Acyclovir, Oral Tablet

Highlights for acyclovir

1. Acyclovir oral tablet is only available as a generic drug. It doesn’t have a brand-name version.
2. Acyclovir is also available as a capsule, suspension, and buccal tablet that you place between your gums and cheek and let dissolve. Other forms it comes in are a cream and an ointment you apply to your skin. In addition, acyclovir is available as an intravenous (IV) drug, which is only given by a healthcare professional.
3. Acyclovir is used to treat viral infections. These include herpes zoster (shingles), genital herpes, and varicella (chickenpox).

What is acyclovir?

Acyclovir oral tablet is a prescription drug that’s only available in a generic form. Generic drugs usually cost less than the brand-name version. In some cases, they may not be available in all strengths or forms as the brand-name drug.

Acyclovir also comes as an oral capsule, oral suspension, buccal tablet, topical cream, and topical ointment. In addition, acyclovir is available as an intravenous drug, which is only given by a healthcare professional. This article focuses on the oral tablet form of acyclovir.

This drug may be used as part of a combination therapy. This means you may need to take it with other medications.

Why it’s used

Acyclovir is used to treat viral infections. These include herpes zoster (shingles), genital herpes, and varicella (chickenpox).

This drug doesn’t cure herpes infections. The herpes virus can stay in your body for a long time and cause symptoms again later.

How it works

Acyclovir belongs to a class of drugs called antivirals. A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions.

How a drug works is called its mechanism of action.

Acyclovir works by stopping the herpes virus from making more copies of itself. It does this by entering the virus’s DNA process and stopping it from building properly. This helps reduce symptoms and makes outbreaks shorter, but it doesn’t get rid of the virus completely.

Herpes infections include cold sores, chickenpox, shingles, or genital herpes. Even with this drug, the herpes virus may still live in your body. Symptoms may occur again later, even after the symptoms of the current infection go away.

Acyclovir side effects

Acyclovir can cause mild or serious side effects. The following lists contain some of the key side effects that may occur while taking acyclovir. These lists do not include all possible side effects.

For more information on the possible side effects of acyclovir, or tips on how to manage a bothersome side effect, talk with your doctor or pharmacist.

Mild side effects

Some of the mild side effects of acyclovir oral tablet include:

• nausea
• vomiting
• diarrhea
• headache
• weakness
• muscle pain
• skin reactions, such as rash, hives, and hair loss

Serious side effects

Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life threatening or if you think you’re having a medical emergency. Serious side effects and their symptoms can include the following:

• Unusual changes in your mood or behavior. Symptoms can include:
  • aggressive behavior
  • unsteady or shaky movements
  • confusion
  • difficulty speaking
  • hallucinations (seeing or hearing something that isn’t there)
• Decrease in your red blood cells and platelets. Symptoms can include:
  • fatigue
• Liver problems.
• Serious skin reactions, such as Stevens-Johnson syndrome. Symptoms can include:
  • hives
  • mouth sores
  • peeling rash
  • blisters
• Changes in your vision.
• Kidney failure. Symptoms can include:
  • kidney or flank pain (pain in your side and back)
  • blood in your urine
• Allergic reaction. Symptoms can include:
  • difficulty breathing
  • swelling of your throat or tongue
  • rash
  • hives

Acyclovir cost and savings

Whether you have health insurance or not, cost may be a factor when you’re considering acyclovir. What you’ll pay for acyclovir may depend on several things, such as your treatment plan and the pharmacy you use.

Here are a few things to consider regarding cost:

• Cost information and savings coupons: You can visit Optum Perks for price estimates of acyclovir. These estimates are based on the use of Optum Perks coupons. Note: Optum Perks coupons cannot be used with insurance copays or benefits.
• Financial assistance: Some websites provide details about drug assistance programs, ways to make the most of your insurance coverage, and links to savings cards and other services. Two such websites are:
  • Medicine Assistance Tool
  • NeedyMeds

Acyclovir may interact with other medications

Acyclovir may interact with several other medications. Different interactions can cause different effects. For instance, some can interfere with how well a drug works, while others can cause increased side effects.

Before taking acyclovir, be sure to tell your doctor and pharmacist about all prescription, over-the-counter, and other drugs you take. Also tell them about any vitamins, herbs, and supplements you use. Sharing this information can help you avoid potential interactions.

If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.

To find out how acyclovir might interact with something else you’re taking, talk with your doctor or pharmacist.

How to take acyclovir

The acyclovir dosage your doctor prescribes will depend on several factors. These include:

• your age
• the condition being treated
• how severe your condition is
• other medical conditions you have
• how you react to the first dose

Typically, your doctor will start you on a low dosage and adjust it over time to reach the dosage that’s right for you. They’ll ultimately prescribe the smallest dosage that provides the desired effect.

The following information describes dosages that are commonly used or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to suit your needs.

Forms and strengths

Generic: Acyclovir

• Form: oral tablet
• Strengths: 400 mg, 800 mg

Dosage for shingles, genital herpes, or chickenpox

Adult dosage (ages 18 to 64 years)

• Shingles typical dosage: 800 mg every 4 hours, five times per day for 7 to 10 days.
• Genital herpes:
  • Typical initial dosage: 200 mg every 4 hours, five times per day, for 10 days.
  • Typical dosage for prevention of recurrent herpes: 400 mg twice per day, every day for up to 12 months. Other dosing plans may include doses ranging from 200 mg three times per day to 200 mg five times per day. Your doctor will decide how long you should take this drug to avoid a flare-up of the infection.
  • Typical dosage for reinfection (flare-up of the infection): 200 mg every 4 hours, five times per day, for 5 days. You should take this drug as soon as the first signs of a flare-up appear.
• Chickenpox typical dosage: Take 800 mg four times per day for 5 days. Start this drug as soon as your first symptom of chickenpox appears. It isn’t known whether this drug is effective if you start it more than 24 hours after the first sign of chickenpox.

Child dosage (ages 2 to 17 years)

• Chickenpox typical dosage:
  • Children who weigh 40 kilograms (88 pounds) or less: 20 mg per kilogram (kg) of body weight, given four times per day for 5 days.
  • Children who weigh more than 40 kg: 800 mg four times per day for 5 days.

Start this drug as soon as the first symptom of chickenpox appears. It isn’t known whether this drug is effective if your child starts it more than 24 hours after the first sign of chickenpox.

Child dosage (ages 0 to 1 year)

It hasn’t been confirmed that acyclovir is safe and effective for children younger than 2 years.

Older adult dosage (ages 65 years and older)

The kidneys of older adults may not work as well as they used to. If you’re an older adult, this can cause your body to process drugs more slowly. As a result, more of a drug stays in your body for a longer time. This increases your risk of side effects.

Your doctor may start you on a lowered dose or a different medication schedule. This can help keep levels of this drug from building up too much in your body.

Take as directed

Acyclovir oral tablet is used for short-term treatment of genital herpes, shingles, and chicken pox. It’s used for long-term treatment of recurring genital herpes. This drug comes with serious risks if you don’t take it as prescribed.

If you stop taking the drug suddenly or don’t take it at all: The symptoms of your infection may not get better or may get worse.

If you miss doses or don’t take the drug on schedule: Your medication may not work as well or may stop working completely. If you’re taking this drug to prevent flare-ups of your infection, a certain amount needs to be in your body at all times. You shouldn’t stop taking this drug without first talking with your doctor.

What to do if you miss a dose: Take your dose as soon as you remember. But if you remember just a few hours before your next scheduled dose, take only one dose. Never try to catch up by taking two doses at once. This could result in dangerous side effects.

If you take too much: You could have dangerous levels of the drug in your body and experience more severe side effects. If you think you’ve taken too much of this drug, call your doctor or local poison control center. If your symptoms are severe, call 911 or go to the nearest emergency room right away.

How to tell if the drug is working: The symptoms of your infection will get better.

Note: The virus you’re using acyclovir to treat may stop responding to the drug, especially if you’ve taken it for a long time. If your symptoms don’t ease, your doctor might do tests or try another treatment.

Acyclovir warnings

This drug comes with several warnings.

Kidney failure

This drug may cause your kidneys to stop working. Tell your doctor if you have any kidney problems before taking this medication.

Low red blood cells and platelets

This drug may cause thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS). These conditions cause dangerously low levels of red blood cells and platelets in your body. This may be fatal. Symptoms can include:

• fatigue
• easy bruising
• prolonged bleeding from cuts
• skin that’s paler than usual
• shortness of breath

Sexual contact

You should not have sexual contact with your partner when you have signs of a genital herpes outbreak. This drug does not cure herpes infections. It may help lower the chance of transmitting herpes to your partner.

However, even having sex using a condom or other barrier method, it’s still possible to transmit genital herpes. Talk with your doctor for information about how to avoid transmitting herpes.

Allergy warning

Acyclovir can cause a severe allergic reaction. Symptoms can include:

• difficulty breathing
• swelling of your throat or tongue
• rash
• hives

Call 911 or go to the nearest emergency room if you develop these symptoms. Don’t take this drug again if you’ve ever had an allergic reaction to it. Taking it again could be fatal.

Warnings for certain groups

For people with kidney problems: If you have kidney problems or a history of kidney disease, your body may not be able to clear this drug well. This may increase the levels of this drug in your body and cause more side effects.

This medication may also decrease your kidney function. This means your kidney disease may worsen. Your doctor will adjust your dose depending on how well your kidneys are working.

For pregnant people: Studies of acyclovir in pregnant animals have not shown a risk to the fetus. But there aren’t enough studies of humans during pregnancy to show whether the drug poses a risk to a fetus.

Talk with your doctor if you’re pregnant or planning to become pregnant. This drug should be used only if the potential benefit justifies the potential risk to the fetus.

Call your doctor right away if you become pregnant while taking this drug.

For people who are breastfeeding: Acyclovir may pass into breast milk and may cause side effects in a child who is breastfed. Talk with your doctor if you breastfeed your baby. You may need to decide whether to stop breastfeeding or stop taking this medication.

For older adults: The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, more of a drug stays in your body for a longer time. This raises your risk of side effects.

For children: This drug hasn’t been studied in children younger than 2 years of age.

Important considerations for taking acyclovir

Keep these considerations in mind if your doctor prescribes acyclovir oral tablet for you.

General

• Take this drug at the time(s) recommended by your doctor.
• You can take acyclovir with or without food. Taking it with food may help reduce upset stomach.
• Do not cut or crush this medication.
• Not every pharmacy stocks this drug. When filling your prescription, be sure to call ahead to make sure your pharmacy carries it.

Storage

• Store this drug at room temperature. Keep it between 59°F and 77°F (15°C and 25°C).
• Keep it away from light.
• Don’t store this medication in moist or damp areas, such as bathrooms.

Refills

A prescription for this medication is refillable. You should not need a new prescription for this medication to be refilled. Your doctor will write the number of refills authorized on your prescription.

Travel

When traveling with your medication:

• Always carry your medication with you. When flying, never put it into a checked bag. Keep it in your carry-on bag.
• Don’t worry about airport X-ray machines. They can’t hurt your medication.
• You may need to show airport staff the pharmacy label for your medication. Always carry the original prescription-labeled box with you.
• Don’t put this medication in your car’s glove compartment or leave it in the car. Be sure to avoid doing this when the weather is very hot or very cold.

Clinical monitoring

You and your doctor should monitor certain health issues. This can help make sure you stay safe while you take this drug. These issues include:

• Kidney function: Your doctor may do blood tests to check how well your kidneys are working. If your kidneys aren’t working well, your doctor may lower your dose of this drug.
• Mental health and behavioral problems: You and your doctor should watch for any unusual changes in your behavior and mood. This drug can cause new mental health and behavior changes. It can also worsen problems you already have.

Your diet

While taking acyclovir, you should drink plenty of water to stay hydrated. This drug can harm your kidneys if you don’t stay well hydrated.

Sun sensitivity

Acyclovir can make your skin more sensitive to the sun. This increases your risk of sunburn. Avoid the sun if you can. If you can’t, be sure to wear protective clothing and apply sunscreen.

Insurance

Many insurance companies require prior authorization for this drug. This means your doctor will need to get approval from your insurance company before your insurance company will pay for the prescription.