NAFCILLIN SODIUM- nafcillin sodium injection, powder, for solution 

(Store below 30°C (86°F), protected from light.)
 
For Intravenous Injection Only
To reduce the development of drug-resistant bacteria and maintain the effectiveness of nafcillin for injection and other antibacterial drugs, nafcillin for injection should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.
DESCRIPTION
Nafcillin for injection is a sterile semisynthetic penicillin derived from the penicillin nucleus 6-aminopenicillanic acid. The chemical name of nafcillin sodium is Monosodium (2S,5R,6R)-6-(2-ethoxy- 1-naphthamido)-3,3 dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylate monohydrate. It is resistant to inactivation by the enzyme penicillinase (beta-lactamase).
Nafcillin for injection intended for intravenous administration only, contain nafcillin sodium as a sterile white to slightly yellowish powder for reconstitution. The pH of the reconstituted solution is 6 to 8.5. Nafcillin for injection contains nafcillin sodium as the monohydrate equivalent to 1 gram of nafcillin per vial and is buffered with approximately 40 mg sodium citrate per gram of nafcillin. The sodium content is 66.1 mg [2.9 mEq] for the 1 g vial.
INDICATIONS AND USAGE
Nafcillin is indicated in the treatment of infections caused by penicillinase-producing staphylococci which have demonstrated susceptibility to the drug. Culture and susceptibility tests should be performed initially to determine the causative organism and its susceptibility to the drug.
Nafcillin should not be used in infections caused by organisms susceptible to penicillin G. If the susceptibility tests indicate that the infection is due to methicillin-resistant Staphylococcus sp., therapy with nafcillin for injection should be discontinued and alternative therapy provided.
To reduce the development of drug-resistant bacteria and maintain the effectiveness of nafcillin for injection and other antibacterial drugs, nafcillin for injection should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.
Information for Patients
Patients should be counseled that antibacterial drugs including nafcillin for injection should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When nafcillin for injection is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by Nafcillin for Injection or other antibacterial drugs in the future.
Diarrhea is a common problem caused by antibiotics which usually ends when the antibiotic is discontinued. Sometimes after starting treatment with antibiotics, patients can develop watery and bloody stools (with or without stomach cramps and fever) even as late as two or more months after having taken the last dose of the antibiotic. If this occurs, patients should contact their physician as soon as possible.
DOSAGE AND ADMINISTRATION
Nafcillin for injection is to be administered intravenously.
The usual intravenous dosage for adults is 500 mg every 4 hours. For severe infections, 1 gram every 4 hours is recommended. Administer slowly over at least 30 to 60 minutes to minimize the risk of vein irritation and extravasation.
Bacteriologic studies to determine the causative organisms and their susceptibility to nafcillin should always be performed. Duration of therapy varies with the type and severity of infection as well as the overall condition of the patient; therefore, it should be determined by the clinical and bacteriological response of the patient. In severe staphylococcal infections, therapy with nafcillin should be continued for at least 14 days. The treatment of endocarditis and osteomyelitis may require a longer duration of therapy.
No dosage alterations are necessary for patients with renal dysfunction, including those on hemodialysis. Hemodialysis does not accelerate nafcillin clearance from the blood.
With intravenous administration, particularly in elderly patients, care should be taken because of the possibility of thrombophlebitis.
Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever solution and container permit.
Do not add supplementary medication to nafcillin.