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Related to acyclovir: Zovirax


a synthetic acyclic purine nucleoside with selective antiviral activity against the human herpesviruses, used in treatment of genital and mucocutaneous herpesvirus infections in both immunocompromised patients and those who are not. Administered orally, topically, or intravenously.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


acyclovir sodium


Pharmacologic class: Acyclic purine nucleoside analogue

Therapeutic class: Antiviral

Pregnancy risk category B


Inhibits viral DNA polymerase, thereby inhibiting replication of viral DNA. Specific for herpes simplex types 1 (HSV-1) and 2 (HSV-2), varicellazoster virus, Epstein-Barr virus, and cytomegalovirus (CMV).


Capsules: 200 mg

Cream: 5% in 2-g tube

Injection: 50 mg/ml

Ointment: 5% in 15-g tube

Powder for injection: 500 mg/vial, 1,000 mg/vial

Suspension: 200 mg/5 ml

Tablets: 400 mg, 800 mg

Indications and dosages

Acute treatment of herpes zoster (shingles)

Adults: 800 mg P.O. q 4 hours while awake (five times/day) for 7 to 10 days

Initial episode of genital herpes

Adults: 200 mg P.O. q 4 hours while awake (1,000 mg/day) for 10 days

Chronic suppressive therapy for recurrent genital herpes episodes

Adults: 400 mg P.O. b.i.d., or 200 mg P.O. three to five times daily for up to 12 months

Intermittent therapy for recurrent genital herpes episodes

Adults: 200 mg P.O. q 4 hours while awake (five times/day) for 5 days, initiated at first sign or symptom of recurrence

Management of initial episodes of genital herpes and limited, non-life-threatening mucocutaneous herpes simplex virus infections in immunocompromised patients

Adults: Apply approximately ½″ ribbon of ointment per 4 square inches of surface area to sufficiently cover all lesions q 3 hours, six times daily for 7 days.

Treatment of recurrent herpes labialis (cold sores)

Adults and adolescents ages 12 and older: Apply cream to infected area five times daily for 4 days.

Varicella (chickenpox)

Adults and children weighing more than 40 kg (88 lb): 800 mg P.O. q.i.d. for 5 days

Children older than age 2: 20 mg/kg P.O. q.i.d. for 5 days

Mucosal and cutaneous HSV-1 and HSV-2 in immunocompromised patients

Adults and children older than age 12: 5 mg/kg I.V. infusion over 1 hour given q 8 hours for 7 days

Children younger than age 12: 10 mg/kg I.V. infusion over 1 hour given q 8 hours for 7 days

Herpes simplex encephalitis

Adults and children older than age 12: 10 mg/kg I.V. over 1 hour given q 8 hours for 10 days

Children ages 3 months to 12 years: 20 mg/kg I.V. over 1 hour given q 8 hours for 10 days

Children from birth to 3 months: 10 mg/kg I.V. over 1 hour given q 8 hours for 10 days

Varicella zoster infections in immunocompromised patients

Adults and adolescents older than age 12: 10 mg/kg I.V. over 1 hour given q 8 hours for 7 days

Children younger than age 12: 20 mg/kg I.V. over 1 hour given q 8 hours for 7 days

Dosage adjustment

• Renal impairment

• Obesity (adult dosage based on ideal weight)

• Elderly patients

Off-label uses

• Herpes zoster encephalitis

• CMV and HSV infection after bone marrow or kidney transplantation

• Infectious mononucleosis

• Varicella pneumonia


• Hypersensitivity to drug or valacyclovir


Use cautiously in:

• preexisting serious neurologic, hepatic, pulmonary, or fluid or electrolyte abnormalities

• renal impairment

• obesity

• pregnant or breastfeeding patients.


• Make sure patient is adequately hydrated before starting therapy.

• Give single I.V. dose by infusion over at least 1 hour to minimize renal damage.

• Don't give by I.V. bolus or by I.M. or subcutaneous route.

• Be aware that absorption of topical acyclovir is minimal.

Adverse reactions

CNS: aggressive behavior, dizziness, malaise, weakness, paresthesia, headache; with I.V. use-encephalopathic changes (lethargy, tremors, obtundation, confusion, hallucinations, agitation, seizures, coma)

CV: peripheral edema

EENT: vision abnormalities

GI: nausea, vomiting, diarrhea

GU: proteinuria, hematuria, crystalluria, vaginitis, candidiasis, changes in menses, vulvitis, oliguria, renal pain, renal failure, glomerulonephritis Hematologic: anemia, lymphadenopathy, thrombocytopenia, thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (in immunocompromised patients), disseminated intravascular coagulation, hemolysis, leukopenia, leukoclastic vasculitis

Hepatic: jaundice, hepatitis

Musculoskeletal: myalgia

Skin: photosensitivity rash, pruritus, angioedema, alopecia, urticaria, severe local inflammatory reactions (with I.V. extravasation), toxic epidermal necrolysis, erythema multiforme

Other: gingival hyperplasia, fever, excessive thirst, pain at injection site, anaphylaxis, Stevens-Johnson syndrome


Drug-drug. Interferon: additive effect

Nephrotoxic drugs: increased risk of nephrotoxicity

Probenecid: increased acyclovir blood level

Zidovudine: increased CNS effects, especially drowsiness

Drug-diagnostic tests. Alanine aminotransferase, aspartate aminotransferase, bilirubin, blood urea nitrogen: increased levels

Patient monitoring

• Monitor fluid intake and output.

• Assess for signs and symptoms of encephalopathy.

• Evaluate patient frequently for adverse reactions, especially bleeding tendency.

• Monitor CBC with white cell differential and kidney function test results.

Patient teaching

• Instruct patient to keep taking drug exactly as prescribed, even after symptoms improve.

• Advise patient to drink enough fluids to ensure adequate urinary output.

• Tell patient to monitor urine output and report significant changes.

Instruct patient to immediately report unusual bleeding or bruising.

• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.

• Advise patient to minimize GI upset by eating small, frequent servings of food and drinking plenty of fluids.

• Tell patient to use soft toothbrush and electric razor to avoid injury to gums and skin.

• Advise patient to avoid sexual intercourse when visible herpes lesions are present.

• Inform patient that he may need to undergo regular blood testing during therapy.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.

McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved


(ā-sī′klō-vîr, -klə-)
A synthetic purine nucleoside analog, C8H10N5O3, derived from guanine and used in the treatment of herpes simplex, herpes zoster, and varicella-zoster virus infections.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.


A nucleoside analogue used to manage viral infections in patients with bone marrow transplants, chemotherapy-induced or acquired immunosuppression—e.g., AIDS.
Indications HSV-1, HSV-2, HVZ, and CMV. Acyclovir is considered safe for paediatric chickenpox (varicella-zoster) if begun in the first 24 hours of rash, although it is unclear if it reduces the rare serious complications of chickenpox or is more effective than vidarabine in reducing viral shedding by HSV-infected infants. 
Adverse effects Upset stomach, headache, nausea; hair loss with chronic use.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.


Zovirax Infectious disease A nucleoside analogue used to manage viral infections in Pts with BMTs, chemotherapy-induced or acquired immunosuppression–eg, AIDS Indications HSV-1, HSV-2, HVZ Adverse effects Upset stomach, headache, nausea; hair loss from prolonged use. Cf Foscarnet, Gancyclovir.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


An antiviral drug that is available under the trade name Zovirax, in oral, intravenous, and topical forms. The drug blocks the replication of the varicella zoster virus.
Mentioned in: Chickenpox, Shingles
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.

antiviral agents 

Substances which inhibit the growth of a virus (e.g. herpes) by inhibiting DNA or RNA synthesis. Common agents include aciclovir (acyclovir), idoxuridine, ganciclovir, trifluoridine (trifluorothymidine) and vidarabine. See herpetic keratitis; virus.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann


A synthetic nucleoside medication used to treat chicken pox, shingles, and the genital form of herpes simplex symptoms.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Acyclovir is the first BPCA drug labelling change in 2019 and others are likely to follow.
In another study, in 18 patients, HSV PCR was reported positive from 9 to 28 days after initiation of acyclovir, but it was not correlated with an unfavorable outcome (13).
Acyclovir levels may be obtained from the blood, serum, cerebrospinal fluid, or urine, based on availability; however, levels have not been shown to correlate with clinical presentation [2, 7].
In these cases, IV acyclovir was the staple of treatment [2, 3].
Valacyclovir is a prodrug which is converted in vivo via hepatic first-pass metabolism to acyclovir, which is then modified by viral thymidine kinase and prevents viral proliferation.
Topical imiquimod has also been used successfully in the treatment of hypertrophic and pseudotumoral genital herpes simplex infection refractory to acyclovir and foscarnet [6, 12].
The aim of this study was the evaluation of effect of acyclovir and aqueous extract of propolis on HSV 1 in cell culture.
Patient receiving Acyclovir, allocated in group A, after 1st week there was partial response for all the patient after 2nd week 10 patient were completely cured and 20 patient have partial response after 4th week on ward all Patient were completely cured.
Oral valacyclovir and famcyclovir are equivalent to oral acyclovir. Adding topical acyclovir to oral acyclovir doesn't produce additional benefit (SOR: B, RCTs).
Antiviral agents licensed currently for the treatment of herpesvirus infections include acyclovir and its derivatives, nucleoside analogues which function as DNA chain terminators, ultimately preventing elongation of viral DNA (De Clercq 2004).
The pharmacy's cost for a 30-gram tube of acyclovir from the generic maker is around $600--and the pharmacy has its own costly bureaucratic mandates to contend with.