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

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 you for other reasons. Talk with the doctor.

What do I need to tell my doctor BEFORE I take this drug?

• If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
• If you have heart problems.
• If you are on a low-sodium or sodium-free diet.
• If you have kidney disease or are on dialysis.
• If you are taking any drugs that can raise the chance of kidney problems. There are many drugs that can do this. Ask your doctor or pharmacist if you are not sure.
• If you are 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 your 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 your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take this drug?

For all patients taking this drug:

• Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
• Avoid driving and doing other tasks or actions that call for you to be alert until you see how this drug affects you.
• If you have seizures, dizziness, or feel sleepy while using this drug, avoid driving and doing other tasks or actions that call for you to be alert. Talk with your doctor.
• You will need an ECG before starting this drug and during treatment. Talk with your 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 you are 65 or older, use this drug with care. You could have more side effects.
• Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.

For CMV infections of the eye:

• This drug is not a cure for cytomegalovirus (CMV) infection. Stay under the care of your doctor.
• Have an eye exam as you have been told by your 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 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 doctor or get medical help right away if you have 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 nurse if you have any redness, burning, pain, swelling, or leaking of fluid where the drug is going into your 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 doctor right away if you have a fast or abnormal heartbeat, or if you pass out.
• Low white blood cell counts have happened with this drug. This may lead to a higher chance of getting an infection. Call your doctor right away if you have 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 doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

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

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

You may report side effects to your national health agency.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

How is this drug best taken?

Use this drug as ordered by your 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.
• Drink lots of noncaffeine liquids unless told to drink less liquid by your doctor.

What do I do if I miss a dose?

• Call your 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 doctor, nurse, or pharmacist about how to store it.

General drug facts

• If your symptoms or health problems do not get better or if they become worse, call your doctor.
• Do not share your drugs with others and do not take anyone else’s drugs.
• 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 doctor, nurse, pharmacist, or other health care provider.
• Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this drug, please talk with your 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

2024-05-24

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