CHLORZOXAZONE

openFDA label record#

This page contains supplementary openFDA label data. For the canonical label presentation, use the corresponding DailyMed Structured Product Label.

Verified complete openFDA source JSON (canonical bytes are SHA-256 checked before publication)

Brand name
CHLORZOXAZONE
Generic name
CHLORZOXAZONE
Manufacturer
A-S Medication Solutions
Product type
HUMAN PRESCRIPTION DRUG
SPL set ID
d0210638-b828-4c05-9669-fd61ef987317
SPL ID
ff4525dd-9c48-4151-970b-9a184e1f4bf4
Version
1
Effective date
2025-02-04
Source export date
2026-09-28
Source partition
11
Source file
https://download.open.fda.gov/drug/label/drug-label-0011-of-0014.json.zip
Source object key
raw/openfda/drug-label/2026-09-28/aa96b5a2be6b394393acd0090f6948bdf99e0e8e00666f81608929c8fa83db77/drug-label-0011-of-0014.json.zip
Source manifest SHA-256
cd2e66336a5cd2223fa3995098fdbdb84c6a7ee5c0a4addb236ccb22dd1e6887
Import run
20260929T050834Z
Imported at
2026-09-29 06:16:06
Harmonized routes table
Harmonized routes
ORAL

Warnings cross-check#

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Warnings sections page 1 of 1 · 1 matching rows.

warnings

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 judgement of the physician, the potential benefits outweigh the possible risks.

Adverse reactions cross-check#

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Adverse reactions sections page 1 of 1 · 1 matching rows.

adverse reactions

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. To report SUSPECTED ADVERSE REACTIONS, contact Rising Pharma Holdings, Inc. at 1-844-874-7464 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Reported adverse events (FAERS/openFDA)#

Adverse event summaries are temporarily unavailable. Other product information remains available.