Examples

How It Works

Antiviral medications prevent the virus that causes shingles from multiplying. These medications shorten the period of rash, decrease pain during the active stage of the illness, and reduce the possibility of getting complications of shingles, such as postherpetic neuralgia. Antivirals may be taken orally (by mouth) or injected intravenously (in a vein).

Why It Is Used

Anyone who has shingles can use antivirals, but antivirals are particularly beneficial for adults older than 50 and people with weak immune systems. They are also used for people with severe rash and those who have rash near an eye and/or on the forehead.

How Well It Works

Antivirals may reduce the severity of shingles and speed healing. When acyclovir, famciclovir, or valacyclovir are taken within 72 hours of getting shingles, these medicines can significantly reduce the duration of pain associated with shingles. These medicines also reduce the pain caused by postherpetic neuralgia. ^{1, 2}

Side Effects

Antivirals have few side effects but may cause headache, nausea, and loss of appetite.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

Valacyclovir and acyclovir are approved by the U.S. Food and Drug Administration (FDA) for the treatment of shingles.

If you have kidney problems, you may need to take less than the typical dosage of antiviral medication. Before you start antiviral treatment, be sure your health professional is aware of your other medical conditions.

If you have a weakened immune system, as may happen to people with diseases such as HIV or diabetes, your health professional may inject antiviral medications into your vein (intravenously).

Topical antivirals (put on the skin) do not help treat shingles.

Complete the new medication information form (PDF) (What is a PDF document?) to help you understand this medication.