Rx Only

Methocarbamol Tablets, USP, a carbamate derivative of guaifenesin, is a central nervous system (CNS) depressant with sedative and musculoskeletal relaxant properties.

The chemical name of methocarbamol is 3-(2-methoxyphenoxy)-1,2-propanediol 1-carbamate and has the empirical formula C11H15NO5. Its molecular weight is 241.24. The structural formula is shown below.

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.

Methocarbamol Tablets, USP 500 mg are available as a white, round, scored, film-coated tablet containing 500 mg of methocarbamol, USP for oral administration. The inactive ingredients present are microcrystalline cellulose, croscarmellose sodium, povidone (k-30), sodium lauryl sulfate, colloidal silicon dioxide, magnesium stearate, hypromellose, titanium dioxide, polyethylene glycol, polysorbate 80.

Methocarbamol Tablets, USP 750 mg are available as a white, capsule-shaped, film-coated tablet containing 750 mg of methocarbamol, USP for oral administration. The inactive ingredients present are microcrystalline cellulose, croscarmellose sodium, povidone (k-30), sodium lauryl sulfate, colloidal silicon dioxide, magnesium stearate, hypromellose, titanium dioxide, polyethylene glycol, polysorbate 80.

The mechanism of action of methocarbamol in humans has not been established, but may be due to general CNS depression. It has no direct action on the contractile mechanism of striated muscle, the motor end plate or the nerve fiber.

Methocarbamol Tablets, USP 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, USP 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, USP should be cautioned about combined effects with alcohol and other CNS depressants.

Safe use of Methocarbamol Tablets, USP has not been established with regard to possible adverse effects upon fetal development. There have been reports of fetal and congenital abnormalities following in uteroexposure to methocarbamol. Therefore, Methocarbamol Tablets, USP 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 (see PRECAUTIONS, Pregnancy).

Adverse reactions reported coincident with the administration of methocarbamol include:

Body as a whole:Anaphylactic reaction, angioneurotic edema, fever, headache

Cardiovascular system:Bradycardia, flushing, hypotension, syncope, thrombophlebitis

Digestive system:Dyspepsia, jaundice (including cholestatic jaundice), nausea and vomiting

Hemic and lymphatic system: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

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.

Methocarbamol Tablets, USP, 500 mg – Adults:
Initial dosage: 3 tablets four times daily
Maintenance dosage: 2 tablets four times daily

Methocarbamol Tablets, USP, 750 mg – Adults:
Initial dosage: 2 tablets four times daily
Maintenance dosage: 1 tablet every 4 hours or 2 tablets three times daily

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, USP, 500 mg tablets are white, round, film-coated tablets, debossed "G173" on one side, plain and scored on the other side. They are supplied as follows:

Bottles of 60 NDC 72789-481-60

Bottles of 90 NDC 72789-481-90

Bottles of 100 NDC 72789-481-01

Bottles of 180 NDC 72789-481-93

Bottles of 500 NDC 72789-481-82

Bottles of 1000 NDC 72789-481-95

Methocarbamol

500 mg

Rx Only

Film-Coated Tablets