Treats herpes (herpes simplex), including genital herpes, shingles (varicella-zoster), and brain infections (herpes simplex encephalitis) in adults. Also treats herpes simplex infection in newborn babies.
There may be other brand names for this medicine.
When This Medicine Should Not Be Used
You should not use this medicine if you have had an allergic reaction to acyclovir or valacyclovir (Valtrex®).
How to Use This Medicine
- Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given through a needle placed in one of your veins.
- A nurse or other trained health professional will give you this medicine. It may also be given by a home health caregiver.
- This medicine must be given slowly, so the needle will stay in place for about 1 hour.
- You may be taught how to give your medicine at home. Make sure you understand all instructions before giving yourself an injection. Do not use more medicine or use it more often than your doctor tells you to.
- Use a new needle and syringe each time you inject your medicine.
- Never share your medicine with anyone.
If a dose is missed:
- This medicine needs to be given on a fixed schedule. If you miss a dose or forget to use your medicine, call your doctor or pharmacist for instructions.
How to Store and Dispose of This Medicine
- If you store this medicine at home, keep it at room temperature, away from heat, moisture, and direct light. After the medicine powder in the bottle has been mixed with the liquid, store the mixture in the refrigerator in a closed container. Bring it to room temperature before using. This mixture must be used within 12 hours after mixing.
- Throw away used needles in a hard, closed container that the needles cannot poke through. Keep this container away from children and pets.
- Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
- Keep all medicine out of the reach of children.
Drugs and Foods to Avoid
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
- Make sure your doctor knows if you are also taking probenecid (Benemid® or Probalan®).
Warnings While Using This Medicine
- Make sure your doctor knows if you are pregnant or breastfeeding, or if you have kidney or liver disease, a history of electrolyte problems (such as high or low amounts of potassium, calcium, or sodium in your blood), significant breathing problems, or neurologic disorders such as a history of seizures or head injury.
- Avoid becoming dehydrated, because this can increase your risk of serious side effects. You are more likely to become dehydrated if you do not drink enough water every day or if you have vomiting and/or diarrhea.
- Signs of dehydration include increased thirst, dizziness or lightheadedness, dry mouth, and hot or dry skin but little or no sweating. If you have any of these symptoms, tell your doctor.
Possible Side Effects While Using This Medicine
Call your doctor right away if you notice any of these side effects:
- Allergic reaction: Itching or hives, swelling in face or hands, swelling or tingling in the mouth or throat, tightness in chest, trouble breathing
- Black, bloody, or tarry stools
- Decrease in how much or how often you urinate
- Nausea, vomiting, loss of appetite, pain in the upper stomach
- Pain or swelling where the IV needle is placed
- Swelling of face, fingers, feet, or lower legs
- Unusual bleeding or bruising
- Yellow skin or eyes, dark-colored urine or pale stools
If you notice these less serious side effects, talk with your doctor:
- Mild nausea, diarrhea, or stomach upset
- Muscle pain