Each caplet (capsule shaped tablet) contains:

Chlorzoxazone*...............................500 mg

Inactive ingredients: FD&C Blue No. 1, microcrystalline cellulose, docusate sodium, lactose (hydrous), magnesium stearate, sodium benzoate, sodium starch glycolate, pregelatinized corn starch, D&C Yellow No. 10.

*5-chlorobenzoxazolinone

Last updated on RxList: 4/18/2008

PARAFON FORTE DSC 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.

Usual Adult Dosage: One caplet three or four times daily. If adequate response is not obtained with this dose, it may be increased to 11/2 caplets (750 mg) three or four times daily. As improvement occurs dosage can usually be reduced.

PARAFON FORTE® DSC (chlorzoxazone) 500 mg caplets, (capsule shaped tablet, colored light green, imprinted "PARAFON FORTE DSC" and "McNEIL," scored).

NDC 0045-0325-60, bottles of 100.

Dispense in tight container as defined in the official compendium. Store at controlled room temperature (15°-30°C, 59°-86°F).

OMP DIVISION, ORTHO-McNEIL PHARMACEUTICAL, INC. Raritan, NJ 08869. Revised August 2000. FDA Rev date: 12/1/2000

Last updated on RxList: 4/18/2008

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.

No information provided

Last updated on RxList: 4/18/2008

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 PARAFON FORTE DSC 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.

PARAFON FORTE DSC chlorzoxazone should be used with caution in patients with known allergies or with a history of allergic reactions to drugs. If a 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.

Last updated on RxList: 4/18/2008

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.

PARAFON FORTE DSC chlorzoxazone is contraindicated in patients with known intolerance to the drug.

Last updated on RxList: 4/18/2008

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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.

Last updated on RxList: 4/18/2008

No information provided. Please refer to the WARNINGS and PRECAUTIONS sections.

Last updated on RxList: 4/18/2008

IMPORTANT NOTE: This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your health care professional. Always seek the advice of your health care professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your health care professional. This information does not contain any assurances that this product is safe, effective, or appropriate for you.

CHLORZOXAZONE - ORAL

(klor-ZOX-uh-zone)

COMMON BRAND NAME(S): Paraflex, Parafon Forte, Relaxazone, Remular-S

USES: This medication is used to treat pain and discomfort from muscle injuries such as strains, sprains, and spasms. It provides temporary relief and is usually used along with rest, physical therapy, and other treatments (e.g., nonsteroidal anti-inflammatory medication). This medication relaxes tight muscles and relieves pain, cramping, and stiffness so you can move around more and get back to doing your daily activities. Chlorzoxazone belongs to a class of drugs called muscle relaxants. It is thought to work on the nerves to relieve muscle pain. It may also relieve pain by calming your nervous system.

HOW TO USE: Take this medication by mouth, usually 3 or 4 times daily or as directed by your doctor.

The dosage is based on your medical condition and response to therapy. Do not increase your dose, take it more often, or take it for longer than prescribed. This may increase your risk for side effects.

Inform your doctor if your condition does not improve or if it worsens.

SIDE EFFECTS: Drowsiness, dizziness, tiredness, upset stomach, or headache may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

This medication may temporarily cause your urine to turn orange or reddish-purple. This effect is harmless and will go away when the medication is stopped.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor immediately if any of these rare but very serious side effects occur: black/bloody stools, vomit that looks like coffee grounds, easy bruising/bleeding, signs of infection (e.g., fever, chills, persistent sore throat).

This medication may rarely cause very serious (possibly fatal) liver disease. Stop taking this medication and seek immediate medical attention if any of these side effects occur: loss of appetite, persistent/severe tiredness, persistent nausea/vomiting, stomach/abdominal pain, yellowing eyes/skin, dark urine.

A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching, swelling, severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

Contact your doctor for medical advice about side effects. The following numbers do not provide medical advice, but in the US you may report side effects to the Food and Drug Administration (FDA) at 1-800-FDA-1088. In Canada, you may call Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking chlorzoxazone, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: liver disease.

This drug may make you dizzy or drowsy. Use caution while driving, using machinery, or doing any activity that requires alertness. Limit alcoholic beverages.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor or pharmacist first.

Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use.

Tell your doctor or pharmacist if you also take drugs that cause drowsiness such as: certain antihistamines (e.g., diphenhydramine), anti-seizure drugs (e.g., carbamazepine), medicine for sleep or anxiety (e.g., alprazolam, diazepam, zolpidem), other muscle relaxants, narcotic pain relievers (e.g., codeine), psychiatric medicines (e.g., chlorpromazine, risperidone, amitriptyline, trazodone).

Check the labels on all your medicines (e.g., cough-and-cold products) because they may contain drowsiness-causing ingredients. Ask your pharmacist about using those products safely.

This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.

OVERDOSE: If overdose is suspected, contact your local poison control center or emergency room immediately. US residents should call the US National Poison Hotline at 1-800-222-1222. Canada residents should call a provincial poison control center. Symptoms of overdose may include: nausea/vomiting, diarrhea, severe drowsiness, loss of muscle tone, fast/irregular breathing.

NOTES: Do not share this medication with others.

If you are taking this medication for a long time, laboratory and/or medical tests (e.g., liver function tests) should be performed periodically to check for side effects. Consult your doctor for more details.

MISSED DOSE: If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.

STORAGE: Store at room temperature between 59-86 degrees F (15-30 degrees C) away from light and moisture. Do not store in the bathroom. Keep all medicines away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.

Information last revised July 2008 Copyright(c) 2008 First DataBank, Inc.