Zovirax

Zovirax is a drug that is commonly prescribed to treat shingles, genital herpes, and chickenpox. These conditions are caused by viruses, and the drug works by preventing the viruses from multiplying. Zovirax is available in a number of forms, including tablets, capsules, and an oral suspension. Common side effects include nausea, diarrhea, and headaches.

 

What Is Zovirax?

Zovirax® (acyclovir) is a prescription medication used to treat the following conditions:
 
This article focuses on the oral forms of Zovirax.
 
(For information on other forms, click Zovirax Cream or Zovirax Ointment.)
 
(Click Zovirax Uses for more information on what the drug is used for, including possible off-label uses.)
 

Who Makes Zovirax?

Zovirax is made by GlaxoSmithKline.
 

How Does Zovirax Work?

Shingles, genital herpes, and chickenpox are caused by viruses. Once a person has been infected with one of these viruses, the virus never goes away. It remains inactive in certain nerve cells of the body, waiting to become active again. Zovirax is an antiviral medication that helps the body fight the infection. It does this by preventing the virus from multiplying.
 

Effects of Zovirax

Several studies have examined how well Zovirax treats shingles, genital herpes, and chickenpox.
 
Shingles
In studies looking at Zovirax for shingles, the drug helped shingles lesions to heal faster and helped reduce pain. Zovirax also helped to prevent nerve pain associated with shingles. Studies suggested that the medication was more effective when started within the first 48 hours after symptoms appeared and worked better in people over 50 years old.
 
Genital Herpes
For people who took Zovirax to treat their first genital herpes infection, the lesions healed more quickly and were painful for a shorter period of time, compared to those who did not take the drug.
 
Studies also showed that Zovirax helps prevent genital herpes outbreaks in people with frequent recurrences (six or more outbreaks per year). In these people, Zovirax reduced the frequency and severity of outbreaks.
 
Chickenpox
In studies, Zovirax helped chickenpox lesions to heal 50 percent faster, reduced the number of lesions, and decreased the chance of fever or loss of appetite. In these studies, the medication was used within 24 hours after the appearance of chickenpox in children.
 

When and How to Take Zovirax

General considerations for when and how to take Zovirax include the following:
 
  • The medication comes in the form of tablets, capsules, and a suspension (oral liquid). Zovirax injection (used for more serious herpes infections), cream, and ointment are also available.
     
  • Zovirax can be taken with or without food. If the medication bothers your stomach, try taking it with food.
     
  • Be sure to shake the liquid form of Zovirax thoroughly before each dose.
     
  • For the medication to work properly, it must be taken as prescribed. Make sure to take Zovirax as prescribed by your healthcare provider.
     

Dosing Information for Zovirax

The dose of Zovirax that your healthcare provider recommends will vary, depending on a number of factors, including:
 
  • Your age and weight
  • The condition being treated
  • Other medications you may be taking
  • Other medical conditions you may have.
     
As is always the case, do not adjust your Zovirax dose unless your healthcare provider specifically instructs you to do so.
 
(Click Zovirax Dosage for more information.)
 

Zovirax Side Effects

As with any medicine, side effects are possible with Zovirax. However, not everyone who takes the drug will experience side effects. In fact, most people tolerate it quite well. If side effects do occur, in most cases, they are minor and either require no treatment or can easily be treated by you or your healthcare provider. Serious side effects are less common.
 
Common side effects of Zovirax include but are not limited to:
 
(Click Side Effects of Zovirax to learn more, including potentially serious side effects that you should report immediately to your healthcare provider. You can also read about a specific Zovirax side effect by clicking Zovirax Hair Loss.)
 

Drug Interactions With Zovirax

Zovirax can potentially interact with a few other medicines (see Zovirax Drug Interactions).
 

Zovirax: What Should I Tell My Healthcare Provider?

You should talk with your healthcare provider prior to taking Zovirax if you have:
 
  • Kidney disease, including kidney failure (renal failure)
  • Any allergies, including allergies to food, dyes, or preservatives.
     
Also, let your healthcare provider know if you are:
 
Make sure to tell your healthcare provider about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements.
 
(Click Zovirax Warnings and Precautions to learn more, including information on who should not take the drug.)
 

What If I Take an Overdose of Zovirax?

People who take too much Zovirax may have overdose symptoms that could include:
 
  • Agitation
  • Coma
  • Seizures
  • Lethargy
  • Kidney damage.
     
If you happen to overdose on Zovirax, seek immediate medical attention.
 
(Click Zovirax Overdose for more information.)
 

What Should I Do If I Miss a Dose of Zovirax?

If you do not take your Zovirax as scheduled, take your missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not take a double dose.
 

Strengths of Zovirax

Zovirax tablets are available in the following strengths:
 
  • Zovirax 400 mg
  • Zovirax 800 mg.
     
Zovirax capsules are available in one strength -- Zovirax 200 mg.
 
Zovirax suspension is available in one strength -- Zovirax Suspension 200 mg per 5 mL (200 mg per teaspoonful).
 

Is There a Generic Version of Zovirax?

Currently, both brand-name and generic Zovirax versions are licensed for sale (see Generic Zovirax).
 
Add this article to your Favorites     Email this article     Print
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD
Last reviewed by: Kristi Monson, PharmD;