Dosing and uses of Zovirax topical, Sitavig (acyclovir topical)
Dosing Strengths & Forms
topical cream
- 5%
topical ointment
- 5%
mucoadhesive buccal tablet
- 50mg (Sitavig)
Herpes Labialis
Cream/ointment
- Limited, non-life-threatening mucocutaneous Herpes simplex virus infections in immunocompromised patients
- Apply topically to lips and around mouth 5 times per day for 4 days; initiate as soon as possible after first signs and symptoms
Mucoadhesive buccal tablet
- Recurrent herpes labialis (cold sores) in immunocompetent adults
- Apply one 50 mg buccal tablet as a single dose to the upper gum (canine fossa) region
- Should be applied within 1 hr after the onset of prodromal symptoms and before the appearance of any signs of Herpes labialis
Genital Herpes
Initial genital herpes
Apply sufficient quantity to adequately cover all lesions q3hr, 6 times/day for 7 days
Herpetic Keratitis (Orphan)
Acute herpetic keratitis caused by Herpes simplex virus types 1 and 2
Orphan indication sponsors
- GlaxoSmithKline, One Franklin Plaza, Philadelphia, PA 19101
- Fera Pharmaceuticals, 134 Birch Hill Road, Locust Valley, NY 11560
Administration
Cream/ointment
- The dose size per application will vary depending on the total lesion area but should approximate a one-half-inch ribbon of ointment per 4 square inches of surface area
- A finger cot or rubber glove should be used when applying, to prevent autoinoculation of other body sites and transmission of infection to other persons
Mucoadhesive buccal tablet
- Do not crush, chew, suck, or swallow tablets
Pediatric dosage forms and strengths
Dosing Strengths & Forms
topical cream
- 5%
topical ointment
- 5%
Herpes Labialis
Recurrent herpes labialis (cold sores) in adults and adolescents
<12 years: Safety and efficacy not established
≥12 years: As adults, apply cream/ointment topically to lips and around mouth 5 times per day for 4 days; initiate as soon as possible after first signs and symptoms
Zovirax topical, Sitavig (acyclovir topical) adverse (side) effects
>10%
Burning/stinging (30%)
1-10%
Pruritus (4%)
<1%
Dry lips (<1%)
Rash (0.3%)
Frequency not defined
Angioedema
Vulvitis
Warnings
Contraindications
Hypersensitivity
Cautions
Not recommended for recurrent infections
Use caution in immunocompromised patients
Avoid physical contact when lesions are present
For external use only; not for use on the eye or inside mouth
Pregnancy and lactation
Pregnancy category: B
Lactation: Excretion in milk unknown; systemic exposure is minimal after topical application
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Zovirax topical, Sitavig (acyclovir topical)
Mechanism of action
Exerts its antiviral effect on herpes simplex viruses and varicella zoster virus by interfering with DNA synthesis and inhibiting viral replication
Helps shed herpes virus quicker and reduces pain and duration; used for management of initial episodes of herpes genitalis and in mucocutaneous herpes simplex viral infections in immunocompromised patients
Absorption
MinimaL
Metabolism
In cells infected with herpes viruses, principally by intracellular phosphorylation of drug by virus-coded thymidine kinase and several cellular enzymes
Elimination
Excretion: Urine
