NDC 68462-725 Chlorzoxazone

Tablet Oral

NDC Product Code 68462-725

NDC 68462-725-01

Package Description: 100 TABLET in 1 BOTTLE, PLASTIC

NDC 68462-725-05

Package Description: 500 TABLET in 1 BOTTLE, PLASTIC

NDC Product Information

Chlorzoxazone with NDC 68462-725 is a human prescription drug product labeled by Glenmark Pharmaceuticals Inc., Usa. The product's dosage form is tablet and is administered via oral form.

Dosage Form: Tablet - A solid dosage form containing medicinal substances with or without suitable diluents.

Product Type: Human Prescription Drug What kind of product is this?
Indicates the type of product, such as Human Prescription Drug or Human Over the Counter Drug. This data element matches the “Document Type” field of the Structured Product Listing.

Chlorzoxazone Active Ingredient(s)

What is the Active Ingredient(s) List?
This is the active ingredient list. Each ingredient name is the preferred term of the UNII code submitted.

RxNorm Crosswalk

What is RxNorm?
RxNorm is a normalized naming system for generic and branded drugs that assigns unique concept identifier(s) (RxCUI) to each NDC.

The RxNorm Crosswalk for this NDC code indicates multiple concept unique identifiers (RXCUI) are associated with this product:

Inactive Ingredient(s)

About the Inactive Ingredient(s)
The inactive ingredients are all the component of a medicinal product OTHER than the active ingredient(s). The acronym "UNII" stands for “Unique Ingredient Identifier” and is used to identify each inactive ingredient present in a product.


Administration Route(s)

What are the Administration Route(s)?
The translation of the route code submitted by the firm, indicating route of administration.

  • Oral - Administration to or by way of the mouth.

Pharmacologic Class(es)

What is a Pharmacological Class?
These are the reported pharmacological class categories corresponding to the SubstanceNames listed above.

Product Labeler Information

What is the Labeler Name?
Name of Company corresponding to the labeler code segment of the Product NDC.

Labeler Name: Glenmark Pharmaceuticals Inc., Usa
Labeler Code: 68462
FDA Application Number: ANDA212185 What is the FDA Application Number?
This corresponds to the NDA, ANDA, or BLA number reported by the labeler for products which have the corresponding Marketing Category designated. If the designated Marketing Category is OTC Monograph Final or OTC Monograph Not Final, then the Application number will be the CFR citation corresponding to the appropriate Monograph (e.g. “part 341”). For unapproved drugs, this field will be null.

Marketing Category: ANDA - A product marketed under an approved Abbreviated New Drug Application. What is the Marketing Category?
Product types are broken down into several potential Marketing Categories, such as NDA/ANDA/BLA, OTC Monograph, or Unapproved Drug. One and only one Marketing Category may be chosen for a product, not all marketing categories are available to all product types. Currently, only final marketed product categories are included. The complete list of codes and translations can be found at www.fda.gov/edrls under Structured Product Labeling Resources.

Start Marketing Date: 05-26-2020 What is the Start Marketing Date?
This is the date that the labeler indicates was the start of its marketing of the drug product.

End Marketing Date: 09-01-2022 What is the End Marketing Date?
This is the date the product will no longer be available on the market. If a product is no longer being manufactured, in most cases, the FDA recommends firms use the expiration date of the last lot produced as the EndMarketingDate, to reflect the potential for drug product to remain available after manufacturing has ceased. Products that are the subject of ongoing manufacturing will not ordinarily have any EndMarketingDate. Products with a value in the EndMarketingDate will be removed from the NDC Directory when the EndMarketingDate is reached.

Exclude Flag: N - NO What is the NDC Exclude Flag?
This field indicates whether the product has been removed/excluded from the NDC Directory for failure to respond to FDA"s requests for correction to deficient or non-compliant submissions ("Y"), or because the listing certification is expired ("E"), or because the listing data was inactivated by FDA ("I"). Values = "Y", "N", "E", or "I".

* Please review the disclaimer below.

Chlorzoxazone Product Labeling Information

The product labeling information includes all published material associated to a drug. Product labeling documents include information like generic names, active ingredients, ingredient strength dosage, routes of administration, appearance, usage, warnings, inactive ingredients, etc.

Product Labeling Index


For Painful Musculoskeletal ConditionsPRESCRIBING INFORMATION

Manufactured by:Glenmark Pharmaceuticals Inc., USA4147 Goldmine RoadMonroe, NC 28110Manufactured for:Glenmark Pharmaceuticals Inc., USA Mahwah, NJ 07430Questions? 1 (888) 721-7115www.glenmarkpharma-us.comJanuary 2020


Each 375 mg Chlorzoxazone Tablet USP contains: chlorzoxazone USP, 375 mg.Each 750 mg Chlorzoxazone Tablet USP contains: chlorzoxazone USP, 750 mg.Chemical Name: 5-Chloro-2-benzoxazolinone.Structural Formula:Molecular Formula: C7H4ClNO2Molecular Weight: 169.56 g/molChlorzoxazone USP is a white or practically white, practically odorless, crystalline powder.Chlorzoxazone USP is slightly soluble in water; sparingly soluble in alcohol, in isopropyl alcohol, and in methanol; soluble in solutions of alkali hydroxides and ammonia.Inactive ingredients: anhydrous lactose, colloidal silicon dioxide, croscarmellose sodium, docusate sodium, magnesium stearate, microcrystalline cellulose, pregelatinized starch and sodium benzoate.

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.

Indications And Usage

Chlorzoxazone tablets are 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.


Chlorzoxazone tablets are contraindicated in patients with known intolerance to the drug.


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 hepatoxicity such as fever, rash, anorexia, nausea, vomiting, fatigue, right upper quadrant pain, dark urine, or jaundice. Chlorzoxazone tablets should be discontinued immediately and a physician consulted if any of these signs or symptoms develop. Chlorzoxazone tablets 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 judgement of the physician, the potential benefits outweigh the possible risks.


Chlorzoxazone tablets should be used with caution in patients with known allergies or with a history of allergic reactions to drugs. If sensitivity reaction occurs such as urticaria, redness, or itching of the skin, the drug should be stopped.If any symptoms suggestive of liver dysfunction are observed, the drug should be discontinued.

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, light-headedness, malaise, or overstimulation 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.


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 intercostals 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.

Dosage And Administration

Usual Adult DosageChlorzoxazone Tablets USP, 375 mg:One tablet, three or four times daily. If adequate response is not obtained with this dose, the 375 mg tablets may be increased to two tablets (750 mg) three or four times daily. As improvement occurs, dosage can usually be reduced.Chlorzoxazone Tablets USP, 750 mg:1/3 tablet (250 mg) three or four times daily. Initial dosage for painful musculoskeletal conditions should be 2/3 tablet (500 mg) three or four times daily. If adequate response is not obtained with this dose, it may be increased to one tablet (750 mg) three or four times daily. As improvement occurs dosage can usually be reduced.

How Supplied

  • Chlorzoxazone Tablets USP are supplied as follows:375 mgA white to off-white capsule shaped tablet, debossed with “G” on one side and “724” on the other side, in bottles of 100 and 500 tablets. 100’s HDPE bottle packNDC 68462-724-01 500’s HDPE bottle packNDC 68462-724-05750 mgA white to off-white capsule shaped tablet, debossed with “G” and “725” on the bisected scored side and plain on the trisected scored side, in bottles of 100 and 500 tablets. 100’s HDPE bottle packNDC 68462-725-01 500’s HDPE bottle packNDC 68462-725-05Dispense in a tight container as defined in the official compendium.Store at 20°C to 25°C (68°F to 77°F) [see USP Controlled Room Temperature].

Package/Label Display Panel

Chlorzoxazone Tablets, USP, 375 mgNDC 68462-724-01Bottle label-100 tablets

Chlorzoxazone Tablets, USP, 750 mgNDC 68462-725-01Bottle label-100 tablets

* Please review the disclaimer below.