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BMJ Clinical Evidence Jun 2015Chickenpox is extremely contagious. More than 90% of unvaccinated people will become infected during their lifetime, but infection occurs at different ages in different... (Review)
Review
INTRODUCTION
Chickenpox is extremely contagious. More than 90% of unvaccinated people will become infected during their lifetime, but infection occurs at different ages in different parts of the world. In the US, the UK, and Japan, more than 80% of people have been infected by the age of 10 years, and by the age of 20 to 30 years in India, South East Asia, and the West Indies. It is usually a mild and self-limiting disease, but it can be severely complicated by pneumonitis or disseminated disease in some individuals, particularly neonates and those who are immunocompromised.
METHODS AND OUTCOMES
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatment for chickenpox in healthy adults and children (including neonates) within 24 hours after onset of rash? What are the effects of treatment for chickenpox in healthy adults and children (including neonates) later than 24 hours after onset of rash? What are the effects of treatment for chickenpox in immunocompromised adults and children (including neonates)? We searched: Medline, Embase, The Cochrane Library, and other important databases up to January 2014 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review).
RESULTS
We found six studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
CONCLUSIONS
In this systematic overview we present information relating to the effectiveness and safety of aciclovir, within 24 hours of onset of rash or later than 24 hours of onset of rash, in otherwise-healthy adults and children (including neonates); and aciclovir in immunocompromised adults and children (including neonates).
Topics: Acyclovir; Chickenpox; Humans; Immunocompromised Host; India; Treatment Outcome
PubMed: 26077272
DOI: No ID Found -
Journal of Veterinary Pharmacology and... Sep 1992The pharmacokinetics of intravenous (i.v.) and intramuscular (i.m.) single-dose administration of acyclovir were determined in Quaker parakeets. After i.v. injection at... (Comparative Study)
Comparative Study
The pharmacokinetics of intravenous (i.v.) and intramuscular (i.m.) single-dose administration of acyclovir were determined in Quaker parakeets. After i.v. injection at a dose of 20 mg/kg of acyclovir, elimination half-life was estimated at 0.65 h, volume of distribution at steady state was 627.65 ml/kg, and clearance was 11.22 ml/kg/min. The estimated pharmacokinetic values after i.m. injection at a dose of 40 mg/kg of acyclovir were an elimination half-life of 0.71 h and a bioavailability of 90.1%. The peak plasma acyclovir concentration occurred at 15 min when the drug was administered i.m. Plasma concentrations of acyclovir were undetectable 4-6 h after i.v. administration and 6-8 h after i.m. administration. Oral (capsules) and intravenous (sodium salt) formulations of acyclovir were given by gavage at 80 mg/kg. Peak concentrations with the sodium salt formulation were lower and developed more slowly than with the capsules. In studies designed to detect excessive drug accumulation or adverse side effects, acyclovir was administered i.m. at 40 mg/kg every 8 h for 7 days. Plasma concentrations were determined 15 min after (peak) and just prior to drug administration (trough). In another study acyclovir was gavaged at a dose of 80 mg/kg every 8 h for 4 days. Acyclovir plasma concentrations were determined just prior to and 2 h after drug administration. In both experiments, the birds maintained normal appetite and weight and did not exhibit excessive drug accumulation. Acyclovir plasma concentrations ranging from 2.07 +/- 1.09 micrograms/ml to 3.93 +/- 1.13 micrograms/ml were maintained for 4 days when acyclovir was administered in the feed and water (sole source of food and water).(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: Acyclovir; Animals; Half-Life; Injections, Intramuscular; Injections, Intravenous; Metabolic Clearance Rate; Parakeets; Species Specificity
PubMed: 1433488
DOI: 10.1111/j.1365-2885.1992.tb01014.x -
Annales de Dermatologie Et de... May 2002Valaciclovir is an aciclovir pro-drug considerably improving its oral availability. Its antiviral activity in vivo is related to that of aciclovir, the principle target... (Review)
Review
Valaciclovir is an aciclovir pro-drug considerably improving its oral availability. Its antiviral activity in vivo is related to that of aciclovir, the principle target of which is the herpes virus. Following digestive absorption, valaciclovir is rapidly transformed into aciclovir. The mean absolute bioavailability of aciclovir is of 54.2% after a single oral dose of 1,000 mg of valaciclovir, i.e., a bioavailability 3 to 5-fold greater than after oral ingestion of aciclovir. The plasma pharmacokinetic profile of valaciclovir and aciclovir observed in volunteers infected by HIV is superimposable on that of healthy subjects. In elderly patients, exposure to aciclovir is enhanced, probably because of the alteration in glomerular filtration. In patients exhibiting agranulocytosis following poly-chemotherapy, the pharmacokinetic parameters are superimposable on those observed in healthy patients. In patients with hepatic failure, there appears no need to adapt the dose, since exposure to aciclovir does not appear altered. However, the dose of valaciclovir must be adapted to renal function. During the first-episode of herpes genitalis, valaciclovir, at the dose of 500 or 1,000 mg twice daily, is as effective as 200 mg of aciclovir five times per day. In recurrent herpes genitalis, 500 mg twice daily of valaciclovir is as effective as 1,000 mg twice daily or 200 mg five times a day of aciclovir. Valaciclovir prevents recurrence herpes genitalis with a dose-dependent effect, and doses of 500 and 1,000 mg/day are as effective as 400 mg twice daily of aciclovir. There are few studies on the efficacy of valaciclovir in the treatment of oro-facial herpes. In the treatment of herpes zoster in patients aged over 50, the principle benefit provided by valaciclovir at the dose of 1,000 mg twice daily, is the decrease in the percentage of patients presenting post-zoster pain and its duration. High doses of valaciclovir (8 capsules/day) provide efficient prevention of infections related to the cyto-megalo-virus (CMV) in immunodepressed patients due to HIV infection or following renal transplantation. Tolerance to valaciclovir, like its active metabolite aciclovir, is generally good. Central neurological toxicity is frequently observed with high doses, but regresses on withdrawal. The official indications in France are the curative and preventive treatment of herpes genitalis infections, the prevention of post-zoster pain and the ocular complications of ophthalmologic herpes in immunocompetent adults, and the prevention of CMV infections after organ grafting.
Topics: Acyclovir; Humans; Prodrugs; Valacyclovir; Valine; Virus Diseases
PubMed: 12124513
DOI: No ID Found -
Scandinavian Journal of Infectious... 1985Acyclovir (Zovirax) is a highly specific antiherpes virus agent. Extensive investigations of the pharmacokinetics in man have shown it to have a useful half-life of...
Acyclovir (Zovirax) is a highly specific antiherpes virus agent. Extensive investigations of the pharmacokinetics in man have shown it to have a useful half-life of about three hours and to be largely excreted unchanged in the urine. Crystaluria can be avoided provided the patient is well hydrated and attention is paid to the dosing instructions especially in patients with renal failure. In vitro ED50s (the drug concentration inhibiting virus replication by 50%) bear some general relevance to effective plasma levels in man. A new prodrug of acyclovir, 2-amino-9-[2-hydroxyethoxy methyl]-9H-purine (A515U), which is converted to acyclovir by xanthine oxidase is rapidly absorbed from the human gut and converted to acyclovir. This prodrug provides the opportunity to design regimes that are more convenient for the patient and may be more effective than acyclovir itself in the therapy of the less sensitive herpes viruses (e.g. Epstein-Barr virus and the Cytomegalovirus).
Topics: Absorption; Acyclovir; Administration, Oral; Adolescent; Adult; Child; Child, Preschool; Digestive System; Half-Life; Humans; Infant; Infant, Newborn; Kidney; Kinetics
PubMed: 3868024
DOI: No ID Found -
Pediatric Blood & Cancer Oct 2008Valacyclovir, an orally administered pro-drug of acyclovir, is utilized in the therapy of herpes simplex and herpes zoster infections. Little data regarding the...
BACKGROUND
Valacyclovir, an orally administered pro-drug of acyclovir, is utilized in the therapy of herpes simplex and herpes zoster infections. Little data regarding the pharmacokinetics, safety and tolerability are available for pediatric patients. This report describes acyclovir pharmacokinetics following valacyclovir administration in immunocompromised pediatric patients, compares pharmacokinetic parameters following oral valacyclovir and IV acyclovir, and provides a limited assessment of efficacy in the setting of active herpes zoster infection.
PROCEDURE
A total of 37 immunocompromised children were enrolled on one of two studies. Pharmacokinetic data are available for 32 patients following valacyclovir (15 mg/kg) administration, 11 of whom also had pharmacokinetic sampling following IV acyclovir administration. Three patients received valacyclovir as treatment for herpes zoster infections.
RESULTS
Mean (+/-SD) C(max) values for acyclovir following oral valacyclovir were 18.8 +/- 7 microM with a total exposure of 4,106 +/- 1,519 microM min. The mean bioavailability of acyclovir from valacyclovir was 64%. Grade 1 nausea and emesis, which occurred in five patients was the only valacyclovir-related toxicity. Two of the three patients treated for herpes zoster had complete scabbing of lesions by day 9.
CONCLUSION
Valacyclovir (15 mg/kg) was well tolerated in pediatric patients and demonstrated excellent bioavailability. Consideration should be given to the use of oral valacyclovir for the treatment of herpes zoster in clinically stable pediatric oncology patients.
Topics: Acyclovir; Administration, Oral; Adolescent; Child; Child, Preschool; Drug-Related Side Effects and Adverse Reactions; Female; Humans; Immunocompromised Host; Male; Valacyclovir; Valine
PubMed: 18561175
DOI: 10.1002/pbc.21638 -
MCN. the American Journal of Maternal... 1992
Topics: Acyclovir; Chickenpox; Child; Humans; Randomized Controlled Trials as Topic
PubMed: 1406119
DOI: 10.1097/00005721-199209000-00027 -
Oral Surgery, Oral Medicine, and Oral... Jan 1984Acyclovir (Zovirax) is a qualified success as an effective and nontoxic antiviral chemotherapeutic agent and at present is approved for the treatment of initial genital... (Clinical Trial)
Clinical Trial
Acyclovir (Zovirax) is a qualified success as an effective and nontoxic antiviral chemotherapeutic agent and at present is approved for the treatment of initial genital herpes and limited life-threatening cutaneous herpes simplex viral infections in the immunocompromised host. Its efficacy in Epstein-Barr, varicella-zoster, and cytomegalorvirus infections appears less promising. According to one controlled study, its efficacy in the treatment of herpes labialis (HSV-1) infections has been disappointing. The highly selective action of acyclovir against viral DNA polymerase and its inhibition of viral DNA chain elongation result in a low incidence of human (host cell) toxicity, as manifested by local irritation at injection sites and a modest incidence of adverse renal effects, which can be reduced by judicious drug use. Newer antiviral agents now under development hold substantial promise for the future of antiviral chemotherapy.
Topics: Acyclovir; Clinical Trials as Topic; Drug Resistance, Microbial; Herpesviridae Infections; Humans; Kinetics; Simplexvirus
PubMed: 6320078
DOI: 10.1016/0030-4220(84)90258-5 -
Revue de L'infirmiere Feb 1987
Topics: Acyclovir; Humans
PubMed: 3645740
DOI: No ID Found -
Deutsche Medizinische Wochenschrift... May 1994
Topics: Acyclovir; Herpes Zoster; Humans
PubMed: 8187617
DOI: No ID Found -
Pediatrie 1993The authors report two cases of cutaneous recurrent herpes occurring after a neonatal herpes simplex virus type 2 (HSV2) infection and comment on the role of acute or... (Review)
Review
The authors report two cases of cutaneous recurrent herpes occurring after a neonatal herpes simplex virus type 2 (HSV2) infection and comment on the role of acute or suppressive therapy by aciclovir (ACV). The two infants were not treated by ACV after the neonatal period. None of the recurrent cutaneous herpes episodes was followed by viral widespread. One case reported by Bergström et al on a relapse of HSV2 encephalitis occurring after a cutaneous herpes in a child argues for the use of ACV in recurrent herpes. However, ACV might alter host defense response to HSV2 infection in neonates and children. Thus, it seems not yet recommended to use ACV either as acute or suppressive therapy in recurrent cutaneous herpes unless a progression of the viral disease is noted.
Topics: Acyclovir; Female; Herpes Simplex; Humans; Infant, Newborn; Male; Recurrence
PubMed: 7777392
DOI: No ID Found