Parafon Forte DSC Oral: Uses, Side Effects, Interactions, Pictures, Warnings & Dosing

Uses

Chlorzoxazone is used to treat muscle spasms/pain. It is usually used along with rest, physical therapy, and other treatment. It works by helping to relax the muscles.

How to use Parafon Forte DSC 500 Mg Tablet

Take this medication by mouth with or without food as directed by your doctor. Do not increase your dose or use this drug more often or for longer than prescribed. Your condition will not improve any faster, and your risk of side effects will increase.

The dosage is based on your medical condition and response to treatment.

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

Side Effects

Drowsiness, dizziness, lightheadedness, tiredness, upset stomach, or headache may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

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

Remember that this medication has been prescribed because your doctor 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 right away if you have any serious side effects, including: confusion, black/bloody stools, vomit that looks like coffee grounds, easy bruising/bleeding, signs of infection (such as sore throat that doesn’t go away, fever).

This medication may rarely cause very serious (possibly fatal) liver disease. Stop taking this medication and get medical help right away if you develop symptoms of liver disease, including: nausea/vomiting that doesn’t stop, stomach/abdominal pain, yellowing eyes/skin, dark urine.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), 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.

In the US – Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada – Call your doctor for medical advice about side effects. You may report side effects to 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 product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: liver disease.

This drug may make you dizzy or drowsy. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Older adults may be more sensitive to the side effects of this drug, especially drowsiness, or confusion. These side effects can increase the risk of falling.

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

It is unknown if this drug passes into breast milk. Consult your doctor before breast-feeding.

Interactions

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor’s approval.

Tell your doctor or pharmacist if you are taking other products that cause drowsiness such as opioid pain or cough relievers (such as codeine, hydrocodone), alcohol, marijuana (cannabis), drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), other muscle relaxants (such as carisoprodol, cyclobenzaprine), or antihistamines (such as cetirizine, diphenhydramine).

Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.

Does Parafon Forte DSC 500 Mg Tablet interact with other drugs you are taking?

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Overdose

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: nausea/vomiting, severe drowsiness, muscle weakness, fast/irregular breathing.

Do not share this medication with others.

This medication has been prescribed for your current condition only. Do not use it later for another condition unless your doctor directs you to do so. A different medication may be necessary in that case.

If you are taking this medication for a long time, lab and/or medical tests (such as liver function) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.

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. Take your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications 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.

Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, except as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

Parafon Forte DSC: Package Insert

Package insert / product label
Generic name: chlorzoxazone
Dosage form: caplets
Drug class: Skeletal muscle relaxants

Medically reviewed by Drugs.com. Last updated on Mar 22, 2023.

The Parafon Forte DSC brand name has been discontinued in the U.S. If generic versions of this product have been approved by the FDA, there may be generic equivalents available.

On This Page

• Description
• Indications and Usage
• Contraindications
• Warnings
• Precautions
• Adverse Reactions/Side Effects
• Dosage and Administration
• Overdosage
• How Supplied/Storage and Handling

For Painful Musculoskeletal Conditions

Parafon Forte DSC Description

Each caplet (capsule shaped tablet) contains:

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.

ACTIONS

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

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.

Contraindications

Parafon Forte DSC chlorzoxazone is contraindicated in patients with known intolerance to the drug.

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 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.

Precautions

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.

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 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.

Parafon Forte DSC Dosage and Administration

Usual Adult Dosage

One caplet three or four times daily. If adequate response is not obtained with this dose, it may be increased to 1 ½ caplets (750 mg) three or four times daily. As improvement occurs dosage can usually be reduced.

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.

How is Parafon Forte DSC Supplied

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

NDC 50458-625-60, bottles of 100.

Dispense in tight container as defined in the official compendium.

Store at controlled room temperature (15°–30°C, 59°–86°F).

Product of Taiwan.

Manufactured by:
Janssen Ortho, LLC
Gurabo, Puerto Rico 00778

Manufactured for:
Janssen Pharmaceuticals, Inc.
Titusville, NJ 08560

© Janssen Pharmaceuticals, Inc.

Revised: March 2012

PRINCIPAL DISPLAY PANEL – 500 mg Caplet Bottle Label

NDC 50458-625-60

Parafon
Forte® DSC
(CHLORZOXAZONE)

500 mg

100 caplets

Rx only

janssen

Parafon Forte DSC chlorzoxazone tablet

Product Information Product Type HUMAN PRESCRIPTION DRUG LABEL Item Code (Source) NDC:50458-625 Route of Administration ORAL DEA Schedule

Active Ingredient/Active Moiety Ingredient Name Basis of Strength Strength chlorzoxazone (chlorzoxazone) chlorzoxazone 500 mg

Inactive Ingredients Ingredient Name Strength cellulose, microcrystalline FD&C Blue No. 1 docusate sodium lactose magnesium stearate sodium benzoate starch, corn D&C Yellow No. 10 sodium starch glycolate type A potato

Product Characteristics Color GREEN (light green) Score 2 pieces Shape OVAL (capsule shaped) Size 17mm Flavor Imprint Code PARAFON;FORTE;DSC;MCNEIL Contains

Packaging # Item Code Package Description 1 NDC:50458-625-60 100 TABLET in 1 BOTTLE

Marketing Information Marketing Category Application Number or Monograph Citation Marketing Start Date Marketing End Date NDA NDA011529 06/15/1987

Labeler – Janssen Pharmaceuticals, Inc. (063137772)

Janssen Pharmaceuticals, Inc.

More about Parafon Forte DSC (chlorzoxazone)

• Check interactions
• Compare alternatives
• Reviews (3)
• Drug images
• Side effects
• Dosage information
• During pregnancy
• Drug class: skeletal muscle relaxants

Patient resources

• Advanced Reading
• Parafon Forte DSC

Professional resources

• Prescribing Information
• Chlorzoxazone (FDA)

Other brands

Lorzone

Related treatment guides

• Muscle Spasm

Medical Disclaimer

Strong Parafon (Chlorzoxazone): Uses, Dosage, Side Effects, Interactions, Warning

• Generic Name: Chlorzoxazone
• Brand Name: Parafon Forte

• Product Description
• Indications and Dosage
• Adverse effects and drug interactions
• Warnings and Precautions
• Overdose and Contraindications
• Clinical Pharmacology
• Medication Guide

Product Description

DSC STRONG PARAFON
(chlorzoxazone) Caplets 500mg

DESCRIPTION

Each capsule ( tablet in the form of a capsule) contains:

Chlorzoxazone * 500 mg

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

* 5-chlorobenzoxazolinone

Indications and Dosage

INDICATIONS

Parafon FORTE DSC Chlorzoxazone is indicated as an adjunct to rest, physical therapy and other measures to relieve discomfort associated with acute, painful musculoskeletal problems. The mechanism of action of this drug has not been precisely established, but may be related to its sedative properties. Chlorzoxazone does not directly relax tense human skeletal muscles.

DOSAGE AND ADMINISTRATION

Usual adult dosage

One capsule three or four times a day. If an adequate response is not obtained with this dose, it may be increased to 1½ caplets (750 mg) three or four times a day. As improvement occurs, the dosage can usually be reduced.

HOW SUPPLIED

FORAFON FORTE DSC (chlorzoxazone) 500 mg caplets (capsule shaped tablet, light green, labeled “PARAFON FORTE DSC” and “McNEIL”, under evaluation).

NDC 50458-625-60, bottles of 100 pcs.

Pour into a tightly closed container as defined in the official guide.

Store at controlled room temperature (15-30°C, 59-86°F).

Manufactured by: Janssen Ortho, LLC, Gurabo, Puerto Rico, 00778 Manufactured for: Janssen Pharmaceuticals, Inc. Titusville, NJ 08560 Revised: March 2012

Adverse effects and drug interactions

SIDE EFFECTS

Products containing chlorzoxazone are generally well tolerated. In rare cases, it is possible that chlorzoxazone has been associated with gastrointestinal bleeding. Occasionally, patients may report drowsiness, dizziness, dizziness, malaise, or overstimulation. In rare cases, allergic-type skin rashes, petechiae, or ecchymosis may develop during treatment. Angioedema or anaphylactic reactions are extremely rare. There is no evidence that the drug can cause kidney damage. In rare cases, the patient may notice a discoloration of the urine due to the phenolic metabolite of chlorzoxazone. This finding has no known clinical significance.

DRUG INTERACTIONS

No information provided.

Warnings and Precautions

WARNINGS

Serious (including fatal) hepatocellular toxicity has rarely been reported in patients receiving chlorzoxazone. The mechanism is unknown, but seems unique and unpredictable. Factors predisposing patients to this rare event are unknown. 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. If any of these signs or symptoms occur, stop taking chlorzoxazone immediately and consult your doctor. Chlorzoxazone should also be discontinued if the patient develops abnormal liver enzymes (eg, AST, ALT, alkaline phosphatase, and bilirubin).

Concomitant use of alcohol or other central nervous system depressants may have an additive effect.

Use in Pregnancy

The safe use of Chlorzoxazone PARAFON FORTE DSC has not been established with respect to possible adverse effects on fetal development. Therefore, it should be used in women of childbearing potential only when, in the opinion of the physician, the potential benefits outweigh the possible risks.

PRECAUTIONS

Chlorzoxazone PARAFON FORTE DSC should be used with caution in patients with a known allergy or a history of allergic drug reactions. If a hypersensitivity reaction occurs, such as urticaria, redness or itching of the skin, the drug should be discontinued.

If any symptoms suggestive of abnormal liver function are observed, the drug should be discontinued.

Overdose and contraindications

OVERDOSE

Symptoms

Gastrointestinal disturbances such as nausea, vomiting or diarrhea may initially occur, together with drowsiness, dizziness, vertigo or headache. At the beginning of the course, there may be malaise or lethargy, followed by a noticeable loss of muscle tone, which makes voluntary movements impossible. Deep tendon jerks may be reduced or absent. The sensorium remains intact and there is no peripheral sensory loss. Respiratory depression may be accompanied by rapid, irregular breathing and retraction of the intercostal and substernal muscles. Arterial pressure is lowered, but shock is not observed.

Maintenance

Gastric lavage or induction of vomiting followed by activated charcoal should be performed. Thereafter, treatment is fully supportive. If breathing is depressed, oxygen and artificial respiration should be used, and the airway should be secured with an oropharyngeal airway or endotracheal tube. Hypotension can be counteracted using dextran, plasma, concentrated albumin, or a vasoconstrictor such as norepinephrine. Cholinergic or analeptic drugs are of no value and should not be used.

CONTRAINDICATIONS

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