gelatin capsule with “DMQ 20-10” printed in white ink on the capsule. Capsules: Dextromethorphan hydrobromide 20 mg/quinidine sulfate 10 mg. ( 3 )

Contraindications ~2 min read

4 CONTRAINDICATIONS Concomitant use with quinidine, quinine, or mefloquine. ( 4.1 ) Patients with a history of quinidine, quinine or mefloquine-induced thrombocytopenia, hepatitis, or other hypersensitivity reactions. ( 4.2 ) Patients with known hypersensitivity to dextromethorphan.

( 4.2 ) Use with an MAOI or within 14 days of stopping an MAOI. Allow 14 days after stopping NUEDEXTA before starting an MAOI. ( 4.3 ) Prolonged QT interval, congenital long QT syndrome, history suggestive of torsades de pointes, or heart failure.

( 4.4 ) Complete atrioventricular (AV) block without implanted pacemaker, or patients at high risk of complete AV block. ( 4.4 ) Concomitant use with drugs that both prolong QT interval and are metabolized by CYP2D6 (e.g., thioridazine or pimozide). ( 4.4 )

4.1Quinidine and Related D rugs NUEDEXTA contains quinidine, and should not be used concomitantly with other drugs containing quinidine, quinine, or mefloquine.

4.2Hypersensitivity NUEDEXTA is contraindicated in patients with a history of NUEDEXTA, quinine, mefloquine or quinidine-induced thrombocytopenia, hepatitis, bone marrow depression or lupus-like syndrome. NUEDEXTA is also contraindicated in patients with a known hypersensitivity to dextromethorphan (e.g. rash, hives) [ see Warnings and Precautions ( 5.1 ) ] .

4.3MAOIs NUEDEXTA is contraindicated in patients taking monoamine oxidase inhibitors (MAOIs) or in patients who have taken MAOIs within the preceding 14 days, due to the risk of serious and possibly fatal drug interactions, including serotonin syndrome. Allow at least 14 days after stopping NUEDEXTA before starting an MAOI [ see Drug Interactions ( 7.1 ) ] .

4.4Cardiovascular NUEDEXTA is contraindicated in patients with a prolonged QT interval, congenital long QT syndrome or a history suggestive of torsades de pointes, and in patients with heart failure [ see Warnings and Precautions ( 5.3 ) ] . NUEDEXTA is contraindicated in patients receiving drugs that both prolong QT interval and are metabolized by CYP2D6 (e.g., thioridazine and pimozide), as effects on QT interval may be increased [ see Drug Interactions ( 7.2 ) ] . NUEDEXTA is contraindicated in patients with complete atrioventricular (AV) block without implanted pacemakers, or in patients who are at high risk of complete AV block.

⚠️ Warnings and Cautions ~2 min read

5 WARNINGS AND PRECAUTIONS Thrombocytopenia or other hypersensitivity reactions: Discontinue if occurs. ( 5.1 ) Hepatitis: Discontinue if occurs. ( 5.2 ) QT Prolongation: Monitor ECG if concomitant use of drugs that prolong QT interval cannot be avoided or if concomitant CYP3A4 inhibitors used.

( 5.3 ) Left ventricular hypertrophy (LVH) or left ventricular dysfunction (LVD): Monitor ECG in patients with LVH or LVD. ( 5.3 ) CYP2D6 substrate: Nuedexta inhibits CYP2D6. Accumulation of parent drug and/or failure of metabolite formation may decrease safety and/or efficacy of concomitant CYP2D6 metabolized drugs.

Adjust dose of CYP2D6 substrate or use alternative treatment when clinically indicated. ( 5.4 , 12.4 ) Dizziness: Take precautions to reduce falls. ( 5.5 ) Serotonin syndrome: Use of NUEDEXTA with selective serotonin reuptake inhibitor (SSRIs) or tricyclic antidepressants increases the risk.

Discontinue if occurs. ( 5.6 , 7.4 ) Anticholinergic effects of quinidine: Monitor for worsening in myasthenia gravis and other sensitive conditions. ( 5.7 )

5.1Thrombocytopenia and Other Hypersensitivity Reactions Quinidine can cause immune-mediated thrombocytopenia that can be severe or fatal. Non-specific symptoms, such as lightheadedness, chills, fever, nausea, and vomiting, can precede or occur with thrombocytopenia. NUEDEXTA should be discontinued immediately if thrombocytopenia occurs, unless the thrombocytopenia is clearly not drug-related, as continued use increases the risk for fatal hemorrhage.

Likewise, NUEDEXTA should not be restarted in sensitized patients, because more rapid and more severe thrombocytopenia than the original episode can occur. NUEDEXTA should not be used if immune-mediated thrombocytopenia from structurally related drugs, including quinine and mefloquine is suspected, as cross-sensitivity can occur. Quinidine-associated thrombocytopenia usually, but not always, resolves within a few days of discontinuation of the sensitizing drug.

Quinidine has also been associated with a lupus-like syndrome involving polyarthritis, sometimes with a positive antinuclear antibody test. Other associations include rash, bronchospasm, lymphadenopathy, hemolytic anemia, vasculitis, uveitis, angioedema, agranulocytosis, the sicca syndrome, myalgia, elevation in serum levels of skeletal-muscle enzymes, and pneumonitis.

5.2Hepatotoxicity Hepatitis, including granulomatous hepatitis, has been reported in patients receiving quinidine, generally during the first few weeks of therapy. Fever may be a presenting symptom, and thrombocytopenia or other signs of hypersensitivity may also occur. Most cases remit when quinidine is withdrawn.

5.3Cardiac Effects NUEDEXTA causes dose-dependent QTc prolongation [ see Clinical Pharmacology ( 12.2 ) ] . QT prolongation can cause torsades de pointes-type ventricular tachycardia, with the risk increasing as the degree of prolongation increases. When initiating NUEDEXTA in patients at risk of QT prolongation and torsades de pointes, electrocardiographic (ECG) evaluation of QT interval should be conducted at baseline and 3-4 hours after the first dose.

This includes patients concomitantly taking/initiating drugs that prolong the QT interval or that are strong or moderate CYP3A4 inhibitors, and patients with left ventricular hypertrophy (LVH) or left ventricular dysfunction (LVD). LVH and LVD are more likely to be present in patients with chronic hypertension, known coronary artery disease, or history of stroke. LVH and LVD can be diagnosed utilizing echocardiography or another suitable cardiac imaging modality.

Strong and moderate CYP3A inhibitors include, but are not limited to, atazanavir, clarithromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, amprenavir, aprepitant, diltiazem, erythromycin, fluconazole, fosamprenavir, grapefruit juice, and verapamil. Reevaluate ECG if risk factors for arrhythmia change during the course of treatment…

🤒 Adverse Reactions ~3 min read

6 ADVERSE REACTIONS A total of 946 patients participated in four Phase 3 controlled and uncontrolled PBA studies and received at least one dose of the combination product of dextromethorphan/quinidine in various strengths at the recommended or higher than the recommended dose. Of those patients, 393 patients were exposed for at least 180 days and 294 patients were exposed for at least one year. Median exposure was 168 days.

Controlled trials enrolled only patients with either ALS or MS. Uncontrolled studies enrolled 136 patients with PBA secondary to a wide variety of underlying neurological conditions including stroke (45 patients) and traumatic brain injury (23 patients). Consequently, patients with other underlying neurologic diseases may experience other adverse reactions not described below.

The most common adverse reactions (incidence of ≥ 3% and two-fold greater than placebo) in patients taking NUEDEXTA are diarrhea, dizziness, cough, vomiting, asthenia, peripheral edema, urinary tract infection, influenza, increased gamma-glutamyltransferase, and flatulence. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Avanir Pharmaceuticals, Inc. at 1-855-4NUEDEX (468-3339) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1Clinical Trials Experience A 12-week, placebo-controlled study evaluated NUEDEXTA (dextromethorphan 20 mg/quinidine 10 mg) (N=107) and a 30 mg dextromethorphan/10 mg quinidine combination (N=110) compared to placebo (N=109). Approximately 60% of patients had ALS and 40% had MS. Patients were 25 to 80 years of age, with a mean age of approximately 51 years.

Three (3) ALS patients in each drug treatment arm and 1 ALS patient in the placebo arm died during the 12-week placebo-control period. All deaths were consistent with the natural progression of ALS. Adverse Reactions Leading to Discontinuation The most commonly reported adverse reactions (incidence ≥ 2% and greater than placebo) that led to discontinuation with the 20 mg dextromethorphan/10 mg quinidine twice daily dose were muscle spasticity (3%), respiratory failure (1%), abdominal pain (2%), asthenia (2%), dizziness (2%), fall (1%), and muscle spasms (2%).

Most Common Adverse Reactions Adverse drug reactions that occurred in ≥ 3% of patients receiving the 20 mg dextromethorphan/10 mg quinidine twice daily dose, and at an incidence of ≥ 2 times placebo in short-term clinical trials in ALS and MS are provided in Table 1. Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to the rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.

Table 1: Adverse Drug Reactions with an Incidence of ≥ 3% of Patients and ≥ 2x Placebo in NUEDEXTA-treated Patients by System-Organ Class and Preferred Term NUEDEXTA N=107 % Placebo N=109 % Diarrhea 13 6 Dizziness 10 5 Cough 5 2 Vomiting 5 1 Asthenia 5 2 Peripheral edema 5 1 Urinary tract infection 4 1 Influenza 4 1 Increased gamma- glutamyltransferase 3 0 Flatulence 3 1

6.2Long-Term Exposure with NUEDEXTA The experience in open-label clinical trials is consistent with the safety profile observed in the placebo-controlled clinical trials.

6.3Safety Experience of Individual Components The following adverse reactions have been reported with the use of the individual components of NUEDEXTA, dextromethorphan and quinidine, from post-marketing experience. Because these reactions are reported voluntarily from a population of unknown size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Dextromethorphan Drowsiness, dizziness, nervousness or restlessness, nausea, vomiting, and stomach pain.

Quinidine Cinchonism is most often a sign of chronic quinidine toxicity, but it may appear in sensitive patients after a single moderate dose of several hundred milligrams. Cinchonism is characterized by nausea, v…

🔄 Drug Interactions ~3 min read

7 DRUG INTERACTIONS Desipramine: Exposure increases 8-fold. Reduce desipramine dose and adjust based on clinical response. ( 7.5 , 12.4 ) Paroxetine: Exposure increases 2-fold. Reduce paroxetine dose and adjust based on clinical response. ( 7.5 , 12.4 ) Digoxin: Increased digoxin substrate plasma concentration may occur. ( 7.6 )

7.1MAOIs Do not use NUEDEXTA with monoamine oxidase inhibitors (MAOIs) or in patients who have taken MAOIs within the preceding 14 days [ see Contraindications ( 4.3 ) ] .

7.2Drugs that Prolong QT and are Metabolized by CYP2D6 Do not use with drugs that both prolong QT interval and are metabolized by CYP2D6 (e.g., thioridazine or pimozide) [ see Contraindications ( 4.4 ) ] .

7.3Drugs that Prolong QT and Concomitant CYP3A4 Inhibitors Recommend ECG in patients taking drugs with NUEDEXTA that prolong the QT interval and in patients taking concomitant moderate or strong CYP3A4 inhibitors [ see Warnings and Precautions ( 5.3 ) ] .

7.4SSRIs and Tricyclic Antidepressants Use of NUEDEXTA with SSRIs or tricyclic antidepressants increases the risk of ‘serotonin syndrome’ [ see Warnings and Precautions ( 5.6 ) ] .

7.5CYP2D6 Substrate The co-administration of NUEDEXTA with drugs that undergo extensive CYP2D6 metabolism may result in altered drug effects, due to accumulation of parent drug and/or failure of metabolite formation [ see Warnings and Precautions ( 5.4 ) ] . Therapy with medications that are primarily metabolized by CYP2D6 and that have a relatively narrow therapeutic index should be initiated at a low dose if a patient is receiving NUEDEXTA concurrently. If NUEDEXTA is added to the treatment regimen of a patient already receiving a drug primarily metabolized by CYP2D6, the need for a dose modification of the original medication should be considered.

The extent to which CYP2D6 interactions may pose clinical problems will depend on the pharmacokinetics of the substrate involved. In cases of prodrugs whose actions are mediated by the CYP2D6-produced metabolites (for example, codeine and hydrocodone, whose analgesic and antitussive effects appear to be mediated by morphine and hydromorphone, respectively), it may not be possible to achieve the desired clinical benefits in the presence of NUEDEXTA due to quinidine-mediated inhibition of CYP2D6. Consider use of alternative treatment with NUEDEXTA when clinically indicated.

Drug interactions with desipramine and paroxetine have been studied in controlled clinical trials with a higher dose combination of dextromethorphan/quinidine (dextromethorphan 30 mg/quinidine 30 mg) than NUEDEXTA; study results are described below. No other drug interactions with CYP2D6 substrates have been systematically investigated, although concomitant use of such drugs was allowed in clinical trials with NUEDEXTA and in clinical trials with higher dose formulations of dextromethorphan/quinidine. Desipramine (CYP2D6 substrate): The tricyclic antidepressant desipramine is metabolized primarily by CYP2D6.

A drug interaction study was conducted between a higher combination dose of dextromethorphan (dextromethorphan 30 mg/quinidine 30 mg) and desipramine 25 mg. The combination dose of dextromethorphan/quinidine increased steady state desipramine levels approximately 8-fold. If NUEDEXTA and desipramine are prescribed concomitantly, the initial dose of desipramine should be markedly reduced.

The dose of desipramine can then be adjusted based on clinical response; however, a dose above 40 mg/day is not recommended. Paroxetine (CYP2D6 inhibitor and substrate) : When the combination dose of dextromethorphan 30 mg/quinidine 30 mg was added to paroxetine at steady state, paroxetine exposure (AUC 0-24 ) increased by 1.7 fold and C max increased by 1.5 fold. Consideration should be given to initiating treatment with a lower dose of paroxetine if given with NUEDEXTA.

The dose of paroxetine can then be adjusted based on clinical response; however, dosage above 35 mg/day is not recommended. 7.6…

👥 Use in Specific Populations ~3 min read

8 USE IN SPECIFIC POPULATIONS Pregnancy: Based on animal data, may cause fetal harm. ( 8.1 )

8.1Pregnancy Risk Summary There are no adequate data on the developmental risk associated with the use of NUEDEXTA in pregnant women. In oral studies conducted in rats and rabbits, a combination of dextromethorphan/quinidine demonstrated developmental toxicity, including teratogenicity (rabbits) and embryolethality, when given to pregnant animals (see Data) . 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.

The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. Data Animal Data When dextromethorphan/quinidine was administered orally (0/0, 5/100, 15/100, and 50/100 mg/kg/day) to pregnant rats during the period of organogenesis, embryo-fetal deaths were observed at the highest dose tested and reduced skeletal ossification was observed at all doses. The lowest dose tested (5/100 mg/kg/day) is approximately 1/50 times the recommended human dose (RHD) of 40/20 mg/day on a mg/m 2 basis.

Oral administration to pregnant rabbits during organogenesis in two separate studies (0/0, 5/60, 15/60, and 30/60 mg/kg/day; 0/0, 5/100, 15/100, and 50/100 mg/kg/day) resulted in an increased incidence of fetal malformations at all but the lowest dose tested. The no-effect dose (5/100 mg/kg/day) is approximately 2/100 times the RHD on a mg/m 2 basis. When dextromethorphan/quinidine was orally administered to female rats during pregnancy and lactation in two separate studies (0/0, 5/100, 15/100, and 30/100 mg/kg/day; 0/0, 5/100, 15/100, and 50/100 mg/kg/day), pup survival and pup weight were decreased at all doses, and developmental delay was observed in offspring at the mid and high doses.

A no-effect dose for adverse developmental effects was not identified. The lowest dose tested (5/100 mg/kg/day) is approximately 1/50 times the RHD on a mg/m 2 basis. When dextromethorphan/quinidine was orally administered (0/0, 5/50, 15/50, 25/50 mg/kg) to male and female rats on postnatal day (PND) 7, the highest dose resulted in neuronal death in brain (thalamus and medulla oblongata).

PND 7 in rat corresponds to the third trimester of the gestation through the first several months of life but may extend to approximately three years of age in humans.

8.2Lactation Risk Summary Quinidine is excreted in human milk. It is not known whether dextromethorphan is excreted in human milk. There are no data on the effects of quinidine or dextromethorphan on the breastfed infant or the effects on milk production.

The development and health benefits of breastfeeding should be considered along with the mother’s clinical need for NUEDEXTA and any potential adverse effects on the breastfed infant from NUEDEXTA or from the underlying material condition.

8.4Pediatric Use The safety and effectiveness in pediatric patients below the age of 18 have not been established.

8.5Geriatric Use Of the total number of patients with PBA in clinical studies of NUEDEXTA, 14 percent were 65 years old and over, while 2 percent were 75 and over. Clinical studies of NUEDEXTA did not include sufficient number of patients aged 65 and over to determine whether they respond differently than younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

8.6Renal Impairment Dose adjustment of NUEDEXTA is not required in patients with mild to moderate renal impairment [ see Clinical Pharmacology ( 12.3 )] . The pharmacokinetics of NUEDEXTA have not been evaluated in patients with severe renal impairment; however, increases in dextromethorphan and/or quinidine levels are likely to be observed.

8.7 Hepatic Impairment Dose adjustm…

🤰 Pregnancy ~2 min read

8.1Pregnancy Risk Summary There are no adequate data on the developmental risk associated with the use of NUEDEXTA in pregnant women. In oral studies conducted in rats and rabbits, a combination of dextromethorphan/quinidine demonstrated developmental toxicity, including teratogenicity (rabbits) and embryolethality, when given to pregnant animals (see Data) . 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.

The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. Data Animal Data When dextromethorphan/quinidine was administered orally (0/0, 5/100, 15/100, and 50/100 mg/kg/day) to pregnant rats during the period of organogenesis, embryo-fetal deaths were observed at the highest dose tested and reduced skeletal ossification was observed at all doses. The lowest dose tested (5/100 mg/kg/day) is approximately 1/50 times the recommended human dose (RHD) of 40/20 mg/day on a mg/m 2 basis.

Oral administration to pregnant rabbits during organogenesis in two separate studies (0/0, 5/60, 15/60, and 30/60 mg/kg/day; 0/0, 5/100, 15/100, and 50/100 mg/kg/day) resulted in an increased incidence of fetal malformations at all but the lowest dose tested. The no-effect dose (5/100 mg/kg/day) is approximately 2/100 times the RHD on a mg/m 2 basis. When dextromethorphan/quinidine was orally administered to female rats during pregnancy and lactation in two separate studies (0/0, 5/100, 15/100, and 30/100 mg/kg/day; 0/0, 5/100, 15/100, and 50/100 mg/kg/day), pup survival and pup weight were decreased at all doses, and developmental delay was observed in offspring at the mid and high doses.

A no-effect dose for adverse developmental effects was not identified. The lowest dose tested (5/100 mg/kg/day) is approximately 1/50 times the RHD on a mg/m 2 basis. When dextromethorphan/quinidine was orally administered (0/0, 5/50, 15/50, 25/50 mg/kg) to male and female rats on postnatal day (PND) 7, the highest dose resulted in neuronal death in brain (thalamus and medulla oblongata).

PND 7 in rat corresponds to the third trimester of the gestation through the first several months of life but may extend to approximately three years of age in humans.

🧒 Pediatric Use 19 words

8.4Pediatric Use The safety and effectiveness in pediatric patients below the age of 18 have not been established.

🧓 Geriatric Use 95 words

8.5Geriatric Use Of the total number of patients with PBA in clinical studies of NUEDEXTA, 14 percent were 65 years old and over, while 2 percent were 75 and over. Clinical studies of NUEDEXTA did not include sufficient number of patients aged 65 and over to determine whether they respond differently than younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

🆘 Overdosage ~2 min read

10 OVERDOSAGE Evaluation and treatment of NUEDEXTA overdose is based on experience with the individual components, dextromethorphan and quinidine. Metabolism of the dextromethorphan component of NUEDEXTA is inhibited by the quinidine component, such that adverse effects of overdose due to NUEDEXTA might be more severe or more persistent compared to overdose of dextromethorphan alone. During development of NUEDEXTA, dose combinations of dextromethorphan/quinidine containing up to 6-times higher dextromethorphan dose and 12-times higher quinidine dose were studied.

The most common adverse events were mild to moderate nausea, dizziness, and headache. The most important adverse effects of acute quinidine overdose are ventricular arrhythmias and hypotension. Other signs and symptoms of overdose may include vomiting, diarrhea, tinnitus, high-frequency hearing loss, vertigo, blurred vision, diplopia, photophobia, headache, confusion, and delirium.

While therapeutic doses of quinidine for treatment of cardiac arrhythmia or malaria are generally 10-fold, or more, higher than the dose of quinidine in NUEDEXTA, potentially fatal cardiac arrhythmia, including torsades de pointes, can occur at quinidine exposures that are possible from NUEDEXTA overdose. Adverse effects of dextromethorphan overdose include nausea, vomiting, stupor, coma, respiratory depression, seizures, tachycardia, hyperexcitability, and toxic psychosis. Other adverse effects include ataxia, nystagmus, dystonia, blurred vision, and changes in muscle reflexes.

Dextromethorphan may cause serotonin syndrome, and this risk is increased by overdose, particularly if taken with other serotonergic agents, SSRIs or tricyclic antidepressants.

10.1Treatment of Overdose While serum quinidine levels can be measured, electrocardiographic monitoring of the QTc interval is a better predictor of quinidine-induced arrhythmia. Treatment of hemodynamically unstable polymorphic ventricular tachycardia (including torsades de pointes) is either immediate cardioversion or, if a cardiac pacemaker is in place or immediately available, immediate overdrive pacing. After pacing or cardioversion, further management must be guided by the length of the QTc interval.

Factors contributing to QTc prolongation (especially hypokalemia and hypomagnesemia) should be sought out and (if possible) aggressively corrected. Prevention of recurrent torsades de pointes may require sustained overdrive pacing or the cautious administration of isoproterenol (30-150 ng/kg/min). Because of the theoretical possibility of QT-prolonging effects that might be additive to those of quinidine, other antiarrhythmics with Class I (procainamide) or Class III activities should (if possible) be avoided.

If the post-cardioversion QTc interval is prolonged, then the pre-cardioversion polymorphic ventricular tachyarrhythmia was (by definition) torsades de pointes. In this case, class Ib antiarrhythmics like lidocaine are unlikely to be of value, and other Class I and Class III antiarrhythmics are likely to exacerbate the situation. Quinidine-induced hypotension that is not due to an arrhythmia is likely to be a consequence of quinidine-related α-blockade and vasorelaxation.

Treatment of hypotension should be directed at symptomatic and supportive measures. Repletion of central volume (Trendelenburg positioning, saline infusion) may be sufficient therapy; other interventions reported to have been beneficial in this setting are those that increase peripheral vascular resistance, including α-agonist catecholamines (norepinephrine). Quinidine : Adequate studies of orally administered activated charcoal in human overdoses of quinidine have not been reported, but there are animal data showing significant enhancement of systemic elimination following this intervention, and there is at least one human case report in which the elimination half-life of quinidine in the serum was apparently shortened by repeated gastric lavage.

Activated charcoal…

🧬 Clinical Pharmacology ~3 min read

12 CLINICAL PHARMACOLOGY

12.1Mechanism of Action Dextromethorphan (DM) is a sigma-1 receptor agonist and an uncompetitive NMDA receptor antagonist. Quinidine increases plasma levels of dextromethorphan by competitively inhibiting cytochrome P450 2D6, which catalyzes a major biotransformation pathway for dextromethorphan. The mechanism by which dextromethorphan exerts therapeutic effects in patients with pseudobulbar affect is unknown.

12.2Pharmacodynamics Cardiac Electrophysiology The effect of dextromethorphan 30 mg/quinidine 10 mg (for 7 doses) on QTc prolongation was evaluated in a randomized, double-blind (except for moxifloxacin), placebo- and positive-controlled (400 mg moxifloxacin) crossover thorough QT study in 50 fasted normal healthy men and women with CYP2D6 extensive metabolizer (EM) genotype. Mean changes in QTcF were 6.8 ms for dextromethorphan 30 mg/quinidine 10 mg and 9.1 ms for the reference positive control (moxifloxacin). The maximum mean (95% upper confidence bound) difference from placebo after baseline correction was 10.2 (12.6) ms.

This test dose is adequate to represent the steady state exposure in patients with CYP2D6 extensive metabolizer phenotype. The effects of supratherapeutic doses of dextromethorphan/quinidine (30 mg/30mg and 60mg/60mg, for 7 doses) on QTc prolongation was evaluated in a randomized, placebo-controlled, double-blind, crossover design with an additional open-label positive control (400-mg moxifloxacin) arm in 36 healthy volunteers. The maximum mean (95% upper confidence bound) differences from placebo after baseline-correction were 10.2 (14.6) and 18.4 (22.7) ms following dextromethorphan/quinidine doses of 30 mg/30 mg and 60/60 mg, respectively.

The supratherapeutic doses are adequate to represent exposure increases due to drug-drug interactions and organ dysfunctions.

12.3Pharmacokinetics NUEDEXTA contains dextromethorphan and quinidine, both of which are metabolized primarily by liver enzymes. Quinidine’s primary pharmacological action in NUEDEXTA is to competitively inhibit the metabolism of dextromethorphan catalyzed by CYP2D6 in order to increase and prolong plasma concentrations of dextromethorphan [ see Warnings and Precautions ( 5.4 ), ( 5.8 ), and Clinical Pharmacology ( 12.5 ) ] . Studies were conducted with the individual components of NUEDEXTA in healthy subjects to determine single-dose and multiple-dose kinetics of orally administered dextromethorphan in combination with quinidine.

The increase in dextromethorphan levels appeared approximately dose proportional when the dextromethorphan dose was increased from 20 mg to 30 mg in the presence of 10 mg of quinidine. Absorption Following single and repeated combination doses of dextromethorphan 30 mg/quinidine 10 mg, dextromethorphan/quinidine -treated subjects had an approximately 20-fold increase in dextromethorphan exposure compared to dextromethorphan given without quinidine. Following repeated doses of dextromethorphan 30 mg/quinidine 10 mg and dextromethorphan 20 mg/ quinidine 10 mg (NUEDEXTA), maximal plasma concentrations (C max ) of dextromethorphan are reached approximately 3 to 4 hours after dosing and maximal plasma concentrations of quinidine are reached approximately 1 to 2 hours after dosing.

In extensive metabolizers, mean C max and AUC 0-12 values of dextromethorphan and dextrorphan increased as doses of dextromethorphan increased from 20 to 30 mg; mean C max and AUC 0-12 values of quinidine appeared similar. The mean plasma C max of quinidine following twice daily co-administration of dextromethorphan 30 mg/quinidine 10 mg in patients with PBA was within 1 to 3% of the concentrations required for antiarrhythmic efficacy (2 to 5 mcg/mL). NUEDEXTA may be taken without regard to meals as food does not affect the exposure of dextromethorphan and quinidine significantly.

Distribution After NUEDEXTA administration, protein binding remains essentially the same as that after administration of the individua…

🧬 Mechanism of Action 52 words

12.1Mechanism of Action Dextromethorphan (DM) is a sigma-1 receptor agonist and an uncompetitive NMDA receptor antagonist. Quinidine increases plasma levels of dextromethorphan by competitively inhibiting cytochrome P450 2D6, which catalyzes a major biotransformation pathway for dextromethorphan. The mechanism by which dextromethorphan exerts therapeutic effects in patients with pseudobulbar affect is unknown.

📦 How Supplied / Storage and Handling 69 words

16 HOW SUPPLIED/STORAGE AND HANDLING NUEDEXTA is supplied as brick red gelatin capsules imprinted with “DMQ 20-10”. NUEDEXTA is supplied in the following package configuration: Package Configuration Capsule Strength (mg) NDC Code Bottles of 60 (30 day supply) dextromethorphan 20 mg/ quinidine 10 mg 64597-301-60 Storage Store NUEDEXTA capsules at controlled room temperature, 25°C (77°F); excursions permitted to 15° - 30°C (59° - 86°F) [See USP Controlled Room Temperature].

📋 Description ~1 min read

11 DESCRIPTION NUEDEXTA is an oral formulation of dextromethorphan hydrobromide USP and quinidine sulfate USP in a fixed dose combination. Dextromethorphan hydrobromide is the pharmacologically active ingredient of NUEDEXTA that acts on the central nervous system (CNS). The chemical name is dextromethorphan hydrobromide: morphinan, 3-methoxy-17-methyl-, (9α, 13α, 14α), hydrobromide monohydrate.

Dextromethorphan hydrobromide has the empirical formula C 18 H 25 NO•HBr•H 2 O with a molecular weight of 370.33. The structural formula is: Quinidine sulfate is a specific inhibitor of CYP2D6-dependent oxidative metabolism used in NUEDEXTA to increase the systemic bioavailability of dextromethorphan. The chemical name is quinidine sulfate: cinchonan-9-o1, 6’-methoxy-, (9S) sulfate (2:1), (salt), dihydrate.

Quinidine sulfate dihydrate has the empirical formula of (C 20 H 24 N 2 O 2 ) 2 •H 2 SO 4 •2H 2 O with a molecular weight of 782.96. The structural formula is: The combination product, NUEDEXTA, is a white to off-white powder. NUEDEXTA is available for oral use as NUEDEXTA which contains 20 mg dextromethorphan hydrobromide and 10 mg quinidine sulfate.

The active ingredients are dextromethorphan hydrobromide monohydrate USP and quinidine sulfate dihydrate USP. Inactive ingredients in the capsule are croscarmellose sodium NF, microcrystalline cellulose NF, colloidal silicon dioxide NF, lactose monohydrate NF, and magnesium stearate NF. The structural formula for Dextromethorphan hydrobromide is the pharmacologically active ingredient of NUEDEXTA that acts on the central nervous system (CNS).

The chemical name is dextromethorphan hydrobromide: morphinan, 3-methoxy-17-methyl-, (9α, 13α, 14α), hydrobromide monohydrate. Dextromethorphan hydrobromide has the empirical formula C18H25NO•HBr•H2O with a molecular weight of 370.33. The structural formula for Quinidine sulfate is a specific inhibitor of CYP2D6-dependent oxidative metabolism used in NUEDEXTA to increase the systemic bioavailability of dextromethorphan.

The chemical name is quinidine sulfate: cinchonan-9-o1, 6’-methoxy-, (9S) sulfate (2:1), (salt), dihydrate. Quinidine sulfate dihydrate has the empirical formula of (C20H24N2O2)2•H2SO4•2H2O with a molecular weight of 782.96.

💬 Information for Patients ~2 min read

17 PATIENT COUNSELING INFORMATION Hypersensitivity Patients should be advised a hypersensitivity reaction to NUEDEXTA could occur. Patients should be instructed to seek medical attention immediately if they experience symptoms indicative of hypersensitivity after taking NUEDEXTA [ see Contraindications ( 4.2 ), Warnings and Precautions ( 5.1 ) ] . Cardiac effects Patients should be advised to consult their healthcare provider immediately if they feel faint or lose consciousness.

Patients should be counseled to inform their healthcare provider if they have any personal or family history of QTc prolongation [ see Contraindications ( 4.4 ), Warnings and Precautions ( 5.3 ) Drug Interactions ( 7 ) ] . Dizziness Patients should be advised that NUEDEXTA may cause dizziness. Precautions to reduce the risk of falls should be taken, particularly for patients with motor impairment affecting gait or a history of falls [ see Warnings and Precautions ( 5.5 ), Adverse Reactions ( 6.1 ) ] .

Drug Interactions Inform patients that NUEDEXTA increases the risk of adverse drug interactions. Instruct patients to inform their healthcare provider about all the medications that they are taking before taking NUEDEXTA. Before taking any new medications, patients should tell their healthcare provider that they are taking NUEDEXTA [ s ee Drug Interactions ( 7 ) ] .

Dosing Instructions Instruct patients to take NUEDEXTA exactly as prescribed. Instruct patients not to take more than 2 capsules in a 24-hour period and to make sure that there is an approximate 12-hour interval between doses, and not to take a double dose after they miss a dose [see Dosage and Administration ( 2.1 )] . General Patients should not share or give NUEDEXTA to others, even if they have the same symptoms, because it may harm them.

Advise patients to contact their healthcare provider if their PBA symptoms persist or worsen. Advise patients to keep this and all medications out of reach of children and pets. Marketed by: Avanir Pharmaceuticals, Inc.

Aliso Viejo, CA 92656 1-855-4NUEDEX (468-3339) Part No. MS-04305B AVANIR and NUEDEXTA are trademarks or registered trademarks of Avanir Pharmaceuticals, Inc. in the United States and other countries. U.S.

Patent Nos.: 8,227,484 and 7,659,282 ©2010-2019 Avanir Pharmaceuticals, Inc. All rights reserved.

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.