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Chlorzoxazone 500 mg Tablet, 15-count — NDC 53002-5760-05 package photo

Chlorzoxazone 500 mg Tablet, 15-count

by RPK Pharmaceuticals, Inc. · 15 TABLET in 1 BOTTLE (53002-5760-5)
NDC 53002-5760-05
🏷️ FDA NDC (as labeled) 53002-5760-5 billing pads the package segment with a zero
This package
Contains15-count Pack sizes4 compare ↓
Also comes in: 10 tablets 53002-5760-01 20 tablets 53002-5760-02 30 tablets 53002-5760-03
Rx only Generic Discontinued Non-controlled ⚠ Inactivated by FDA
🗂️ Data synced Jul 14, 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

⚠️
Excluded from the active FDA NDC Directory. FDA inactivated this product’s listing record, so it is excluded from the active NDC Directory. The listing was last certified through Dec 2024. 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) 53002-5760-5
Product NDC 53002-5760
11-digit billing NDC 53002576005
Application # ANDA089859
SPL Set ID 3c3c0279-a570-4ded-9f52-5ef345a6753b
Established class (EPC) Centrally-mediated Muscle Relaxation [PE], Muscle Relaxant
DEA schedule Non-controlled
Marketing category ANDA
Marketing status Discontinued
FDA listing status Inactivated by FDA (certified through Dec 2024)
Route ORAL
Dosage form TABLET
Substance CHLORZOXAZONE
TE code (Orange Book) AA · RLD · RS
Why two NDCs? The FDA registers this code as 53002-5760-5 — a 5-4-1 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 package segment → 53002-5760-05. 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.

🏭 Manufacturer & labeler

LabelerRPK Pharmaceuticals, Inc.
Application holderWATSON LABORATORIES INC
FDA applicationANDA089859 (ANDA)
Labeler code53002
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

📗 Our plain-language guide HelloPharmacist
  • Chlorzoxazone is a muscle relaxant used to help with short-term muscle pain and spasms — the kind that comes on suddenly from an injury or strain. It's meant to be used together wi...
  • Yes, drowsiness and dizziness are real possibilities with chlorzoxazone. Until you know how it affects you, it's best to avoid driving or operating machinery. Alcohol makes the dro...
  • Will this make me drowsy? Is it safe to drive?
  • This is actually a known and harmless side effect. Chlorzoxazone breaks down into a substance that can temporarily color your urine orange or reddish-brown. It has no known clinica...
📖 Read our full Chlorzoxazone 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 White
ShapeOval
ImprintWPI;39;68
Size17 mm
ScoringScored — splits in 2
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 F05Q2T2JA0
    Docusate sodium is a stool softener compound that helps medicines dissolve and move through the digestive tract. It acts as a surfactant, reducing surface tension in the intestines, and also serves as a wetting agent in tablet formulations.
  • 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 OJ245FE5EU
    Sodium benzoate is a salt derived from benzoic acid, a preservative. It's added to medicines to prevent growth of bacteria, fungi, and other microorganisms that could spoil the product.
  • UNII 5856J3G2A2
    A starch-based powder made from potatoes and processed with sodium. It acts as a disintegrant, helping the tablet or capsule break apart quickly in the stomach so the medicine can be absorbed.
  • UNII O8232NY3SJ
    A plant-based carbohydrate derived from corn kernels. It acts as a filler to add bulk, a binder to hold ingredients together, and a disintegrant to help the tablet break apart in your stomach for absorption.

7 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 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 · 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.
Try another pack size: 10 tablets 20 tablets 30 tablets
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
Chlorzoxazone 500 mgthis 53002-5760-05 RPK 15 tablets — AA Discontinued —
About this product: this is a generic version of the medicine. FDA equivalence ratings are shown when available, and other versions are listed above, least expensive first.
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

📍
2026
Currently FDA-listed
listed with the FDA
🔓
·
Generic on the market
this product is a generic
✅This is a generic drug

This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.

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 Chlorzoxazone — the program that covers self-administered drugs. 10 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 Chlorzoxazone. 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
$6.39M
Claims incl. refills
16.8K
Beneficiaries
10K
Spend / beneficiary
$639.03
Spend / claim
$380.55
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 CHLORZOXAZONE — the ingredient across all brands.

Top reported reactions

Nausea98
Dizziness95
Fatigue93
Pain92
Headache76
Anxiety66
Diarrhoea59

Age at onset

Adolescent2
Adult137
Elderly31

Reporter sex

1,295 reports
Male · 25%
Female · 75%
Unknown · 0%

Serious outcomes

Hospitalization365
Disabling44
Reports over time (by year) — tap or hover for the count & year
2021 2022 2024 2026 58 36
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
53002-5760-01 10 TABLET in 1 BOTTLE (53002-5760-1) 2018-10-01 Inactivated by FDA
53002-5760-02 20 TABLET in 1 BOTTLE (53002-5760-2) 2018-10-01 Inactivated by FDA
53002-5760-03 30 TABLET in 1 BOTTLE (53002-5760-3) 2018-10-01 Inactivated by FDA
53002-5760-05 You're viewing this 15 TABLET in 1 BOTTLE (53002-5760-5) 2018-10-01 Inactivated by FDA

You're viewing one of 4 pack sizes for this product.

Pack size FAQ

What quantity is in NDC 53002-5760-05?
NDC 53002-5760-05 is a 15-count package — 15 tablet in 1 bottle.
What is the difference between NDC 53002-5760-05 and NDC 53002-5760-01?
Both are Chlorzoxazone 500 mg Tablet — the drug itself is identical. NDC 53002-5760-05 is the 15-count package, while NDC 53002-5760-01 is the 10 tablets package.
What NDC number is used to bill for this package of Chlorzoxazone 500 mg Tablet?
Bill NDC 53002-5760-05 — the 11-digit billing format is 53002576005. Pharmacy and medical claims use the 11-digit form; the FDA label may print a shorter form of the same code.

🧭 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 53002-5760-5, 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: 53002-5760-05, written without dashes as 53002576005. 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 53002-5760-05, the first segment (53002) is the labeler code FDA assigned to RPK Pharmaceuticals, Inc.; the middle segment (5760) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (05) 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 3 other package presentations of this same product, including 10 tablets (53002-5760-01), 20 tablets (53002-5760-02), 30 tablets (53002-5760-03). 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?
RPK 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 ⏱️ Dosage and Administration ⛔ Contraindications ⚠️ Warnings 🤒 Adverse Reactions 🆘 Overdosage 🧬 Clinical Pharmacology 📦 How Supplied / Storage and Handling 📋 Description
🎯 Indications and Usage 55 words ▾

INDICATIONS Chlorzoxazone is indicated as an adjunct to rest, physical therapy, and other measures for the relief of discomfort associated with acute, painful musculoskeletal conditions. The mode of action of this drug has not been clearly identified, but may be related to its sedative properties. Chlorzoxazone does not directly relax tense skeletal muscles in man.

⏱️ Dosage and Administration 46 words ▾

DOSAGE AND ADMINISTRATION Usual Adult Dosage One tablet three or four times daily. If adequate response is not obtained with this dose, it may be increased to one and one-half tablets (750 mg) three or four times daily. As improvement occurs dosage can usually be reduced.

⛔ Contraindications 12 words ▾

CONTRAINDICATIONS Chlorzoxazone is contraindicated in patients with known intolerance to the drug.

⚠️ Warnings 163 words ▾

WARNINGS Serious (including fatal) hepatocellular toxicity has been reported rarely in patients receiving chlorzoxazone. The mechanism is unknown but appears to be idiosyncratic and unpredictable. Factors predisposing patients to this rare event are not known.

Patients should be instructed to report early signs and/or symptoms of hepatotoxicity such as fever, rash, anorexia, nausea, vomiting, fatigue, right upper quadrant pain, dark urine, or jaundice. Chlorzoxazone should be discontinued immediately and a physician consulted if any of these signs or symptoms develop. Chlorzoxazone use should also be discontinued if a patient develops abnormal liver enzymes (e.g., AST, ALT, alkaline phosphatase and bilirubin.) The concomitant use of alcohol or other central nervous system depressants may have an additive effect.

Usage in Pregnancy The safe use of chlorzoxazone has not been established with respect to the possible adverse effects upon fetal development. Therefore, it should be used in women of childbearing potential only when, in the judgment of the physician, the potential benefits outweigh the possible risks.

🤒 Adverse Reactions 112 words ▾

ADVERSE REACTIONS Chlorzoxazone containing products are usually well tolerated. It is possible in rare instances that chlorzoxazone may have been associated with gastrointestinal bleeding. Drowsiness, dizziness, lightheadedness, malaise, or over-stimulation may be noted by an occasional patient.

Rarely, allergic-type skin rashes, petechiae, or ecchymoses may develop during treatment. Angioneurotic edema or anaphylactic reactions are extremely rare. There is no evidence that the drug will cause renal damage.

Rarely, a patient may note discoloration of the urine resulting from a phenolic metabolite of chlorzoxazone. This finding is of no known clinical significance. To report SUSPECTED ADVERSE EVENTS, contact Actavis at 1-800-272-5525 or FDA at 1-800-FDA-1088 or http://www.fda.gov/ for voluntary reporting of adverse reactions.

🆘 Overdosage 165 words ▾

OVERDOSAGE Symptoms Initially, gastrointestinal disturbances such as nausea, vomiting, or diarrhea together with drowsiness, dizziness, lightheadedness or headache may occur. Early in the course there may be malaise or sluggishness followed by marked loss of muscle tone, making voluntary movement impossible. The deep tendon reflexes may be decreased or absent.

The sensorium remains intact, and there is no peripheral loss of sensation. Respiratory depression may occur with rapid, irregular respiration and intercostal and substernal retraction. The blood pressure is lowered, but shock has not been observed.

Treatment Gastric lavage or induction of emesis should be carried out, followed by administration of activated charcoal. Thereafter, treatment is entirely supportive. If respirations are depressed, oxygen and artificial respiration should be employed and a patent airway assured by use of an oropharyngeal airway or endotracheal tube.

Hypotension may be counteracted by use of dextran, plasma, concentrated albumin or a vasopressor agent such as norepinephrine. Cholinergic drugs or analeptic drugs are of no value and should not be used.

🧬 Clinical Pharmacology 151 words ▾

CLINICAL PHARMACOLOGY Chlorzoxazone is a centrally-acting agent for painful musculoskeletal conditions. Data available from animal experiments as well as human study indicate that chlorzoxazone acts primarily at the level of the spinal cord and subcortical areas of the brain where it inhibits multisynaptic reflex arcs involved in producing and maintaining skeletal muscle spasm of varied etiology. The clinical result is a reduction of the skeletal muscle spasm with relief of pain and increased mobility of the involved muscles.

Blood levels of chlorzoxazone can be detected in people during the first 30 minutes and peak levels may be reached, in the majority of the subjects, in about 1 to 2 hours after oral administration of chlorzoxazone. Chlorzoxazone is rapidly metabolized and is excreted in the urine, primarily in a conjugated form as the glucuronide. Less than one percent of a dose of chlorzoxazone is excreted unchanged in the urine in 24 hours.

📦 How Supplied / Storage and Handling 32 words ▾

HOW SUPPLIED Product: 53002-5760 NDC: 53002-5760-1 10 TABLET in a BOTTLE NDC: 53002-5760-5 15 TABLET in a BOTTLE NDC: 53002-5760-2 20 TABLET in a BOTTLE NDC: 53002-5760-3 30 TABLET in a BOTTLE

📋 Description 101 words ▾

DESCRIPTION Chlorzoxazone USP is a centrally acting skeletal muscle relaxant, available as tablets of 500 mg for oral administration. Its chemical name is 5-Chloro-2-benzoxazolinone, and its structural formula is: Chlorzoxazone Structural Formula C 7 H 4 CINO 2 MW 169.57 Chlorzoxazone USP is a white or practically white, practically odorless, crystalline powder. Chlorzoxazone is slightly soluble in water; sparingly soluble in alcohol, in isopropyl alcohol, and in methanol; soluble in solutions of alkali hydroxides and ammonia.

Chlorzoxazone tablets contain the inactive ingredients Docusate Sodium, Lactose (hydrous), Magnesium Stearate, Microcrystalline Cellulose, Pregelatinized Starch, Sodium Benzoate, and Sodium Starch Glycolate. Chlorzoxazone Structural Formula

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗
← 52993-0127-06 · Zinka, 53004-0440-03 · Specialty →
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.