Acyclovir

 

Generic Name: acyclovir

What is acyclovir?

Acyclovir is an antiviral drug. It slows the growth and spread of the herpes virus so that the body can fight off the infection. Acyclovir will not cure herpes, but it can lessen the symptoms of the infection.

Acyclovir is used to treat infections caused by herpes viruses. Illnesses caused by herpes viruses include genital herpes, cold sores, shingles, and chicken pox.

Acyclovir may also be used for purposes other than those listed in this medication guide.

 

Important information

Take acyclovir for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated.

Treatment with acyclovir should be started as soon as possible after the first appearance of symptoms (such as tingling, burning, blisters).

 

Herpes infections are contagious and you can infect other people, even while you are being treated with acyclovir. Avoid letting infected areas come into contact with other people. Avoid touching an infected area and then touching your eyes. Wash your hands frequently to prevent passing the infection to others.

 

Before taking this medicine

Do not take this medicine if you are allergic to acyclovir or valacyclovir (Valtrex). Before taking acyclovir, tell your doctor if you are allergic to any drugs, or if you have kidney disease. You may need a dosage adjustment or special tests during treatment.

FDA pregnancy category B. Acyclovir is not expected to be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment. Herpes virus can be passed from an infected mother to her baby during childbirth. If you have genital herpes, it is very important to prevent herpes lesions during your pregnancy so that you do not have a genital lesion when your baby is born. Acyclovir passes into breast milk and may harm a nursing infant. Do not take this medication without telling your doctor if you are breast-feeding a baby.

See also: Pregnancy and breastfeeding warnings (in more detail)

 

How should I take acyclovir?

Take acyclovir exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Follow the directions on your prescription label.

Treatment with acyclovir should be started as soon as possible after the first appearance of symptoms (such as tingling, burning, blisters).

Take each dose with a full glass of water. Drink plenty of water while you are taking acyclovir to keep your kidneys working properly.

Acyclovir can be taken with or without food. Taking acyclovir with food may decrease stomach upset.

Shake the oral suspension (liquid) well just before you measure a dose. To be sure you get the correct dose, measure the liquid with a marked measuring spoon or medicine cup, not with a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one. Take acyclovir for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated. Acyclovir will not treat a viral infection such as the common cold or flu.

Lesions caused by herpes viruses should be kept as clean and dry as possible. Wearing loose clothing may help to prevent irritation of the lesions.

Store acyclovir at room temperature away from moisture and heat.

 

What happens if I miss a dose?

Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at the next regularly scheduled time. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention if you think you have used too much of this medicine.

Overdose symptoms may include seizure (convulsions), hallucinations, and urinating less than usual or not at all.

 

What should I avoid?

Herpes infections are contagious and you can infect other people, even while you are being treated with acyclovir. Avoid letting infected areas come into contact with other people. Avoid touching an infected area and then touching your eyes. Wash your hands frequently to prevent passing the infection to others.

Acyclovir will not prevent the spread of genital herpes. Avoid sexual intercourse or use a latex condom to prevent spreading the virus to others.

 

Acyclovir side effects

Get emergency medical help if you have any of these signs of an allergic reaction to acyclovir: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have any of these serious side effects:

• pain in your lower back;

• urinating less than usual or not at all;

• easy bruising or bleeding; or

• unusual weakness.

Less serious acyclovir side effects may include:

• nausea, vomiting, diarrhea, loss of appetite, stomach pain;

• headache, feeling light-headed; or

• swelling in your hands or feet.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

 

What other drugs will affect acyclovir?

Before taking acyclovir, tell your doctor if you are also taking probenecid (Benemid). If you are using probenecid, you may not be able to use acyclovir, or you may need dosage adjustments or special tests during treatment.

There may be other drugs that can affect acyclovir. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

 

Where can I get more information?

• Your pharmacist can provide more information about acyclovir.

• Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use acyclovir only for the indication prescribed.
• Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.