DRUGS & SUPPLEMENTS
Methocarbamol TABLETS, USP
Methocarbamol Tablets, USP, a carbamate derivative of guaifenesin, are a central nervous system (CNS) depressant with sedative and musculoskeletal relaxant properties. The structural formula is:
The chemical name for Methocarbamol is 3-(2-Methoxyphenoxy)-1,2-propanediol 1-carbamate and has the empirical formula C11H15NO5. Its molecular weight is 241.24.
Methocarbamol is a white powder, sparingly soluble in water and chloroform, soluble in alcohol (only with heating) and propylene glycol, and insoluble in benzene and n-hexane.
Each tablet, for oral administration, contains 500 mg or 750 mg of Methocarbamol, USP. In addition each tablet contains the following inactive ingredients: Colloidal Silicon Dioxide, Lactose Monohydrate, Magnesium Stearate, Methylcellulose, Microcrystalline Cellulose, Pregelatinized Starch and Sodium Starch Glycolate.
The mechanism of action of Methocarbamol in humans has not been established, but may be due to general central nervous system depression. It has no direct action on the contractile mechanism of striated muscle, the motor end plate or the nerve fiber.
In healthy volunteers, the plasma clearance of Methocarbamol ranges between 0.20 and 0.80 L/h/kg, the mean plasma elimination half-life ranges between 1 and 2 hours, and the plasma protein binding ranges between 46% and 50%.
Methocarbamol is metabolized via dealkylation and hydroxylation. Conjugation of Methocarbamol also is likely. Essentially all Methocarbamol metabolites are eliminated in the urine. Small amounts of unchanged Methocarbamol also are excreted in the urine.
Special Populations :
The mean elimination half-life of Methocarbamol in elderly healthy volunteers (mean (± SD) age, 69 (± 4) years) was slightly prolonged compared to a younger (mean (± SD) age, 53.3 (± 8.8) years), healthy population (1.5 (±0.4) hours versus 1.1 (±0.27) hours, respectively). The fraction of bound Methocarbamol was slightly decreased in the elderly versus younger volunteers (41 to 43% versus 46 to 50%, respectively).
The clearance of Methocarbamol in 8 renally-impaired patients on maintenance hemodialysis was reduced about 40% compared to 17 normal subjects, although the mean (±SD) elimination half-life in these two groups was similar: 1.2 (±0.6) versus 1.1 (±0.3) hours, respectively.
In 8 patients with cirrhosis secondary to alcohol abuse, the mean total clearance of Methocarbamol was reduced approximately 70% compared to that obtained in 8 age- and weight-matched normal subjects. The mean (±SD) elimination half-life in the cirrhotic patients and the normal subjects was 3.38 (±1.62) hours and 1.11 (±0.27) hours, respectively. The percent of Methocarbamol bound to plasma proteins was decreased to approximately 40 to 45% compared to 46 to 50% in the normal subjects.
INDICATIONS AND USAGE:
Methocarbamol 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 Methocarbamol has not been clearly identified, but may be related to its sedative properties. Methocarbamol does not directly relax tense skeletal muscles in man.
Methocarbamol Tablets are contraindicated in patients hypersensitive to Methocarbamol or to any of the tablet components.
Since Methocarbamol may possess a general CNS depressant effect, patients receiving Methocarbamol Tablets should be cautioned about combined effects with alcohol and other CNS depressants.
Safe use of Methocarbamol Tablets has not been established with regard to possible adverse effects upon fetal development. There have been reports of fetal and congenital abnormalities following in utero exposure to Methocarbamol. Therefore, Methocarbamol Tablets should not be used in women who are or may become pregnant and particularly during early pregnancy unless in the judgment of the physician the potential benefits outweigh the possible hazards.
Use in Activities Requiring Mental Alertness :
Methocarbamol may impair mental and/or physical abilities required for performance of hazardous tasks, such as operating machinery or driving a motor vehicle. Patients should be cautioned about operating machinery, including automobiles, until they are reasonably certain that Methocarbamol therapy does not adversely affect their ability to engage in such activities.
Information for Patients:
Patients should be cautioned that Methocarbamol may cause drowsiness or dizziness, which may impair their ability to operate motor vehicles or machinery.
Because Methocarbamol may possess a general CNS-depressant effect, patients should be cautioned about combined effects with alcohol and other CNS depressants.
See WARNINGS and PRECAUTIONS for interaction with CNS drugs and alcohol.
Methocarbamol may inhibit the effect of pyridostigmine bromide. Therefore, Methocarbamol should be used with caution in patients with myasthenia gravis receiving anticholinesterase agents.
Drug /Laboratory Test Interactions:
Methocarbamol may cause a color interference in certain screening tests for 5-hydroxyindoleacetic acid using nitrosonaphthol reagent and in screening tests for urinary vanillylmandelic acid (VMA) using the Gitlow method.
Carcinogenesis, Mutagenesis, Impairment of Fertility :
Long-term studies to evaluate the carcinogenic potential of Methocarbamol have not been performed. No studies have been conducted to assess the effect of Methocarbamol on mutagenesis or its potential to impair fertility.
Pregnancy Category C
Animal reproduction studies have not been conducted with Methocarbamol. It is also not known whether Methocarbamol can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Methocarbamol Tablets should be given to a pregnant woman only if clearly needed.
Safe use of Methocarbamol Tablets has not been established with regard to possible adverse effects upon fetal development. There have been reports of fetal and congential abnormalities following in utero exposure to Methocarbamol. Therefore, Methocarbamol Tablets should not be used in women who are or may become pregnant and particularly during early pregnancy unless in the judgment of the physician the potential benefits outweigh the possible hazards.
Methocarbamol and/or its metabolites are excreted in the milk of dogs; however, it is not known whether Methocarbamol or its metabolites are excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when Methocarbamol Tablets are administered to a nursing woman.
Safety and effectiveness of Methocarbamol Tablets in pediatric patients below the age of 16 have not been established.
Adverse reactions reported coincident with the administration of Methocarbamol include:
Body as a Whole : Anaphylactic reaction, angioneurotic edema, fever, headache
Car d iovascular System : Bradycardia, flushing, hypotension, syncope, thrombophlebitis
Digestive System : Dyspepsia, jaundice (including cholestatic jaundice), nausea and vomiting
Hemic and Lymphatic S ystem : Leukopenia
Immune System : Hypersensitivity reactions
Nervous System : Amnesia, confusion, diplopia, dizziness or lightheadedness, drowsiness, insomnia, mild muscular incoordination, nystagmus, sedation, seizures (including grand mal), vertigo
Skin and Special Senses : Blurred vision, conjunctivitis, nasal congestion, metallic taste, pruritus, rash, urticaria
To report SUSPECTED ADVERSE REACTIONS, contact West-ward Pharmaceutical Corp. at 1-877-233-2001, or the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
Limited information is available on the acute toxicity of Methocarbamol. Overdose of Methocarbamol is frequently in conjunction with alcohol or other CNS depressants and includes the following symptoms: nausea, drowsiness, blurred vision, hypotension, seizures, and coma.
In post-marketing experience, deaths have been reported with an overdose of Methocarbamol alone or in the presence of other CNS depressants, alcohol or psychotropic drugs.
Management of overdose includes symptomatic and supportive treatment. Supportive measures include maintenance of an adequate airway, monitoring urinary output and vital signs, and administration of intravenous fluids if necessary. The usefulness of hemodialysis in managing overdose is unknown.
DOSAGE AND ADMINISTRATION:
500 mg – Adults: Initial dosage, 3 tablets q.i.d.; maintenance dosage, 2 tablets q.i.d.
750 mg – Adults: Initial dosage, 2 tablets q.i.d.; maintenance dosage, 1 tablet q.4h. or 2 tablets t.i.d.
Six grams a day are recommended for the first 48 to 72 hours of treatment. (For severe conditions 8 grams a day may be administered.) Thereafter, the dosage can usually be reduced to approximately 4 grams a day.
Methocarbamol Tablets 500 mg: White, Round Tablets; Debossed “West-ward 290” on one side and Scored on the other side.
Bottles of 100 tablets
Bottles of 500 tablets
Bottles of 1000 tablets
Unit Dose Box of 100 tablets
Methocarbamol Tablets 750 mg: White, Capsule Shaped Tablets; Debossed “WEST-WARD 292” on one side and Scored on the other side.
Bottles of 100 tablets
Bottles of 500 tablets
Bottles of 1000 tablets
Unit Dose Box of 100 tablets
Store at 20-25oC (68-77oF). Protect from light and moisture.
Dispense in a tight, light-resistant container as defined in the USP using a child-resistant closure.
West-ward Pharmaceutical Corp.
Eatontown, NJ 07724
Revised March 2011
Methocarbamol pharmaceutical active ingredients containing related brand and generic drugs:
Active ingredient is the part of the drug or medicine which is biologically active. This portion of the drug is responsible for the main action of the drug which is intended to cure or reduce the symptom or disease. The other portions of the drug which are inactive are called excipients; there role is to act as vehicle or binder. In contrast to active ingredient, the inactive ingredient's role is not significant in the cure or treatment of the disease. There can be one or more active ingredients in a drug.
Methocarbamol available forms, composition, doses:
Form of the medicine is the form in which the medicine is marketed in the market, for example, a medicine X can be in the form of capsule or the form of chewable tablet or the form of tablet. Sometimes same medicine can be available as injection form. Each medicine cannot be in all forms but can be marketed in 1, 2, or 3 forms which the pharmaceutical company decided based on various background research results.
Composition is the list of ingredients which combinedly form a medicine. Both active ingredients and inactive ingredients form the composition. The active ingredient gives the desired therapeutic effect whereas the inactive ingredient helps in making the medicine stable.
Doses are various strengths of the medicine like 10mg, 20mg, 30mg and so on. Each medicine comes in various doses which is decided by the manufacturer, that is, pharmaceutical company. The dose is decided on the severity of the symptom or disease.
Methocarbamol destination | category:
Destination is defined as the organism to which the drug or medicine is targeted. For most of the drugs what we discuss, human is the drug destination.
Drug category can be defined as major classification of the drug. For example, an antihistaminic or an antipyretic or anti anginal or pain killer, anti-inflammatory or so.
Methocarbamol Anatomical Therapeutic Chemical codes:
A medicine is classified depending on the organ or system it acts [Anatomical], based on what result it gives on what disease, symptom [Therapeutical], based on chemical composition [Chemical]. It is called as ATC code. The code is based on Active ingredients of the medicine. A medicine can have different codes as sometimes it acts on different organs for different indications. Same way, different brands with same active ingredients and same indications can have same ATC code.
Methocarbamol pharmaceutical companies:
Pharmaceutical companies are drug manufacturing companies that help in complete development of the drug from the background research to formation, clinical trials, release of the drug into the market and marketing of the drug.
Researchers are the persons who are responsible for the scientific research and is responsible for all the background clinical trials that resulted in the development of the drug.
Frequently asked QuestionsCan i drive or operate heavy machine after consuming Methocarbamol?
Depending on the reaction of the Methocarbamol after taken, if you are feeling dizziness, drowsiness or any weakness as a reaction on your body, Then consider Methocarbamol not safe to drive or operate heavy machine after consumption. Meaning that, do not drive or operate heavy duty machines after taking the capsule if the capsule has a strange reaction on your body like dizziness, drowsiness. As prescribed by a pharmacist, it is dangerous to take alcohol while taking medicines as it exposed patients to drowsiness and health risk. Please take note of such effect most especially when taking Primosa capsule. It's advisable to consult your doctor on time for a proper recommendation and medical consultations.Is Methocarbamol addictive or habit forming?
Medicines are not designed with the mind of creating an addiction or abuse on the health of the users. Addictive Medicine is categorically called Controlled substances by the government. For instance, Schedule H or X in India and schedule II-V in the US are controlled substances.
Please consult the medicine instruction manual on how to use and ensure it is not a controlled substance.In conclusion, self medication is a killer to your health. Consult your doctor for a proper prescription, recommendation, and guidiance.
ReviewsDrugs.com conducted a study on Methocarbamol, and the result of the survey is set out below. It is noteworthy that the product of the survey is based on the perception and impressions of the visitors of the website as well as the views of Methocarbamol consumers. We, as a result of this, advice that you do not base your therapeutic or medical decisions on this result, but rather consult your certified medical experts for their recommendations.
Two visitors reported dosesWhat is the dose of Methocarbamol drug you are taking?
According to the survey conducted among sDrugs.com website users, the maximum number of people are using the following dose 201-500mg. Few medications come in only one or two doses. Few are specific for adult dose and child dose. The dose of the medicine given to the patient depends on the severity of the symptom/disease. There can be dose adjustments made by the doctor, based on the progression of the disease. Follow-up is important.
One visitor reported time for resultsWhat is the time duration Methocarbamol drug must be taken for it to be effective or for it to reduce the symptoms?
Most chronic conditions need at least some time so the dose and the drug action gets adjusted to the body to get the desired effect. The stastistics say sDrugs.com website users needed 3 days to notice the result from using Methocarbamol drug. The time needed to show improvement in health condition after using the medicine Methocarbamol need not be same for all the users. It varies based on other factors.
Two visitors reported age
The information was verified by Dr. Arunabha Ray, MD Pharmacology