Acyclovir topical

Name: Acyclovir topical

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

Acyclovir

Routes

Dosage Forms

Strengths

Brand Names

Manufacturer

Topical

Cream

5%

Zovirax (with propylene glycol)

Biovail

Ointment

5%

Zovirax

Biovail

Before Using acyclovir

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For acyclovir, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to acyclovir or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Studies on acyclovir have been done only in adult patients, and there is no specific information comparing use of topical acyclovir in children with use in other age groups.

Geriatric

Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults. Although there is no specific information comparing the use of topical acyclovir in the elderly with use in other age groups, acyclovir is not expected to cause different side effects or problems in older people than it does in younger adults.

Pregnancy

Pregnancy Category Explanation
All Trimesters B Animal studies have revealed no evidence of harm to the fetus, however, there are no adequate studies in pregnant women OR animal studies have shown an adverse effect, but adequate studies in pregnant women have failed to demonstrate a risk to the fetus.

Breast Feeding

Studies in women suggest that this medication poses minimal risk to the infant when used during breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking acyclovir, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using acyclovir with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Foscarnet

Using acyclovir with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Fosphenytoin
  • Mycophenolate Mofetil
  • Mycophenolic Acid
  • Phenytoin
  • Valproic Acid

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

Tell your doctor if your herpes simplex infection keeps coming back while you are using acyclovir.

Precautions While Using acyclovir

Women with genital herpes may be more likely to get cancer of the cervix (opening to the womb). Therefore, it is very important that Pap tests be taken at least once a year to check for cancer. Cervical cancer can be cured if found and treated early.

If your symptoms do not improve within 1 week, or if they become worse, check with your doctor.

Consider the possibility of viral resistance to acyclovir if little or no improvement in symptoms during therapy.

The areas affected by herpes should be kept as clean and dry as possible. Also, wear loose-fitting clothing to avoid irritating the sores (blisters).

Herpes infection of the genitals can be caught from or spread to your partner during any sexual activity. Although you may get herpes even though your sexual partner has no symptoms, the infection is more likely to be spread if sores are present. This is true until the sores are completely healed and the scabs have fallen off. The use of a condom (prophylactic) may help prevent the spread of herpes. However, spermicidal (sperm-killing) jelly or a diaphragm will not help prevent the spread of herpes. Therefore, it is best to avoid any sexual activity if either you or your partner has any symptoms of herpes. It is also important to remember that acyclovir will not keep you from spreading herpes to others.

Pronunciation

(ay SYE kloe veer)

Brand Names U.S.

  • Sitavig
  • Zovirax

Dosing Renal Impairment

There are no dosage adjustments provided in the manufacturer’s labeling. However, dosage adjustment is unlikely due to low systemic absorption.

Adverse Reactions

>10%: Dermatologic: Local pain (ointment 30%; mild; includes transient burning and stinging)

1% to 10%:

Central nervous system: Lethargy (buccal tablet 1%)

Dermatologic: Erythema (buccal tablet 1%), skin rash (buccal tablet 1%)

Gastrointestinal: Aphthous stomatitis (buccal tablet 1%), gingival pain (buccal tablet 1%)

Local: Application site reaction (cream 5%; including dry lips, desquamation, dryness of skin, cracked lips, burning skin, pruritus, flakiness of skin, and stinging on skin); application site irritation (buccal tablet 1%)

<1% (Limited to important or life-threatening): Anaphylaxis, eczema

Pregnancy Risk Factor B Pregnancy Considerations

Teratogenic effects were not observed in animal studies. When administered orally, acyclovir crosses the placenta. Refer to the Acyclovir (Systemic) monograph for details. The amount of acyclovir available systemically following topical application of the cream or ointment is significantly less in comparison to oral doses.

For the Consumer

Applies to acyclovir topical: topical cream, topical ointment

Along with its needed effects, acyclovir topical may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Some side effects of acyclovir topical may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common
  • Mild pain, burning, or stinging
Less common
  • Itching
Rare
  • Itching, stinging, or redness of the genital area
  • skin rash

For Healthcare Professionals

Applies to acyclovir topical: topical cream, topical ointment

General

Acyclovir topical has been generally well tolerated and adverse effects are uncommon.[Ref]

Local

Local side effects associated with the ointment have included mild pain (including transient stinging and burning) and local pruritus. Dryness of skin, flakiness of skin, dry lips, cracked lips, burning skin, pruritus, and stinging on skin have been reported at the site of topical application in less than 1% of patients using acyclovir topical cream. Edema and/or pain at the application site have been reported during postmarketing experience with acyclovir topical ointment. The pain is generally due to manipulation of the herpetic lesions rather than a reaction to the drug itself. Application site reactions (including signs and symptoms of inflammation) have been reported during postmarketing experience with acyclovir topical cream.[Ref]

Dermatologic

Dermatologic side effects have included rash and pruritus during postmarketing experience with acyclovir topical ointment. Contact dermatitis and eczema have been reported during postmarketing experience with acyclovir topical cream.[Ref]

Hypersensitivity

Hypersensitivity side effects have included angioedema and anaphylaxis during postmarketing experience with acyclovir topical cream.

Some side effects of acyclovir topical may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Acyclovir topical Breastfeeding Warnings

There are no data on the excretion of topically applied acyclovir into breast milk. Systemically administered acyclovir is excreted into and concentrated in human milk. However, the agent is used to treat viral infections in the neonate and adverse effects in nursing infants exposed via breast milk have not been reported in the literature. In one woman, measurement of breast milk levels revealed an infant would be exposed to 1% of the maternal dosage or 0.73 mg/kg/day. No adverse effects were noted in this nursing infant. Acyclovir is considered compatible with breast-feeding by the American Academy of Pediatrics. Breast-feeding should be avoided if herpetic lesions are on or near the breast.

Acyclovir Identification

Substance Name

Acyclovir

CAS Registry Number

59277-89-3

Drug Class

Antiinfective Agents

Antiviral Agents

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