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Acyclovir Injection

What is this medication?

ACYCLOVIR (ay SYE kloe veer) treats infections caused by viruses. This medication will not treat colds, the flu, or infections caused by bacteria.

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This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): Zovirax, Zovirax Powder

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

  • Immune system problems
  • Kidney disease
  • An unusual or allergic reaction to acyclovir, other medications, foods, dyes, or preservatives
  • Pregnant or trying to get pregnant
  • Breastfeeding

How should I use this medication?

This medication is infused into a vein. It is usually given by your care team in a hospital or clinic setting. It may also be given at home.

If you get this medication at home, you will be taught how to prepare and give it. Use exactly as directed. Take it as directed on the prescription label at the same time every day. Keep taking it unless your care team tells you to stop.

It is important that you put your used needles and syringes in a special sharps container. Do not put them in a trash can. If you do not have a sharps container, call your pharmacist or care team to get one.

Talk to your care team about the use of this medication in children. While it may be prescribed for children as young as newborns for selected conditions, precautions do apply.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

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NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medication?

Do not take this medication with any of the following:

  • Cidofovir

This medication may also interact with the following:

  • Adefovir
  • Amphotericin B
  • Certain antibiotics like amikacin, gentamicin, tobramycin, vancomycin
  • Cimetidine
  • Cisplatin
  • Colistin
  • Cyclosporine
  • Foscarnet
  • Lithium
  • Methotrexate
  • Probenecid
  • Tacrolimus

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Your condition will be monitored carefully while you are receiving this medication.

This medication manages the symptoms of the virus. It is possible to spread the virus to others. Avoid contact with others as directed by your care team. Talk to your care team about how to stop the spread of infection.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

  • Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
  • Confusion
  • Hallucinations
  • Kidney injury—decrease in the amount of urine, swelling of the ankles, hands, or feet
  • Seizures

Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):

  • Diarrhea
  • Headache
  • Nausea
  • Upset stomach
  • Vomiting

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children and pets.

If you are using this medication at home, you will be instructed on how to store this medication. Throw away any unused medication after the expiration date on the label.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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Note: Introduction and Additional Common Questions written and medically approved by Cleveland Clinic professionals.

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