Foscarnet

This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.

Brand Names: US

Foscavir

Brand Names: Canada

Vocarvi

Warning

  • Kidney problems have happened with this drug. The doctor will give fluids in a vein to lower the chance of kidney problems. Talk with the doctor.
  • Have your child’s blood work checked often. Talk with your child’s doctor.
  • This drug may cause seizures in some patients. Talk with the doctor.
  • This drug is only approved for use in people with a weak immune system. It is used to treat eye problems caused by cytomegalovirus (CMV). It is also used to treat a type of herpes infection that cannot be treated by another drug. Talk with the doctor.

What is this drug used for?

  • It is used to treat a type of herpes infection that cannot be treated by another drug.
  • It is used to treat a viral infection of the eyes in people who have AIDS.
  • It may be given to your child for other reasons. Talk with the doctor.

What do I need to tell the doctor BEFORE my child takes this drug?

  • If your child is allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell the doctor about the allergy and what signs your child had.
  • If your child has heart problems.
  • If your child is on a low-salt or salt-free diet, talk with your child’s doctor.
  • If your child has kidney disease or is on dialysis.
  • If your child is taking any drugs that can raise the chance of kidney problems. There are many drugs that can do this. Ask the doctor or pharmacist if you are not sure.
  • If your child is taking any drugs that can cause a certain type of heartbeat that is not normal (prolonged QT interval). There are many drugs that can do this. Ask the doctor or pharmacist if you are not sure.

This is not a list of all drugs or health problems that interact with this drug.

Tell the doctor and pharmacist about all of your child’s drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe to give this drug with all of your child’s other drugs and health problems. Do not start, stop, or change the dose of any drug your child takes without checking with the doctor.

What are some things I need to know or do while my child takes this drug?

For all patients taking this drug:

  • Tell all of your child’s health care providers that your child is taking this drug. This includes your child’s doctors, nurses, pharmacists, and dentists.
  • Have your child avoid tasks or actions that call for alertness until you see how this drug affects your child. These are things like riding a bike, playing sports, or using items such as scissors, lawnmowers, electric scooters, toy cars, or motorized vehicles.
  • If your child has seizures, dizziness, or feels sleepy while using this drug, have your child avoid tasks or actions that call for alertness. Talk with the doctor.
  • Seizures have happened with this drug. Sometimes, deaths have happened with seizures. Talk with the doctor.
  • Your child will need an ECG before starting this drug and during treatment. Talk with the doctor.
  • If the patient is a child, use with care. Bone growth may be affected. Talk with your child’s doctor if you have questions.

If your child is pregnant or breast-feeding a baby:

  • Talk with the doctor if your child is pregnant, becomes pregnant, or is breast-feeding a baby. You will need to talk about the benefits and risks to your child and the baby.

For CMV infections of the eye:

  • This drug is not a cure for cytomegalovirus (CMV) infection. Be sure your child stays under the care of the doctor.
  • Get your child an eye exam as you have been told by the doctor.

For herpes infection:

  • This drug is not a cure for herpes infections. Talk with the doctor.

What are some side effects that I need to call my child’s doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your child’s doctor or get medical help right away if your child has any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of fluid and electrolyte problems like mood changes, confusion, muscle pain or weakness, fast or abnormal heartbeat, severe dizziness or passing out, increased thirst, seizures, feeling very tired or weak, decreased appetite, unable to pass urine or change in the amount of urine produced, dry mouth, dry eyes, or severe upset stomach or throwing up.
  • Signs of kidney problems like unable to pass urine, change in how much urine is passed, blood in the urine, or a big weight gain.
  • A burning, numbness, or tingling feeling that is not normal.
  • Trouble controlling body movements.
  • Depression.
  • Shortness of breath.
  • Muscle stiffness.
  • Change in eyesight.
  • Genital irritation.
  • This drug may irritate the vein. If the drug leaks from the vein, it may also cause irritation around that area. Tell your child’s nurse if your child has any redness, burning, pain, swelling, or leaking of fluid where the drug is going into your child’s body.
  • A type of abnormal heartbeat (prolonged QT interval) has happened with this drug. Sometimes, this has led to another type of unsafe abnormal heartbeat (torsades de pointes). Call your child’s doctor right away if your child has a fast or abnormal heartbeat, or if your child passes out.
  • Low white blood cell counts have happened with this drug. This may lead to a higher chance of getting an infection. Call your child’s doctor right away if your child has signs of infection like fever, chills, or sore throat.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your child’s doctor or get medical help if any of these side effects or any other side effects bother your child or do not go away:

  • Anxiety.
  • Headache.
  • Diarrhea, upset stomach, or throwing up.
  • Feeling dizzy, tired, or weak.
  • Decreased appetite.
  • Stomach pain.
  • Sweating a lot.

These are not all of the side effects that may occur. If you have questions about side effects, call your child’s doctor. Call your child’s doctor for medical advice about side effects.

You may report side effects to your national health agency.

How is this drug best given?

Give this drug as ordered by your child’s doctor. Read all information given to you. Follow all instructions closely.

  • It is given as an infusion into a vein over a period of time.
  • Have your child drink lots of noncaffeine liquids every day unless told to drink less liquid by your child’s doctor.

What do I do if my child misses a dose?

  • Call your child’s doctor to find out what to do.

How do I store and/or throw out this drug?

  • If you need to store this drug at home, talk with your child’s doctor, nurse, or pharmacist about how to store it.

General drug facts

  • If your child’s symptoms or health problems do not get better or if they become worse, call your child’s doctor.
  • Do not share your child’s drug with others and do not give anyone else’s drug to your child.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
  • Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your child’s doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.

Last Reviewed Date

2020-06-17

Copyright

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Last Updated

Monday, December 12, 2022