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.
- This drug is not for use for any reason other than treating smallpox. In a study for another health problem, a larger number of deaths happened in people taking this drug compared to people not taking it. If you have questions, talk with the doctor.
- It is used to treat smallpox.
- 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 are taking any of these drugs: Cidofovir, clarithromycin, cyclosporine, erythromycin, gemfibrozil, rifampin, or drugs to treat HIV or hepatitis C.
- If you are breast-feeding or plan to breast-feed.
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.
- Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
- Have blood work checked as you have been told by the doctor. Talk with the doctor.
- If you have a weak immune system, talk with your doctor. This drug may not work.
- Diarrhea is common with this drug and can be severe. Call your doctor to find out what to do if you have diarrhea or stomach cramps. You will need to take care not to become dehydrated. Do not try to treat diarrhea without first checking with your doctor.
- Some types of cancers have happened in animals. Do not touch broken or crushed tablets or the liquid (suspension). If anyone touches this drug, wash well with soap and water. If this drug gets in the eyes, rinse well with water.
- This drug may lower sperm counts. This may affect being able to father a child. If you have questions, talk with the doctor.
- If your sex partner may get pregnant, you must use a condom while taking this drug and for some time after the last dose. Ask your doctor how long to use a condom. If your partner gets pregnant, call the doctor right away.
- This drug may cause harm to an unborn baby. A pregnancy test will be done before you start this drug to show that you are NOT pregnant.
- If you may become pregnant, you must use birth control while taking this drug and for some time after the last dose. Ask your doctor how long to use birth control. If you get pregnant, call your doctor 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 liver problems like dark urine, tiredness, decreased appetite, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
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:
- Diarrhea, upset stomach, or throwing up.
- Stomach pain.
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.
Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Take this drug on an empty stomach or with a low-fat meal (about 400 calories and 25% fat).
- Swallow whole. Do not chew, break, or crush.
- Take on an empty stomach.
- Shake well before use.
- Measure liquid doses carefully. Use the measuring device that comes with this drug. If there is none, ask the pharmacist for a device to measure this drug.
- After 2 doses are taken, throw away any part not used.
- Those who have feeding tubes may use this drug. Use as you have been told. Flush the feeding tube after this drug is given.
- Call your doctor to find out what to do.
- Store in the original container at room temperature.
- Store in a dry place. Do not store in a bathroom.
- 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.
- Do not freeze.
- 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.
- 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.
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