ROBAXIN- methocarbamol injection
West-ward Pharmaceutical Corp.
Rx only
DESCRIPTION
ROBAXIN (methocarbamol injection, USP) Injectable, a carbamate derivative of guaifenesin, is a central nervous system (CNS) depressant with sedative and musculoskeletal relaxant properties. It is a sterile, pyrogen-free solution intended for intramuscular or intravenous administration.
Each mL contains: methocarbamol, USP 100 mg, polyethylene glycol 300, NF 0.5 mL, Water for Injection, USP q.s. The pH is adjusted, when necessary, with hydrochloric acid and/or sodium hydroxide. The chemical name of methocarbamol is 3?(2?methoxyphenoxy)?1,2-propanediol 1?carbamate and has the empirical formula of C11 H15 NO5 . 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.
ROBAXIN Injectable has a pH between 3.5 and 6.0.
AFTER MIXING WITH I.V. INFUSION FLUIDS, DO NOT REFRIGERATE.
CLINICAL PHARMACOLOGY
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.
INDICATIONS AND USAGE
The injectable form of methocarbamol 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. Methocarbamol does not directly relax tense skeletal muscles in man.
