Chlorzoxazone: Uses, Side Effects, Dosage - Drugvu

ℹ️ Compiled from public regulatory records · Last regulator revision: March 16, 2025🚩 Report this page

Chlorzoxazone

Oxazol, Thiazine, and Triazine Derivatives

US FDA

Drug class: Oxazol, Thiazine, and Triazine Derivatives
Availability: Prescription only
Routes: Oral
Markets covered: 1
Products on record: 3
FDA reports (12 mo): 46

M03BBOxazol, Thiazine, and Triazine Derivatives

Overview

Chlorzoxazone is an active pharmaceutical ingredient in the Oxazol, Thiazine, and Triazine Derivatives group (M03BB). The information below is compiled per regulator from the product labels on record, with direct links to the original documents.

Regulatory status by market

Market	Regulator	Products	Last revision
US United States	FDA	3	March 16, 2025

USUnited States· FDA

3 products

Uses

USOfficial regulatory label· revised March 1, 2025[1]

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.

How to take

Drug interactions

Known interactions involving Chlorzoxazone. Select one for details. This list is informational and not a complete interaction checker.

Alfentanil Benzhydrocodone Buprenorphine Butorphanol Codeine Dezocine Dihydrocodeine Fentanyl Hydrocodone Hydromorphone Leflunomide Lemborexant Levorphanol Lomitapide Meperidine Methadone Mipomersen Morphine Nalbuphine Oliceridine Oxycodone Oxymorphone Pentazocine Pexidartinib Propoxyphene Remifentanil Sufentanil Tapentadol Teriflunomide Tramadol Acebutolol Aldesleukin Alfuzosin Alprazolam Amitriptyline Amobarbital Amoxapine Apomorphine Apraclonidine Aripiprazole Asenapine Asparaginase Atenolol Azatadine Azilsartan Baclofen Bedaquiline Benazepril Bepridil Betaxolol Biperiden Bisoprolol Botulinum Toxin Type A Botulinum Toxin Type B Brentuximab Vedotin Brexanolone Brexpiprazole Brimonidine Brivaracetam Bromocriptine Brompheniramine Buspirone Butabarbital Butalbital Calaspargase Pegol Cannabidiol Carbamazepine Carbinoxamine Cariprazine Carisoprodol Carteolol Carvedilol Cenobamate Ceritinib Cetirizine Chlordiazepoxide Chlormezanone Chlorpheniramine Chlorpromazine Citalopram Clemastine Clevidipine Clobazam Clofarabine Clomipramine Clonazepam Clonidine Clorazepate Clozapine Cyclizine Cyproheptadine Deserpidine Desipramine Desvenlafaxine Deutetrabenazine Dexbrompheniramine Dexmedetomidine Dextromethorphan Diazepam Diphenhydramine Disulfiram Doxazosin Doxepin Doxylamine Dronabinol Droperidol Duloxetine Efavirenz Entacapone Eplerenone Escitalopram Esketamine Eslicarbazepine Esmolol Estazolam Eszopiclone Ethacrynate Ethanol Ethosuximide Ethotoin Ezogabine Felbamate Fenoldopam Flavoxate Flibanserin Fluoxetine Fluphenazine Flurazepam Fluvoxamine Fosphenytoin Gabapentin Guanabenz Guanadrel Guanfacine Halazepam Haloperidol Hydroxyzine Idelalisib Ifosfamide Iloperidone Imipramine Interferon Beta-1a Interferon Beta-1b Isocarboxazid Isoniazid Ketamine Labetalol Lamotrigine Lasmiditan Levamlodipine Levetiracetam Levocetirizine Lithium Carbonate Lofexidine Lorazepam Loxapine Lumateperone Lurasidone Maprotiline Mephenytoin Mephobarbital Meprobamate Mesoridazine Methotrexate Methsuximide Metoclopramide Metoprolol Metyrosine Midazolam Mirtazapine Molindone Nabilone Nadolol Naltrexone Nebivolol Nefazodone Nimodipine Nortriptyline Olanzapine Olopatadine Opicapone Opium Oxazepam Oxcarbazepine Paliperidone Paraldehyde Paramethadione Paroxetine Pegaspargase Peginterferon Beta-1a Penbutolol Pentobarbital Perampanel Pergolide Perphenazine Phenacemide Phenelzine Phenobarbital Phensuximide Phenyltoloxamine Phenytoin Pimozide Pindolol Pramipexole Prazosin Pregabalin Primidone Prochlorperazine Procyclidine Promazine Promethazine Propiomazine Propranolol Protriptyline Pyrilamine Quazepam Quetiapine Ramelteon Rasagiline Remdesivir Remimazolam Reserpine Risperidone Ropinirole Rotigotine Rufinamide Secobarbital Sertraline Sibutramine Silodosin Sotalol Stiripentol Suvorexant Tamsulosin Tasimelteon Telmisartan Temazepam Terazosin Tetrabenazine Thalidomide

Showing 240 of 303. Type above to find a specific drug.

Interaction data compiled from DDInter (academic, CC-BY). Severity classification only - this is not a complete interaction checker and not medical advice.

Sources & citations

[1]FDA DailyMed · 0a8ee5fa-f393-45… · revised March 1, 2025 [PDF]
[2]OpenFDA adverse-event reports (US), 12 months ending June 4, 2026.

Information on this page is compiled from public regulatory records. Drugvu is not affiliated with any regulator or pharmaceutical manufacturer. This is not medical advice. Always consult a qualified healthcare professional.

Side effects & warnings

USOfficial regulatory label· Adverse reactions· revised March 1, 2025[1]

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 Aurobindo Pharma USA, Inc. gov/ for voluntary reporting of adverse reactions.

USOfficial regulatory label· Warnings and precautions· revised March 1, 2025[1]

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.
) 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.

This is not medical advice. Consult a qualified healthcare professional.