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Drugs

Acyclovir

Acyclovir

Other Names: Zovirax, acyclovir sodium Drug Class: Opportunistic Infections and Coinfections
What is acyclovir?

What is acyclovir?

Acyclovir is an antiviral prescription medicine approved by the U.S. Food and Drug Administration (FDA) to treat and prevent reoccurrence of herpes simplex virus (HSV) infections (including genital herpes) and to treat varicella zoster virus (VZV) diseases (including chicken pox and shingles). Acyclovir is approved in different formulations and strengths for use in specific populations, including in people who are immunocompromised (have a weakened immune system).

HSV and VZV infections are opportunistic infections of HIV. An opportunistic infection is an infection that occurs more frequently or is more severe in people with weakened immune systems—such as those infected with HIV—than in people with healthy immune systems.

Acyclovir can also be used off-label to prevent and treat VZV diseases in people with HIV. Off-label use refers to use of an FDA-approved medicine in a manner different from that described on the medicine label. Good medical practice and the best interests of a patient sometimes require that a medicine be used off-label.

How is acyclovir used in people with HIV?

How is acyclovir used in people with HIV?

The Guidelines for the Prevention and Treatment of Opportunistic infections in HIV-Infected Adults and Adolescents, prepared by the Centers for Disease Control and Prevention (CDC), the National Institutes of Health (NIH), and the HIV Medicine Association of the Infectious Diseases Society of America (IDSA-HIVMA), includes recommendations on the HIV-related uses of acyclovir to:

  • Prevent:
    • Orolabial lesions (cold sores) and genital lesions caused by HSV infection from recurring. This is called secondary prophylaxis or maintenance therapy.
    • Chicken pox in people with HIV at risk of infection from close contact with a person who has active chicken pox or shingles (both are VZV diseases). This is called post-exposure prophylaxis. (This is an off-label use.)
  • Treat:
    • HSV infections, including orolabial lesions and genital lesions.
    • VZV disease, including chicken pox, shingles, and acute retinal necrosis, which is an inflammatory condition that can damage or destroy the retina of the eye. (Treatment for acute retinal necrosis is an off-label use.)

The above list may not include all of the HIV-related uses of acyclovir recommended in the Guidelines for the Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents. Some recommended uses, such as uses in certain rare circumstances, may have been omitted.

What should I tell my health care provider before taking acyclovir?

What should I tell my health care provider before taking acyclovir?

Before taking acyclovir, tell your health care provider:

  • If you are allergic to acyclovir or any other medicines.
  • About any medical conditions you have or have had, for example, diabetes or liver problems.
  • About anything that could affect your ability to take medicines, such as difficulty swallowing pills, difficulty remembering to take a scheduled dose, or any health conditions that may prevent your use of intravenous medicines.
  • If you are pregnant or plan to become pregnant. Whether acyclovir can harm an unborn baby is unknown. Acyclovir should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Talk to your health care provider about possible risks with taking acyclovir when pregnant.
  • If you are breastfeeding or plan to breastfeed. Do not breastfeed if you are infected with HIV.
  • About other prescription and nonprescription medicines, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Acyclovir may affect the way other medicines or products work, and other medicines or products may affect how acyclovir works. Ask your health care provider if there are interactions between acyclovir and the other medicines you take.

Ask your health care provider about possible side effects from acyclovir. Your health care provider will tell you what to do if you have side effects.

How should I take acyclovir?

How should I take acyclovir?

Take acyclovir according to your health care provider’s instructions. Your health care provider will tell you how much acyclovir to take and when to take it. Before you start acyclovir and each time you get a refill, read any printed information that comes with your medicine.

How should acyclovir be stored?

How should acyclovir be stored?

  • Store acyclovir capsules, tablets, and suspension at 59°F to 77°F (15°C to 25°C). Protect acyclovir capsules and tablets from moisture.
  • Store acyclovir injection for intravenous infusion at room temperature, 68°F to 77°F (20°C to 25°C).
  • Do not use acyclovir if the original seal over the container opening is broken or missing.
  • Throw away acyclovir that is no longer needed or expired (out of date). Follow FDA guidelines on how to safely dispose of unused medicine.
  • Keep acyclovir and all medicines out of reach of children.

Where can I find more information about acyclovir?

Where can I find more information about acyclovir?

More information about acyclovir is available:

The above Patient Version drug summary is based on the following FDA label(s): Capsule, suspension, tablet; Injection (solution).

Last Reviewed: May 11, 2017