Generic Name: Foscarnet (fos KAR net)
Brand Name: Foscavir
Medically reviewed by Drugs.com. Last updated on Oct 14, 2020.
- Kidney problems have happened with Foscavir (foscarnet). The doctor will give fluids in a vein to lower the chance of kidney problems. Talk with the doctor.
- Have blood work checked as you have been told by the doctor. Talk with the doctor.
- This medicine may cause seizures in some patients. Talk with the doctor.
- This medicine 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.
Uses of Foscavir:
- 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 Foscavir?
- If you have an allergy to foscarnet or any other part of Foscavir (foscarnet).
- If you are allergic to Foscavir (foscarnet); any part of Foscavir (foscarnet); 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-salt or salt-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.
- If you are breast-feeding or plan to breast-feed.
This is not a list of all drugs or health problems that interact with Foscavir (foscarnet).
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 Foscavir (foscarnet) 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 Foscavir?
For all patients taking Foscavir (foscarnet):
- Tell all of your health care providers that you take Foscavir (foscarnet). 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 Foscavir (foscarnet) affects you.
- If you have seizures, dizziness, or feel sleepy while using Foscavir (foscarnet), avoid driving and doing other tasks or actions that call for you to be alert. Talk with your doctor.
- Seizures have happened with Foscavir (foscarnet). Sometimes, deaths have happened with seizures. Talk with the doctor.
- You will need an ECG before starting Foscavir (foscarnet) and during treatment. Talk with your doctor.
- Use with care in children. Talk with the doctor.
- If you are 65 or older, use Foscavir (foscarnet) with care. You could have more side effects.
- Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using Foscavir (foscarnet) while you are pregnant.
For CMV infections of the eye:
- This medicine 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 medicine is not a cure for herpes infections. Talk with the doctor.
How is this medicine (Foscavir) best taken?
Use Foscavir (foscarnet) 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.
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, a heartbeat that does not feel normal, very bad dizziness or passing out, fast heartbeat, more thirst, seizures, feeling very tired or weak, not hungry, unable to pass urine or change in the amount of urine produced, dry mouth, dry eyes, or very bad 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.
- Low mood (depression).
- Shortness of breath.
- Muscle stiffness.
- Change in eyesight.
- Genital irritation.
- Feeling very tired or weak.
- This medicine 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 Foscavir (foscarnet). 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 Foscavir (foscarnet). 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 Foscavir?
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:
- Upset stomach or throwing up.
- Feeling tired or weak.
- Not hungry.
- Belly pain.
- 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 the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.
If OVERDOSE is suspected:
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.
How do I store and/or throw out Foscavir?
- If you need to store Foscavir (foscarnet) at home, talk with your doctor, nurse, or pharmacist about how to store it.
Consumer information use
- 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. Check with your pharmacist. If you have any questions about Foscavir (foscarnet), 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.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
More about Foscavir (foscarnet)
- Side Effects
- During Pregnancy
- Dosage Information
- Drug Interactions
- Pricing & Coupons
- En Español
- Drug class: miscellaneous antivirals