NDC 16590-370 Acyclovir

NDC Product Code 16590-370

NDC CODE: 16590-370

Proprietary Name: Acyclovir What is the Proprietary Name?
The proprietary name also known as the trade name is the name of the product chosen by the medication labeler for marketing purposes.

Drug Use Information

Drug Use Information
The drug use information is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate. This information is not individual medical advice and does not substitute for the advice of a health care professional. Always ask a health care professional for complete information about this product and your specific health needs.

  • Acyclovir is used to treat infections caused by certain types of viruses. It treats cold sores around the mouth (caused by herpes simplex), shingles (caused by herpes zoster), and chickenpox. This medication is also used to treat outbreaks of genital herpes. In people with frequent outbreaks, acyclovir is used to help reduce the number of future episodes. Acyclovir is an antiviral drug. However, it is not a cure for these infections. The viruses that cause these infections continue to live in the body even between outbreaks. Acyclovir decreases the severity and length of these outbreaks. It helps the sores heal faster, keeps new sores from forming, and decreases pain/itching. This medication may also help reduce how long pain remains after the sores heal. In addition, in people with a weakened immune system, acyclovir can decrease the risk of the virus spreading to other parts of the body and causing serious infections.

Product Characteristics

Color(s):
WHITE (C48325)
Shape: OVAL (C48345)
CAPSULE (C48336)
Size(s):
20 MM
14 MM
Imprint(s):
RX505
RX504
Score: 1

NDC Code Structure

NDC 16590-370-30

Package Description: 30 TABLET in 1 BOTTLE

NDC 16590-370-60

Package Description: 60 TABLET in 1 BOTTLE

NDC 16590-370-90

Package Description: 90 TABLET in 1 BOTTLE

This product is EXCLUDED from the official NDC directory because the listing data was inactivated by the FDA.

NDC Product Information

Acyclovir with NDC 16590-370 is a product labeled by Stat Rx Usa. The product's dosage form is and is administered via form. The RxNorm Crosswalk for this NDC code indicates multiple RxCUI concepts are associated to this product: 197311 and 197313.

Inactive Ingredient(s)

About the Inactive Ingredient(s)
The inactive ingredients are all the component of a medicinal product OTHER than the active ingredient(s). The acronym "UNII" stands for “Unique Ingredient Identifier” and is used to identify each inactive ingredient present in a product.

  • MAGNESIUM STEARATE (UNII: 70097M6I30)
  • CELLULOSE, MICROCRYSTALLINE (UNII: OP1R32D61U)
  • MAGNESIUM STEARATE (UNII: 70097M6I30)
  • CELLULOSE, MICROCRYSTALLINE (UNII: OP1R32D61U)
  • SILICON DIOXIDE (UNII: ETJ7Z6XBU4)

Product Labeler Information

What is the Labeler Name?
Name of Company corresponding to the labeler code segment of the Product NDC.

Labeler Name: Stat Rx Usa
Labeler Code: 16590
Start Marketing Date: 09-30-1998 What is the Start Marketing Date?
This is the date that the labeler indicates was the start of its marketing of the drug product.

Listing Expiration Date: 12-31-2017 What is the Listing Expiration Date?
This is the date when the listing record will expire if not updated or certified by the product labeler.

Exclude Flag: I - INACTIVATED, the listing data was inactivated by the FDA. What is the NDC Exclude Flag?
This field indicates whether the product has been removed/excluded from the NDC Directory for failure to respond to FDA"s requests for correction to deficient or non-compliant submissions ("Y"), or because the listing certification is expired ("E"), or because the listing data was inactivated by FDA ("I"). Values = "Y", "N", "E", or "I".

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Information for Patients

Acyclovir

Acyclovir is pronounced as (ay sye' kloe veer)

Why is acyclovir medication prescribed?
Acyclovir is used to decrease pain and speed the healing of sores or blisters in people who have varicella (chickenpox)), herpes zoster (shingles; a rash that can occur i...
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Acyclovir Product Labeling Information

The product labeling information includes all published material associated to a drug. Product labeling documents include information like generic names, active ingredients, ingredient strength dosage, routes of administration, appearance, usage, warnings, inactive ingredients, etc.

Product Labeling Index

Other

Rxonly

Description

Acyclovir is a synthetic
nucleoside analogue active against herpesviruses. Acyclovir capsules, USP and
acyclovir tablets, USP are formulations for oral administration.Each capsule of
acyclovir contains 200 mg of acyclovir, USP and the inactive ingredients lactose
monohydrate, magnesium stearate, and pregelatinized starch. The capsule shell
consists of black iron oxide, edible printing ink, gelatin, and titanium
dioxide.Each 800 mg tablet of
acyclovir contains 800 mg of acyclovir, USP and the inactive ingredients
colloidal silicone dioxide, magnesium stearate, microcrystalline cellulose,
pregelatinized starch, and sodium starch glycolate.Each 400 mg tablet of
acyclovir contains 400 mg of acyclovir, USP and the inactive ingredients
colloidal silicone dioxide, magnesium stearate, microcrystalline cellulose,
pregelatinized starch, and sodium starch glycolate.Acyclovir, USP is a
white crystalline powder with the molecular formula C8H11N5O3 and a molecular weight of 225. The maximum solubility in
water at 37°C is 2.5 mg/mL.The pka’s of acyclovir
are 2.27 and 9.25. The chemical name of acyclovir is 2-amino-1,
9-dihydro-9-[(2-hydroxyethoxy)methyl]-6H-purin-6-one;
it has the following structural formula:

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). The inhibitory activity
of acyclovir is highly selective due to its affinity for the enzyme thymidine
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 3
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 of 1.35 mcg/mL.Drug
Resistance: Resistance of HSV and VZV to acyclovir can result from
qualitative and quantitative changes in the viral TK and/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
immunocompromised 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 oral administration
have been evaluated in healthy volunteers and in immunocompromised patients with
herpes simplex or varicella-zoster virus infection. Acyclovir pharmacokinetic
parameters are summarized in Table 1.Table 1: Acyclovir
Pharmacokinetic Characteristics (Range)ParameterRangePlasma protein
binding 
9% to 33%  Plasma
elimination half-life 
2.5 to 3.3 hr  Average oral
bioavailability 
10% to 20%*  *Bioavailability decreases with increasing
dose.  In one multiple-dose, cross-over study in healthy subjects (n = 23), it was
shown that increases in plasma acyclovir concentrations were less than dose
proportional with increasing dose, as shown in Table 2.
The decrease in bioavailability is a function of the dose and not the dosage
form.Table
2: Acyclovir Peak and Trough Concentrations at Steady StateParameter200 mg400 mg800 mgC ss max0.83 mcg/mL1.21 mcg/mL1.61 mcg/mLC
ss trough0.46 mcg/mL0.63 mcg/mL0.83 mcg/mLThere was no effect of
food on the absorption of acyclovir (n = 6); therefore, acyclovir capsules and
tablets may be administered with or without food.The only known urinary
metabolite is 9-[(carboxymethoxy)methyl]guanine.Special
Populations: Adults with Impaired Renal Function:
The half-life and total body clearance of acyclovir are dependent
on renal function. A dosage adjustment is recommended for patients with reduced
renal function (See DOSAGE AND ADMINISTRATION).Geriatrics: Acyclovir plasma concentrations are
higher in geriatric patients compared to younger adults, in part due to
age-related changes in renal function. Dosage reduction may be required in
geriatric patients with underlying renal impairment (See PRECAUTIONS: Geriatric Use).Pediatrics: In general, the pharmacokinetics of
acyclovir in pediatric patients is similar to that of adults. Mean half-life
after oral doses of 300 mg/m2 and 600 mg/m2 in pediatric patients aged 7 months to 7 years was 2.6 hours
(range 1.59 to 3.74 hours).Drug
Interactions: Co-administration of probenecid with intravenous acyclovir
has been shown to increase the mean acyclovir half-life and the area under the
concentration-time curve. Urinary excretion and renal clearance were
correspondingly reduced.Clinical Trials Initial Genital Herpes: Double-blind,
placebo-controlled studies have demonstrated that orally administered acyclovir
significantly reduced the duration of acute infection and duration of lesion
healing. The duration of pain and new lesion formation was decreased in some
patient groups.Recurrent Genital Herpes: Double-blind,
placebo-controlled studies in patients with frequent recurrences (6 or more
episodes per year) have shown that orally administered acyclovir given daily for
4 months to 10 years prevented or reduced the frequency and/or severity of
recurrences in greater than 95% of patients.In a study of patients
who received acyclovir 400 mg twice daily for 3 years, 45%, 52%, and 63% of
patients remained free of recurrences in the first, second, and third years,
respectively. Serial analyses of the 3-month recurrence rates for the patients
showed that 71% to 87% were recurrence free in each quarter.Herpes Zoster Infections: In a double-blind,
placebo-controlled study of immunocompetent patients with localized cutaneous
zoster infection, acyclovir (800 mg 5 times daily for 10 days) shortened the
times to lesion scabbing, healing, and complete cessation of pain, and reduced
the duration of viral shedding and the duration of new lesion formation.In a similar
double-blind, placebo-controlled study, acyclovir (800 mg 5 times daily for 7
days) shortened the times to complete lesion scabbing, healing, and cessation of
pain; reduced the duration of new lesion formation; and reduced the prevalence
of localized zoster-associated neurologic symptoms (paresthesia, dysesthesia, or
hyperesthesia).Treatment was begun
within 72 hours of rash onset and was most effective if started within the first
48 hours.Adults greater than 50
years of age showed greater benefit.Chickenpox: Three randomized, double-blind,
placebo-controlled trials were conducted in 993 pediatric patients aged 2 to 18
years with chickenpox. All patients were treated within 24 hours after the onset
of rash. In 2 trials, acyclovir was administered at 20 mg/kg 4 times daily (up
to 3,200 mg per day) for 5 days. In the third trial, doses of 10, 15, or 20
mg/kg were administered 4 times daily for 5 to 7 days. Treatment with acyclovir
shortened the time to 50% healing; reduced the maximum number of lesions;
reduced the median number of vesicles; decreased the median number of residual
lesions on day 28; and decreased the proportion of patients with fever,
anorexia, and lethargy by day 2. Treatment with acyclovir did not affect
varicella-zoster virus-specific humoral or cellular immune responses at 1 month
or 1 year following treatment.

Indications And Usage

Herpes
Zoster Infections: Acyclovir capsules, USP and acyclovir tablets, USP are
indicated for the acute treatment of herpes zoster (shingles).Genital
Herpes: Acyclovir capsules, USP and acyclovir tablets, USP are indicated
for the treatment of initial episodes and the management of recurrent episodes
of genital herpes.Chickenpox: Acyclovir capsules, USP and acyclovir tablets, USP
are indicated for the treatment of chickenpox (varicella).

Contraindications

Acyclovir is contraindicated for patients who develop hypersensitivity to
acyclovir or valacyclovir.

Warnings

Acyclovir capsules and tablets are intended for oral ingestion only. Renal
failure, in some cases resulting in death, has been observed with acyclovir
therapy (See ADVERSE REACTIONS: Observed During Clinical
Practice and OVERDOSAGE). Thrombotic
thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS), which has resulted
in death, has occurred in immunocompromised patients receiving acyclovir
therapy.

Precautions

Dosage adjustment is recommended when administering acyclovir to patients with
renal impairment (See DOSAGE AND ADMINISTRATION).
Caution should also be exercised when administering acyclovir to patients
receiving potentially nephrotoxic agents since this may increase the risk of
renal dysfunction and/or the risk of reversible central nervous system symptoms
such as those that have been reported in patients treated with intravenous
acyclovir. Adequate hydration should be maintained.

Information For Patients

Patients are instructed
to consult with their physician if they experience severe or troublesome adverse
reactions, they become pregnant or intend to become pregnant, they intend to
breastfeed while taking orally administered acyclovir, or they have any other
questions.Patients should be
advised to maintain adequate hydration.Herpes Zoster: There are no data on treatment
initiated more than 72 hours after onset of the zoster rash. Patients should be
advised to initiate treatment as soon as possible after a diagnosis of herpes
zoster.Genital Herpes Infections: Patients should be
informed that acyclovir is not a cure for genital herpes. There are no data
evaluating whether acyclovir will prevent transmission of infection to others.
Because genital herpes is a sexually transmitted disease, patients should avoid
contact with lesions or intercourse when lesions and/or symptoms are present to
avoid infecting partners. Genital herpes can also be transmitted in the absence
of symptoms through asymptomatic viral shedding. If medical management of a
genital herpes recurrence is indicated, patients should be advised to initiate
therapy at the first sign or symptom of an episode.Chickenpox: Chickenpox in otherwise healthy children
is usually a self-limited disease of mild to moderate severity. Adolescents and
adults tend to have more severe disease. Treatment was initiated within 24 hours
of the typical chickenpox rash in the controlled studies, and there is no
information regarding the effects of treatment begun later in the disease
course.

Drug Interactions

See CLINICAL PHARMACOLOGY: Pharmacokinetics.

Carcinogenesis, Mutagenesis, Impairment Of Fertility

The data presented below
include references to peak steady-state plasma acyclovir concentrations observed
in humans treated with 800 mg given orally 5 times a day (dosing appropriate for
treatment of herpes zoster) or 200 mg given orally 5 times a day (dosing
appropriate for treatment of genital herpes). Plasma drug concentrations in
animal studies are expressed as multiples of human exposure to acyclovir at the
higher and lower dosing schedules (See CLINICAL PHARMACOLOGY:
Pharmacokinetics).Acyclovir was tested in
lifetime bioassays in rats and mice at single daily doses of up to 450 mg/kg
administered by gavage. There was no statistically significant difference in the
incidence of tumors between treated and control animals, nor did acyclovir
shorten the latency of tumors. Maximum plasma concentrations were 3 to 6 times
human levels in the mouse bioassay and 1 to 2 times human levels in the rat
bioassay.Acyclovir was tested in
16 in vitro and in vivo
genetic toxicity assays. Acyclovir was positive in 5 of the assays.Acyclovir did not impair
fertility or reproduction in mice (450 mg/kg/day, p.o.) or in rats (25
mg/kg/day, s.c.). In the mouse study, plasma levels were 9 to 18 times human
levels, while in the rat study, they were 8 to 15 times human levels. At higher
doses (50 mg/kg/day, s.c.) in rats and rabbits (11 to 22 and 16 to 31 times
human levels, respectively) implantation efficacy, but not litter size, was
decreased. In a rat peri- and post-natal study at 50 mg/kg/day, s.c., there was
a statistically significant decrease in group mean numbers of corpora lutea,
total implantation sites, and live fetuses. No testicular
abnormalities were seen in dogs given 50 mg/kg/day, IV for 1 month (21 to 41
times human levels) or in dogs given 60 mg/kg/day orally for 1 year (6 to 12
times human levels). Testicular atrophy and aspermatogenesis were observed in
rats and dogs at higher dose levels.

Pregnancy

Teratogenic Effects: Pregnancy Category B. Acyclovir
administered during organogenesis was not teratogenic in the mouse (450
mg/kg/day, p.o.), rabbit (50 mg/kg/day, s.c. and IV), or rat (50 mg/kg/day,
s.c.). These exposures resulted in plasma levels 9 and 18, 16 and 106, and 11
and 22 times, respectively, human levels.There are no adequate
and well-controlled studies in pregnant women. A prospective epidemiologic
registry of acyclovir use during pregnancy was established in 1984 and completed
in April 1999. There were 749 pregnancies followed in women exposed to systemic
acyclovir during the first trimester of pregnancy resulting in 756 outcomes. The
occurrence rate of birth defects approximates that found in the general
population.However, the small size
of the registry is insufficient to evaluate the risk for less common defects or
to permit reliable or definitive conclusions regarding the safety of acyclovir
in pregnant women and their developing fetuses. Acyclovir should be used during
pregnancy only if the potential benefit justifies the potential risk to the
fetus.

Nursing Mothers

Acyclovir concentrations have been documented in breast milk in 2 women
following oral administration of acyclovir and ranged from 0.6 to 4.1 times
corresponding plasma levels. These concentrations would potentially expose the
nursing infant to a dose of acyclovir up to 0.3 mg/kg per day. Acyclovir should
be administered to a nursing mother with caution and only when indicated.

Pediatric Use

Safety and effectiveness of oral formulations of acyclovir in pediatric patients
less than 2 years of age have not been established.

Geriatric Use

Of 376 subjects who received acyclovir in a clinical study of herpes zoster
treatment in immunocompetent subjects ≥ 50 years of age, 244 were 65 and over
while 111 were 75 and over. No overall differences in effectiveness for time to
cessation of new lesion formation or time to healing were reported between
geriatric subjects and younger adult subjects. The duration of pain after
healing was longer in patients 65 and over. Nausea, vomiting, and dizziness were
reported more frequently in elderly subjects. Elderly patients are more likely
to have reduced renal function and require dose reduction. Elderly patients are
also more likely to have renal or CNS adverse events. With respect to CNS
adverse events observed during clinical practice, somnolence, hallucinations,
confusion, and coma were reported more frequently in elderly patients (See CLINICAL PHARMACOLOGY, ADVERSE REACTIONS: Observed During Clinical
Practice, and DOSAGE AND ADMINISTRATION).

Adverse Reactions

Herpes
Simplex: Short-Term Administration: The most
frequent adverse events reported during clinical trials of treatment of genital
herpes with acyclovir 200 mg administered orally 5 times daily every 4 hours for
10 days were nausea and/or vomiting in 8 of 298 patient treatments (2.7%).
Nausea and/or vomiting occurred in 2 of 287 (0.7%) patients who received
placebo.Long-Term Administration: The most frequent adverse
events reported in a clinical trial for the prevention of recurrences with
continuous administration of 400 mg (two 200 mg capsules) 2 times daily for 1
year in 586 patients treated with acyclovir were nausea (4.8%) and diarrhea
(2.4%). The 589 control patients receiving intermittent treatment of recurrences
with acyclovir for 1 year reported diarrhea (2.7%), nausea (2.4%), and headache
(2.2%).Herpes
Zoster: The most frequent adverse event reported during 3 clinical trials
of treatment of herpes zoster (shingles) with 800 mg of oral acyclovir 5 times
daily for 7 to 10 days in 323 patients was malaise (11.5%). The 323 placebo
recipients reported malaise (11.1%).Chickenpox: The most frequent adverse event reported during 3
clinical trials of treatment of chickenpox with oral acyclovir at doses of 10 to
20 mg/kg 4 times daily for 5 to 7 days or 800 mg 4 times daily for 5 days in 495
patients was diarrhea (3.2%). The 498 patients receiving placebo reported
diarrhea (2.2%).Observed During Clinical Practice: In addition to adverse
events reported from clinical trials, the following events have been identified
during post-approval use of acyclovir. Because they are reported voluntarily
from a population of unknown size, estimates of frequency cannot be made. These
events have been chosen for inclusion due to either their seriousness, frequency
of reporting, potential causal connection to acyclovir, or a combination of
these factors.General: Anaphylaxis, angioedema, fever, headache,
pain, peripheral edema. Nervous: Aggressive behavior, agitation, ataxia,
coma, confusion, decreased consciousness, delirium, dizziness, dysarthria,
encephalopathy, hallucinations, paresthesia, psychosis, seizure, somnolence,
tremors. These symptoms may be marked, particularly in older adults or in
patients with renal impairment (See PRECAUTIONS).Digestive: Diarrhea, gastrointestinal distress,
nausea. Hematologic and Lymphatic: Anemia, leukocytoclastic
vasculitis, leukopenia, lymphadenopathy, thrombocytopenia.Hepatobiliary Tract and Pancreas: Elevated liver
function tests, hepatitis, hyperbilirubinemia, jaundice.Musculoskeletal: Myalgia.Skin: Alopecia, erythema multiforme, photosensitive
rash, pruritus, rash, Stevens-Johnson syndrome, toxic epidermal necrolysis,
urticaria.Special Senses: Visual abnormalities.Urogenital: Renal failure, renal pain (may be
associated with renal failure), elevated blood urea nitrogen, elevated
creatinine, hematuria (See WARNINGS).

Overdosage

Overdoses involving ingestion of up to 100 capsules (20 g) have been reported.
Adverse events that have been reported in association with overdosage include
agitation, coma, seizures, and lethargy. Precipitation of acyclovir in renal
tubules may occur when the solubility (2.5 mg/mL) is exceeded in the
intratubular fluid. Overdosage has been reported following bolus injections or
inappropriately high doses and in patients whose fluid and electrolyte balance
were not properly monitored. This has resulted in elevated BUN and serum
creatinine and subsequent renal failure. In the event of acute renal failure and
anuria, the patient may benefit from hemodialysis until renal function is
restored (See DOSAGE AND ADMINISTRATION).

Dosage And Administration

Acute
Treatment of Herpes Zoster: 800 mg every 4 hours orally, 5 times daily
for 7 to 10 days.Genital
Herpes: Treatment of Initial Genital Herpes:
200 mg every 4 hours, 5 times daily for 10 days.Chronic Suppressive Therapy for Recurrent Disease:
400 mg 2 times daily for up to 12 months, followed by
re-evaluation. Alternative regimens have included doses ranging from 200 mg 3
times daily to 200 mg 5 times daily.The frequency and
severity of episodes of untreated genital herpes may change over time. After 1
year of therapy, the frequency and severity of the patient’s genital herpes
infection should be re-evaluated to assess the need for continuation of therapy
with acyclovir.Intermittent Therapy: 200 mg every 4 hours, 5 times
daily for 5 days. Therapy should be initiated at the earliest sign or symptom
(prodrome) of recurrence.Treatment of Chickenpox: Children (2 years of age
and older): 20 mg/kg per dose orally 4
times daily (80 mg/kg/day) for 5 days. Children over 40 kg should receive the
adult dose for chickenpox.Adults and children over 40 kg: 800 mg 4 times daily
for 5 days.Intravenous acyclovir is
indicated for the treatment of varicella-zoster infections in immunocompromised
patients.When therapy is
indicated, it should be initiated at the earliest sign or symptom of chickenpox.
There is no information about the efficacy of therapy initiated more than 24
hours after onset of signs and symptoms.Patients with Acute or Chronic Renal Impairment: In patients
with renal impairment, the dose of Acyclovir capsules and tablets should be
modified as shown in Table 3:Table 3: Dosage
Modification for Renal ImpairmentNormal DosageCreatinine Clearance                                     Adjusted Dosage RegimenRegimen(mL/min/1.73 m2)                     Dose(mg)Dosing Interval200 mg every      > 10                             200 every 4 hours, 5 times daily     4 hours  0 to 10                             200      every 12 hours 400 mg every      > 10                             400      every 12 hours     12 hours  0 to 10                             200      every 12 hours 800 mg every      > 25                             800 every 4 hours, 5 times daily     4 hours 10 to 25                             800      every 8 hours    0 to 10                             800      every 12 hours Hemodialysis: For patients who require hemodialysis, the mean
plasma half-life of acyclovir during hemodialysis is approximately 5 hours. This
results in a 60% decrease in plasma concentrations following a 6-hour dialysis
period. Therefore, the patient’s dosing schedule should be adjusted so that an
additional dose is administered after each dialysis.Peritoneal Dialysis: No supplemental dose appears to be
necessary after adjustment of the dosing interval.Bioequivalence of Dosage Forms: Acyclovir suspension was shown
to be bioequivalent to acyclovir capsules (n = 20) and one acyclovir 800 mg
tablet was shown to be bioequivalent to four acyclovir 200 mg capsules (n = 24).

How Supplied

Acyclovir capsules, USP
(white, opaque cap and body) containing 200 mg acyclovir, USP and printed with
“RX 652” on both the cap and the body. Bottle of 20 (NDC
63304-652-20)Bottle of 1000 (NDC
63304-652-10)Acyclovir tablets, USP
(white, oval-shaped, unscored) containing 800 mg acyclovir, USP and debossed
with “RX 505” on one side. Bottle of 50 (NDC
63304-505-50)Bottle of 180 (NDC
63304-505-28)Acyclovir tablets, USP
(white, oval-shaped, unscored) containing 400 mg acyclovir, USP and debossed
with “RX 504” on one side. Bottle of 50 (NDC
63304-504-50)Bottle of 180 (NDC
63304-504-28)Store
at 20 - 25° C (68 - 77° F) [See USP Controlled Room Temperature]. Protect from
moisture.Call your doctor for
medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.Manufactured for:Ranbaxy Pharmaceuticals
Inc.Jacksonville, FL 32257
USAby: Ohm Laboratories
Inc.North Brunswick, NJ
08902 USA April 2009

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