Results for Vial

VANCOMYCIN (Vancomycin Hydrochloride)

08:18
 VANCOMYCIN (Vancomycin Hydrochloride)

VANCOMYCIN (Vancomycin Hydrochloride)
VANCOMYCIN (Vancomycin Hydrochloride)
VANCOMYCIN (Vancomycin Hydrochloride)

DESCRIPTION
Vancomycin is ABBOTTs brand name for Vancomycin HCI Injection for I.V. use.
Vancomycin Hydrochloride has the chemical formula C H Cl N O . HCL. The 66 75 2 8 24 
formula weightis1.486:500 mg ofthe base is equivalentto0.34mmol and 1 g ofthe base
isequivalentto0.67mmol.

COMPOSITION
EachvialofVancomycininjection contains:
(1) VancomycinHCI equivalantto, 
Vancomycin................. 500 mg
(2) VancomycinHCI equivalentto, 
Vancomycin......... 1000mg
CLINICAL PHARMACOLOGY: Vancomycin Hydrochloride is poorly absorbed after 
oral administration: It is given intravenously for therapy of systemic injections. 
Intramuscular injection ispainful.
In subjects with normal kidney function, multiple intravenous dosing of1g ofVancomycin
(15 mg/kg) infused over 60 minutes produces mean plasma concentrations of
approximately 63 mg/L immediately at the completion of infusion, mean plasma
concentrations of approximately 23mg/L 2 hours after infusion, and mean plasma
concentrations of approximately 8 mg/L 11 hours after the end of the infusion. Multiple 
dosingof500 mginfused over30minutes producesmeanplasmaconcentrationsofabout 49 mg/L at the completion of infusion, mean plasma concentrations of about 19 mg/L 2hours after infusion, and mean plasma concentrations of about 10 mg/L 6 hours after infusion. The plasma concentrations during multiple dosing are similar to those after a singledose.
The mean elimination half-life ofVancomycin fromplasma is4 to 6 hours in subjects with normal renal functions. In the first 24 hours, about 75% of an administered dose of Vancomycin is excreted in urine by glomerularfiltration. Mean plasma clearance is about 
0.058 L/kg/hr and mean renal clearance is about 0.048 L/kg/hr.Renal dysfunction slows excretion of Vancomycin. In anephric patients, the average half-life of elimination is 7.5days. The distributioncoefficient isfrom0.3 - 0.43L/kg. There isnoapparentmetabolism
of a drug. About 60 percent of an intraperitoneal dose of vancomycin Hydrochloride administered during peritoneal dialysis is absorbed systematically in 6 hours, Serum 
concentrations of about 10mg/L are achieved by intraperitoneal injection of 30mg/kg of Vancomycin. Vancomycin is not effectively removed by either hemodialysis or peritoneal dialysis, there havebeennoreports ofVancomycinclearance withhemoperfusion.
Total systematicand renal clearance ofVancomycinmay bereduced inthe elderly.
Vancomycin is approximately 55% serum protein bound as measured by ultrafiltration at
Vancomycinserum concentrationsof10-100mg/L. After IVpericardial administrationof
Vancomycin Hcl, inhibitory concentrations are present in pleural, pericardial, ascitic, and synovial fluids; in urine: in peritoneal dialysis fluid; and in atrial appendage tissue. 
VancomycinHCI dosenot readily diffuse acrossnormalmeningesintothe spinalfluid,but.
whenthe meningesare inflamed, penetration intothe spinalfluid occurs.
VANCOMYCIN (Vancomycin Hydrochloride) VANCOMYCIN (Vancomycin Hydrochloride) Reviewed by Athar on 08:18 Rating: 5

ACYCLOVIR (Acyclovir Sodium)

02:54
       ACYCLOVIR (Acyclovir Sodium)
ACYCLOVIR (Acyclovir Sodium)
ACYCLOVIR (Acyclovir Sodium)

ACYCLOVIR (Acyclovir Sodium)


DESCRIPTION

Acyclovir is a synthetic nucleoside analog active against herpes viruses. Acyclovir sodium sterile powder for 
solution for injection is a formulation for intravenous administration.
The chemical name of acyclovir sodium is 2-amino-1, 9-dihydro-9-[(2-hydroxyethoxy) methyl] - 6H - purin - 6 
- one monosodium salt. 
Acyclovir sodium is a white to off-white, crystalline powder with a molecular weight of 247 daltons, and a 
solubility in water at 25° C exceeding 100 mg/mL. Each 250 mg of acyclovir sodium sterile powder for solution 
for injection when reconstituted with 10 mL of sterile diluent yields 25 mg/mL. Each 500 mg or 1 g vial of 
acyclovir sodium sterile powder for solution for injection when reconstituted with 10 mL or 20 mL, respectively, 
sterile diluent yields 50 mg/mL acyclovir (pH approximately 11). Further dilution in any appropriate intravenous 
solution must be performed before infusion (see DOSAGE AND ADMINISTRATION: Method of Preparation and Administration). At physiologic pH, acyclovir exists as the un-ionized form with a molecular weight of 225 
daltons and a maximum solubility of 2.5 mg/mL in water at 37° C. May contain sodium hydroxide for pH 
adjustment. Acyclovir sodium sterile powder for solution for injection is prepared as a solution and lyophilized in 
its final container. For each 250 mg of acyclovir, the sodium content is approximately 26 mg (1.1 mEq); for each 
500 mg of acyclovir, the sodium content is approximately 52 mg (2.2 mEq).

VIROLOGY
Mechanism of Antiviral Action
Acyclovir is a synthetic purine nucleoside analogue with in vitro and in vivo inhibitory activity against herpes 
simplex virus types 1 (HSV-1), 2 (HSV-2), and varicella-zoster virus (VZV). In cell culture, acyclovir's highest 
antiviral activity is against HSV-1, followed in decreasing order of potency against HSV-2 and VZV.
The inhibitory activity of acyclovir is highly selective due to its affinity for the enzyme thymidinen kinase (TK) 
encoded by HSV and VZV. This viral enzyme converts acyclovir into acyclovir monophosphate, a nucleotide 
analogue. The monophosphate is further converted into diphosphate by cellular guanylate kinase and into 
triphosphate by a number of cellular enzymes. In vitro, acyclovir triphosphate stops replication of herpes viral 
DNA. This is accomplished in three ways: 1) competitive inhibition of viral DNA polymerase, 2) incorporation 
into and termination of the growing viral DNA chain, and 3) inactivation of the viral DNA polymerase. The 
greater antiviral activity of acyclovir against HSV compared to VZV is due to its more efficient phosphorylation 
by the viral TK.

Antiviral Activities
The quantitative relationship between the in vitro susceptibility of herpes viruses to antivirals and the clinical 
response to therapy has not been established in humans, and virus sensitivity testing has not been standardized. 
Sensitivity testing results, expressed as the concentration of drug required to inhibit by 50% the growth of virus in 
cell culture (IC50), vary greatly depending upon a number of factors.
Using plaque-reduction assays, the IC50 against herpes simplex virus isolates ranges from 0.02 to 13.5 mcg/mL 
for HSV-1 and from 0.01 to 9.9 mcg/mL for HSV-2. The IC50 for acyclovir against most laboratory strains and 
clinical isolates of VZV ranges from 0.12 to 10.8 mcg/mL. Acyclovir also demonstrates activity against the Oka 
vaccine strain of VZV with a mean IC50 for 1.35 mcg/mL. 

Drug Resistance
Resistance of HSV and VZV to antiviral nucleoside analogues can result from qualitative or quantitative changes 
in the viral TK or DNA polymerase. Clinical isolates of HSV and VZV with reduced susceptibility to acyclovir have 
been recovered from immunocompromised patients, especially with advanced HIV infection. While most of the 
acyclovir-resistant mutants isolated thus far from such patients have been found to be TK-deficient mutants, 
other mutants involving the viral TK gene (TK partial and TK altered) and DNA polymerase have been isolated. 
TK-negative mutants may cause severe disease in infants and immunocompromised adults. The possibility of viral 
resistance to acyclovir should be considered in patients who show poor clinical response during therapy.

CLINICAL PHARMACOLOGY

Pharmacokinetics
The pharmacokinetics of acyclovir after intravenous administration have been evaluated in adult patients with 
normal renal function during Phase I & II studies after single doses ranging from 0.5 to 15 mg/kg and after multiple 
doses ranging from 2.5 to 15 mg/kg every eight hours. Proportionality between dose and plasma levels is seen after 
single doses or at steady state after multiple dosing.
When acyclovir was administered to adults at 5 mg/kg (approximately 250 mg/m 2 ) by 1-hour infusions every 
eight hours, mean steady-state peak and trough concentrations of 9.8 mcg/mL (range: 5.5 to 13.8 mcg/mL) and 
0.7 mcg/mL (range: 0.2 to 1.0 mcg/mL), respectively, were achieved. At a dose of 10 mg/kg given by one-hour 
infusion every eight hours, mean steady-state peak and trough concentrations were 22.9 mcg/mL (range: 14.1 to 
44.1 mcg/mL) and 1.9 mcg/mL (range: 0.5 to 2.9 mcg/mL).

Concentrations achieved in the cerebrospinal fluid are approximately 50% of plasma values. Plasma protein 
binding is relatively low (9 to 33%) and drug interactions involving binding site displacement are not Pediatrics (under 12 years of age):10 mg/kg infused at a constant rate over at least one hour, every eight hours for seven days.

Method of Preparation
Each 10 mL vial contains acyclovir sodium equivalent to 250 mg or 500 mg of acyclovir. Each 20 mL vial contains 
acyclovir sodium equivalent to 1000 mg of acyclovir. The contents of the vial should be dissolved in sterile water 
for injection or 0.9% sodium chloride as follows:
Shake the vial well to assure complete dissolution before measuring and transferring each individual dose.
ACYCLOVIR (Acyclovir Sodium) ACYCLOVIR (Acyclovir Sodium) Reviewed by Athar on 02:54 Rating: 5
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