DOSAGE AND ADMINISTRATION
Infusion-related events are related to both the concentration and the rate of administration of vancomycin. Concentrations of no more than 5 mg/mL and rates of no more than 10 mg/min are recommended in adults (see also age-specific recommendations). In selected patients in need of fluid restriction, a concentration up to 10 mg/mL may be used; use of such higher concentrations may increase the risk of infusion-related events. An infusion rate of 10 mg/min or less is associated with fewer infusion-related events (see ADVERSE REACTIONS). Infusion-related events may occur, however, at any rate or concentration.
The use of ADD-Vantage vials of vancomycin hydrochloride is indicated only when doses of 500 mg, 750 mg or 1 g are appropriate. Patient factors, such as renal function and age, are critical in calculating correct dosage regimens (see below). If doses of 500 mg, 750 mg or 1 g are determined to be inappropriate, conventional vials of vancomycin hydrochloride should be used. ADD-VANTAGE VIALS OF VANCOMYCIN HYDROCHLORIDE SHOULD NOT BE USED IN NEONATES, INFANTS, OR PEDIATRIC PATIENTS WHO REQUIRE DOSES OF LESS THAN 500 MG.
Patients with Normal Renal Function
The usual daily intravenous dose is 2 g divided either as 500 mg every 6 hours or 1 g every 12 hours. Each dose should be administered at no more than 10 mg/min or over a period of at least 60 minutes, whichever is longer. Other patient factors, such as age or obesity, may call for modification of the usual intravenous daily dose.
The usual intravenous dosage of vancomycin is 10 mg/kg per dose given every 6 hours. Each dose should be administered over a period of at least 60 minutes. Close monitoring of serum concentrations of vancomycin may be warranted in these patients.
In pediatric patients up to the age of 1 month, the total daily intravenous dosage may be lower. In neonates, an initial dose of 15 mg/kg is suggested, followed by 10 mg/kg every 12 hours for neonates in the 1st week of life and every 8 hours thereafter up to the age of 1 month. Each dose should be administered over 60 minutes. In premature infants, vancomycin clearance decreases as postconceptional age decreases. Therefore, longer dosing intervals may be necessary in premature infants. Close monitoring of serum concentrations of vancomycin is recommended in these patients.
Patients with Impaired Renal Function and Elderly Patients
Dosage adjustment must be made in patients with impaired renal function. In premature infants and the elderly, greater dosage reductions than expected may be necessary because of decreased renal function. Measurement of vancomycin serum concentrations can be helpful in optimizing therapy, especially in seriously ill patients with changing renal function. Vancomycin serum concentrations can be determined by use of microbiologic assay, radioimmunoassay, fluorescence polarization immunoassay, fluorescence immunoassay, or high-pressure liquid chromatography. If creatinine clearance can be measured or estimated accurately, the dosage for most patients with renal impairment can be calculated using the following table. The dosage of vancomycin hydrochloride for injection per day in mg is about 15 times the glomerular filtration rate in mL/min (see following table).
The initial dose should be no less than 15 mg/kg, even in patients with mild to moderate renal insufficiency. The table is not valid for functionally anephric patients. For such patients, an initial dose of 15 mg/kg of body weight should be given to achieve prompt therapeutic serum concentrations. The dose required to maintain stable concentrations is 1.9 mg/kg/24 h. In patients with marked renal impairment, it may be more convenient to give maintenance doses of 250 to 1,000 mg once every several days rather than administering the drug on a daily basis. In anuria, a dose of 1,000 mg every 7 to 10 days has been recommended. When only serum creatinine is known, the following formula (based on sex, weight, and age of the patient) may be used to calculate creatinine clearance. Calculated creatinine clearances (mL/min) are only estimates. The creatinine clearance should be measured promptly.
|Men:||[Weight (kg) × (140 – age in years)]|
|72 × serum creatinine concentration (mg/dL)|
|Women:||0.85 × above value|
The serum creatinine must represent a steady state of renal function. Otherwise, the estimated value for creatinine clearance is not valid. Such a calculated clearance is an overestimate of actual clearance in patients with conditions: (1) characterized by decreasing renal function, such as shock, severe heart failure, or oliguria; (2) in which a normal relationship between muscle mass and total body weight is not present, such as in obese patients or those with liver disease, edema, or ascites; and (3) accompanied by debilitation, malnutrition, or inactivity. The safety and efficacy of vancomycin administration by the intrathecal (intralumbar or intraventricular) routes have not been established. Intermittent infusion is the recommended method of administration.
Preparation and Stability
Vancomycin Hydrochloride ADD-Vantage vials should be used only with approved diluents (5% dextrose injection or 0.9% sodium chloride injection) (see INSTRUCTIONS FOR USE).
It has been shown that after reconstitution, the admixture solution prepared in either dextrose injection or sodium chloride injection may be stored for 24 hours at room temperature or in a refrigerator for 14 days without significant loss of potency. However, this information is not intended to suggest that it is acceptable practice to administer such an admixture well after the time of preparation. Admixtures should be prepared as close to the time of administration as is reasonable.
Intermittent infusion is the recommended method of administration.
The 500 mg ADD-Vantage vial should be joined with at least a 100 mL ADD-Vantage flexible diluent container, the 750 mg and the 1 g ADD-Vantage vial should be joined only to a 250 mL ADD-Vantage flexible diluent container. The desired dose diluted in this manner should be administered by intravenous infusion over a period of at least 60 minutes.
Compatibility with Intravenous Fluids
Solutions that are diluted with 5% Dextrose Injection or 0.9% Sodium Chloride Injection may be stored in a refrigerator for 14 days without significant loss of potency.
Vancomycin solution has a low pH and may cause physical instability when it is mixed with other compounds.
Mixtures of solutions of vancomycin and beta-lactam antibiotics have been shown to be physically incompatible. The likelihood of precipitation increases with higher concentrations of vancomycin. It is recommended to adequately flush the intravenous lines between the administration of these antibiotics. It is also recommended to dilute solutions of vancomycin to 5 mg/mL or less.
Although intravitreal injection is not an approved route of administration for vancomycin, precipitation has been reported after intravitreal injection of vancomycin and ceftazidime for endophthalmitis using different syringes and needles. The precipitates dissolved gradually, with complete clearing of the vitreous cavity over two months and with improvement of visual acuity.
Parenteral drug products should be visually inspected for particulate matter and discoloration prior to administration, whenever solution or container permits.
For Oral Administration
NOTE: For information only. ADD-Vantage Vials cannot be used to supply vancomycin for this purpose.
Oral vancomycin is used in treating antibiotic-associated pseudomembranous colitis caused by C. difficile and for staphylococcal enterocolitis. Vancomycin is not effective by the oral route for other types of infections. The usual adult total daily dosage is 500 mg to 2 g given in 3 or 4 divided doses for 7 to 10 days. The total daily dose in children is 40 mg/kg of body weight in 3 or 4 divided doses for 7 to 10 days. The total daily dosage should not exceed 2 g. The appropriate dose may be diluted in 1 oz of water and given to the patients to drink. Common flavoring syrups may be added to the solution to improve the taste for oral administration. The diluted solution may be administered via a nasogastric tube.