Acyclovir

DRUG INFORMATION

  ADULT
    - ZOVIRAX Cream should be applied 5 times per day for 4 days. Therapy should be
      initiated as early as possible following the onset of signs or symptoms of herpes
      labialis, i.e. during the prodrome or when lesions appear. For adolescents 12
      years of age and older, the dosage is the same as in adults. • Apply 5 times a day
      for 4 days. ( 2 ) • Administer immediately following the onset of cold sore
      lesions. ( 2 )
      Source: US FDA label for acyclovir (Zovirax), section 'dosage and administration',
      retrieved 2026-08-29

  CHILD
    - An open-label, uncontrolled trial with ZOVIRAX Cream was conducted in 113 patients
      aged 12 to 17 years with recurrent herpes labialis. In this trial, therapy was
      applied using the same dosing regimen as in adults and subjects were followed for
      adverse events. The safety profile was similar to that observed in adults. Safety
      and effectiveness in pediatric patients less than 12 years of age have not been
      established.
      Source: US FDA label for acyclovir (Zovirax), section 'pediatric use', retrieved
      2026-08-29
    - ZOVIRAX Cream should be applied 5 times per day for 4 days. Therapy should be
      initiated as early as possible following the onset of signs or symptoms of herpes
      labialis, i.e. during the prodrome or when lesions appear. For adolescents 12
      years of age and older, the dosage is the same as in adults. • Apply 5 times a day
      for 4 days. ( 2 ) • Administer immediately following the onset of cold sore
      lesions. ( 2 )
      Source: US FDA label for acyclovir (Zovirax), section 'dosage and administration',
      retrieved 2026-08-29

  RENAL IMPAIRMENT
    - No kidney-impairment dose in this label. Not a statement that none is needed.
      Source: Read and found silent: the US FDA label for acyclovir (Zovirax), retrieved
      2026-08-29

  HEPATIC IMPAIRMENT
    - No liver-impairment dose in this label. Not a statement that none is needed.
      Source: Read and found silent: the US FDA label for acyclovir (Zovirax), retrieved
      2026-08-29

  PREGNANCY
    - Risk Summary Acyclovir is minimally absorbed systemically following topical route
      of administration, and maternal use is not expected to result in fetal exposure to
      the ZOVIRAX Cream [see Clinical Pharmacology (12.3) ] .
      Source: US FDA label for acyclovir (Zovirax), section 'pregnancy', retrieved
      2026-08-29
    - Experience with topical acyclovir use in pregnant women over several decades,
      based on published literature including observational studies, has not identified
      a drug-associated risk of major birth defects, miscarriage or adverse maternal or
      fetal outcomes.
      Source: US FDA label for acyclovir (Zovirax), section 'pregnancy', retrieved
      2026-08-29
    - Animal reproduction studies with systemic exposure of acyclovir have been
      conducted.
      Source: US FDA label for acyclovir (Zovirax), section 'pregnancy', retrieved
      2026-08-29

  BREASTFEEDING
    - In the U.S. general population, the estimated background risk of major birth
      defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15%
      to 20%, respectively. 8.2 Lactation Risk Summary Acyclovir is minimally absorbed
      systemically following topical route of administration, and breastfeeding is not
      expected to result in exposure of the child to ZOVIRAX Cream [see Clinical
      Pharmacology (12.3) ] .
      Source: US FDA label for acyclovir (Zovirax), section 'use in specific
      populations', retrieved 2026-08-29
    - There are no data on the effects of ZOVIRAX on the breastfed infant or on milk
      production.
      Source: US FDA label for acyclovir (Zovirax), section 'use in specific
      populations', retrieved 2026-08-29
    - The developmental and health benefits of breastfeeding should be considered along
      with the mother’s clinical need for ZOVIRAX Cream and any potential adverse
      effects on the breastfed child from ZOVIRAX Cream or from the underlying maternal
      condition. 8.4 Pediatric Use An open-label, uncontrolled trial with ZOVIRAX Cream
      was conducted in 113 patients aged 12 to 17 years with recurrent herpes labialis.
      Source: US FDA label for acyclovir (Zovirax), section 'use in specific
      populations', retrieved 2026-08-29