Nafcillin dosing

Nafci 11 i n/oxaci 11 f n 75 mg/kg IV per day in divided doses every 8-12 hours Nafcillin 100-150 mg/kg IV per day in divided doses every 6-8 hours Oxacillin 150-200 mg/kg IV per day in divided doses every 6-8 hours 200 mg/kg IV per day in divided doses every 6 hours max, 2 gm pediatrics greater than 3 months of age... 

Nafcillin or oxacillin 12 g/24 hours IV in 4-6 equally divided doses 6 IA For complicated right-sided IE and for left-sided IE, 6-week treatment for uncomplicated rightsided IE, 2-week treatment... 

Penicillin C 24 million units/24 hours IV in 4 to 6 equally divided doses may be used in place of nafcillin or oxacillin if strain is penicillin-susceptible (minimum inhibitory concentration less than or equal to 0.1 mcg/mL) and does not produce P-lactamase. cGentamicin should be administered in close temporal proximity to vancomycin, nafcillin, or oxacillin dosing. 

Pediatric dosec nafcillin Table 71-3 for dosing guidelines) ... 

Gentamicin should be administered in close proximity to vancomycin, nafcillin, or oxacillin dosing. cPediatric dose should not exceed that of a normal adult. 

Nafcillin or oxacillin6 12 gf24 hours IV in four to six equally divided doses 6 weeks IA For complicated right-sided infective endocarditis and for left-sided... 

Aminoglycosidee + penicillin G 100,000-200,000 unit kg/day IV in four divided doses or a semisynthetic penicillin (nafcillin 150-200 mg/kg/day [not to exceed 12 g/24 hours] IV in four to six equally divided doses) depending on isolation of staphylococci or streptococa ... 

For parenteral therapy, nafciUin and oxacillin offer comparable efficacy and antimicrobial spectra of activity. Although both drugs undergo hepatic metabolism, only nafcillin requires dose adjustment in patients with combined hepatic and renal insufficiency. Other pharmacokinetic data for nafcillin and oxacillin appear in Table 45.1. Indications for nafcillin or oxacillin include severe staphylococcal infections like cellulitis, empyema, endocarditis, osteomyelitis, pneumonia, septic arthritis, and toxic shock syndrome. 

Nafcillin is primarily cleared by biliary excretion. Oxacillin, dicloxacillin, and cloxacillin are eliminated by both the kidney and biliary excretion no dosage adjustment is required for these drugs in renal failure. Because clearance of penicillins is less efficient in the newborn, doses adjusted for weight alone result in higher systemic concentrations for longer periods than in the adult. 

In dogs, absorption following oral administration tends to be poor. At similar oral doses, peak serum levels are lower and plasma levels are less persistent than those observed for methicillin. Following intramuscular administration, however, maximum concentrations in serum are reached within 30 min. In contrast to methicillin, liver is the main excretory pathway for nafcillin. Like most other penicillins, nafcillin undergoes biotransformation to a small extent. Parent compound and its metabolites are excreted in bile and urine. Concentrations of nafcillin in tissues tend to be higher and more persistent following parenteral administration than was the case for methicillin, obviously due to enterohepatic recirculation. 

Nafcillin or oxacillin 150-200 mg/kg/day (not to exceed 12 24 hours) IV in four to six equally divided doses ... 

A patient experienced the effects of interactions of warfarin with nafcillin and dicloxacillin (333). During co-administration of nafcillin, warfarin doses were increased to as much as 4.5 times the previous amounts needed to provide adequate anticoagulation. During co-administration of dicloxacillin, warfarin doses gradually fell, but still stabilized at a higher maintenance dose than before. 

In a 71-year-old woman with pneumonia, vesicles and bullae developed on the eighth day of antibiotic therapy that consisted of one dose of intravenous vancomycin followed by a course of nafcillin (73). 

Nafcillin 1-2g IVq.4hr 35% No renal adjustment is required None None Dose for GFR 10-50 ml/min... 

Nafcillin is primarily cleared by biliary excretion while dicloxacillin is eliminated by both kidney and biliary excretion. No dose adjustments are needed in the setting of renal or hepatic dysfunction. 

Adverse reactions Overall, the penicillins are well tolerated. The most common adverse effects are due to hypersensitivity reactions. Hypersensitivity reactions can be simply categorized as immediate reactions (type 1) or late reactions. Type 1 reactions are IgE mediated and are often associated with systemic manifestations such as diffuse erythema, pruritus, urticaria, angioedema, and bronchospasm. The most severe yet rare IgE-mediated side effect is anaphylaxis (0.05%). Type 1 reactions usually occur within 72 hr of administration. Late reactions usually occur 72 hr after drug administration. The most common late reactions include skin rashes characterized as maculopapular or morbilliform rashes. Rarely, nafcillin may cause neutropenia. Seizures in high doses, vaginal moniliasis, and Clostridium difficile infection also can occur with all penicillins... 

TM is given a single dose of vancomycin. Ten minutes into the infusion, TM s blood pressure suddenly drops to 80/60 mm Hg, and he feels "hot and flushed." What is the best course of action for TM s "red man syndrome" A Discontinue the infusion, start nafcillin. 

It is incumbent on health professionals to avoid toxic drugs whenever possible. Antibiotics associated with CNS toxicities, usually when not dose-adjusted for renal function, include penicillins, cephalosporins, quinolones, and imipenem. Hematologic toxicities generally are manifested with prolonged use of nafcillin (neutropenia), piperacillin (platelet dysfunction), cefotetan (hypoprothrombinemia), chloramphenicol (bone marrow suppression, both idiosyncratic and dose-related toxicity), and trimethoprim (megaloblastic anemia). Reversible nephrotoxicity classically is associated with aminoglycosides... 

Since staphylococcal and streptococcal cellulitis are indistinguishable clinically," administration of a semisynthetic penicillin (nafcillin or oxacillin) is recommended until a definitive diagnosis, by skin or blood cultures, can be made " " (Table 108-3). Mild to moderate infections not associated with systemic symptoms may be treated orally with dicloxacillin. If documented to be a mild cellulitis secondary to streptococci, oral penicillin VK or intramuscular procaine penicillin may be administered. More severe infections, either staphylococcal or streptococcal, should be treated initially with intravenous antibiotic regimens. Ceftriaxone 50-100 mg/kg as a single daily dose is efficacious in the treatment of celluMs in pediatric patients. The usual duration of therapy for cellulitis is 7 to 10 days. " ... 

Most are eliminated via active tubular secretion with half-life <60 min. Dose reduction needed only in major renal dysfunction. Nafcillin and oxacillin eliminated largely in bile ampicillin undergoes enterohepatic cycling, but is excreted by the kidney. Benzathine penicillin G—repository form (half-life of 2 weeks). 

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