How does this medication work? What will it do for me?

Acyclovir topical is used to manage initial episodes of herpes infections. It is an antiviral medication that helps to reduce the pain and severity of herpes lesions or sores.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are using this medication, speak to your doctor. Do not stop using this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to use this medication if their doctor has not prescribed it.

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What form(s) does this medication come in?

Each gram of ointment contains acyclovir 50 mg. Nonmedicinal ingredient: polyethylene glycol base.

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How should I use this medication?

Apply the medication liberally to the affected area 4 to 6 times daily for up to 10 days as directed by your doctor. A sufficient quantity of ointment should be applied to adequately cover all lesions. When applying, wear a finger cot or rubber glove to decrease the chances of spreading the infection to other sites or other people. You should start using this medication as soon as possible following the onset of signs and symptoms.

Do not use this medication in the eye or on mucous membrane such as inside surfaces of the mouth or vagina. This medication is for use on external skin surfaces. Do not ingest this medication.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are using the medication without consulting your doctor.

It is important to use this medication exactly as prescribed by your doctor. If you miss a dose, apply it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not apply a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Do not use this medication if you are allergic to acyclovir, valacyclovir, or any of the ingredients of the medication.

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What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is used in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who uses this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people using this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • contact dermatitis
  • itching, stinging, or redness of the genital area
  • mild pain, burning and/or stinging upon application
  • skin rash

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Prevention of recurrence: Applying acyclovir topical to areas when no symptoms are present will not prevent the recurrence of infection. Apply acyclovir topical only at the first appearance of a herpes infection episode.

Protection from infection: Current research studies have not shown that the topical form of acyclovir prevents transmission of infection to other persons.

Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while using this medication, contact your doctor immediately.

Breast-feeding: Acyclovir, when taken as a tablet or injection, is known to pass into breast milk. No information is available on the amount of acyclovir that may appear in breast milk after using the topical form of acyclovir. If you are a breast-feeding mother and are using acyclovir topical, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

What other drugs could interact with this medication?

Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications that you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.