OXACILLIN SODIUM
For general information on the penicillins, including adverse effects, contraindications, overdosage, drug interactions and monitoring parameters, refer to the monograph: Penicillins, General Information.
Chemistry - An isoxazolyl-penicillin, oxacillin sodium is a semisynthetic penicillinase-resistantpenicillin. It is available commercially as the monohydrate sodium salt which occurs as a fine, white, crystalline powder that is odorless or has a slight odor. It is freely soluble in water and has a pKa ofabout 2.8. One mg of oxacillin sodium contains not less than 815-950 micrograms of oxacillin.
Each gram of the commercially available powder for injection contains 2.8 -3.1 mEq of sodium.
Oxacillin sodium may also be known as sodium oxacillin or methylphenyl isoxazolyl penicillin.
After reconstituting the sterile powder for injection with sterile water for injection or sterile sodiumchloride 0.9%, the resultant solution with a concentration of 167 mg/ml is stable for 3 days at roomtemperature or 7 days if refrigerated. The manufacturer recommends using different quantities ofdiluent depending on whether the drug is to be administered IM, IV directly, or IV (piggyback).
Refer to the package insert for specific instructions.
Oxacillin sodium injection is reportedly compatible with the following fluids/drugs: dextrose 5%& 10% in water, dextrose 5% & 10% in sodium chloride 0.9%, lactated Ringer's injection, sodiumchloride 0.9% amikacin sulfate, cephapirin sodium, choramphenicol sodium succinate, dopamine
HCl, potassium chloride, sodium bicarbonate and verapamil.
Oxacillin sodium injection is reportedly incompatible with the following fluids/drugs: oxytetracycline HCl and tetracycline HCl. Compatibility is dependent upon factors such as pH, concentration, temperature and diluents used. It is suggested to consult specialized references for morespecific information (e.g., Handbook on Injectable Drugs by Trissel; see bibliography).
Pharmacology/Uses, Indications - Refer to the Cloxacillin monograph and the Doses section for
Oxacillin for more information regarding this drug.
Pharmacokinetics (specific) - Oxacillin sodium is resistant to acid inactivation in the gut, but isonly partially absorbed after oral administration. The bioavailability after oral administration inhumans has been reported to range from 30-35%, and, if given with food, both the rate and extent ofabsorption is decreased. After IM administration, oxacillin is rapidly absorbed and peak levelsgenerally occur within 30 minutes.
The drug is distributed to the lungs, kidneys, bone, bile, pleural fluid, synovial fluid and ascitic fluid. The volume of distribution is reportedly 0.4 L/kg in human adults and 0.3 L/kg in dogs. As with the other penicillins, only minimal amounts are distributed into the CSF, but levels are increased with meningeal inflammation. In humans, approximately 89-94% of the drug is bound to plasma proteins.
Oxacillin is partially metabolized to both active and inactive metabolites. These metabolites and theparent compound are rapidly excreted in the urine via both glomerular filtration and tubularsecretion mechanisms. A small amount of the drug is also excreted in the feces via biliary elimination. The serum half-life in humans with normal renal function ranges from about 18-48 minutes.
In dogs, 20-30 minutes has been reported as the elimination half-life.
Chemistry - An isoxazolyl-penicillin, oxacillin sodium is a semisynthetic penicillinase-resistantpenicillin. It is available commercially as the monohydrate sodium salt which occurs as a fine, white, crystalline powder that is odorless or has a slight odor. It is freely soluble in water and has a pKa ofabout 2.8. One mg of oxacillin sodium contains not less than 815-950 micrograms of oxacillin.
Each gram of the commercially available powder for injection contains 2.8 -3.1 mEq of sodium.
Oxacillin sodium may also be known as sodium oxacillin or methylphenyl isoxazolyl penicillin.
Storage, Stability, Compatibility
Oxacillin sodium capsules, powder for oral solution, andpowder for injection should be stored at room temperature (15-30°C) in tight containers. Afterreconstituting with water, refrigerated and discard any remaining oral solution after 14 days. If keptat room temperature, the oral solution is stable for 3 days.After reconstituting the sterile powder for injection with sterile water for injection or sterile sodiumchloride 0.9%, the resultant solution with a concentration of 167 mg/ml is stable for 3 days at roomtemperature or 7 days if refrigerated. The manufacturer recommends using different quantities ofdiluent depending on whether the drug is to be administered IM, IV directly, or IV (piggyback).
Refer to the package insert for specific instructions.
Oxacillin sodium injection is reportedly compatible with the following fluids/drugs: dextrose 5%& 10% in water, dextrose 5% & 10% in sodium chloride 0.9%, lactated Ringer's injection, sodiumchloride 0.9% amikacin sulfate, cephapirin sodium, choramphenicol sodium succinate, dopamine
HCl, potassium chloride, sodium bicarbonate and verapamil.
Oxacillin sodium injection is reportedly incompatible with the following fluids/drugs: oxytetracycline HCl and tetracycline HCl. Compatibility is dependent upon factors such as pH, concentration, temperature and diluents used. It is suggested to consult specialized references for morespecific information (e.g., Handbook on Injectable Drugs by Trissel; see bibliography).
Pharmacology/Uses, Indications - Refer to the Cloxacillin monograph and the Doses section for
Oxacillin for more information regarding this drug.
Pharmacokinetics (specific) - Oxacillin sodium is resistant to acid inactivation in the gut, but isonly partially absorbed after oral administration. The bioavailability after oral administration inhumans has been reported to range from 30-35%, and, if given with food, both the rate and extent ofabsorption is decreased. After IM administration, oxacillin is rapidly absorbed and peak levelsgenerally occur within 30 minutes.
The drug is distributed to the lungs, kidneys, bone, bile, pleural fluid, synovial fluid and ascitic fluid. The volume of distribution is reportedly 0.4 L/kg in human adults and 0.3 L/kg in dogs. As with the other penicillins, only minimal amounts are distributed into the CSF, but levels are increased with meningeal inflammation. In humans, approximately 89-94% of the drug is bound to plasma proteins.
Oxacillin is partially metabolized to both active and inactive metabolites. These metabolites and theparent compound are rapidly excreted in the urine via both glomerular filtration and tubularsecretion mechanisms. A small amount of the drug is also excreted in the feces via biliary elimination. The serum half-life in humans with normal renal function ranges from about 18-48 minutes.
In dogs, 20-30 minutes has been reported as the elimination half-life.