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.
Symfi; Symfi Lo
- Hepatitis B has gotten worse when this drug was stopped in some people with hepatitis B. Close follow-up for a few months is needed when therapy is stopped in people who have hepatitis B. Do not stop giving this drug to your child without calling your child’s doctor.
- It is used to treat HIV infection.
- 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 any of these health problems: Kidney disease or liver disease.
- If your child takes any drugs (prescription or OTC, natural products, vitamins) that must not be taken with this drug, like certain drugs that are used for hepatitis C, HIV, or infections. There are many drugs that must not be taken with this drug.
- If your child is taking another drug that has the same drug in it.
- If your child weighs less than 77 pounds (35 kilograms).
If your child is pregnant:
- Do not give this drug to your child if she is in the first trimester of pregnancy.
If your child is breast-feeding a baby:
- Be sure your child does not breast-feed a baby while taking this drug.
This is not a list of all drugs or health problems that interact with this drug.
This drug interacts with many other drugs. The chance of severe, life-threatening, or deadly side effects may be raised. 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.
- 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 blood work checked as you have been told by the doctor. Talk with the doctor.
- Have your child’s urine checked as you have been told by the doctor.
- Hepatitis B testing needs to be done as you were told by the doctor. Talk with the doctor.
- This drug may affect certain lab tests. Tell all of your child’s health care providers and lab workers that your child takes this drug.
- This drug may cause high cholesterol and triglyceride levels. Talk with the doctor.
- Alcohol may interact with this drug. Be sure your child does not drink alcohol.
- Talk with your child’s doctor before your child uses marijuana, other forms of cannabis, or prescription or OTC drugs that may slow your child’s actions.
- This drug is not a cure for HIV. Be sure your child stays under the care of the doctor.
- This drug does not stop the spread of diseases like HIV or hepatitis that are passed through blood. Be sure needles and other things like toothbrushes or razors are not shared.
- Nervous system problems are common with this drug. These may include dizziness, sleepiness, trouble sleeping or focusing, or abnormal dreams. Most of the time, this goes away after 2 to 4 weeks. Giving this drug at bedtime may help with these effects. If your child feels dizzy, sleepy, or has trouble focusing, have your child avoid tasks or actions that call for alertness. Call the doctor if these effects last, they bother your child, or are severe.
- Bone problems like bone pain, soft bones, and thin bones have happened. This may lead to broken bones. Your child may need to have a bone test.
- Give calcium and vitamin D as you were told by your child’s doctor.
- Kidney problems like kidney failure have happened with this drug. Tell your child’s doctor if your child has ever had kidney problems.
- Liver problems have happened with this drug. Sometimes these problems have been severe, leading to liver transplant or death. Liver problems may happen in people with or without liver disease. Talk with the doctor.
- If your child has hepatitis C and HIV, talk with your child’s doctor. Liver function has gotten worse in people who were taking this drug and interferon alfa with or without ribavirin. Sometimes, this has been deadly.
- Rarely, this drug may cause a swollen liver and a buildup of acid in the blood. Sometimes, this may be deadly. The risk may be higher in females, in overweight people, and in people who have taken drugs like this one for a long time.
- A pancreas problem (pancreatitis) has happened in children taking lamivudine with or without other HIV drugs. Sometimes this has been deadly. If you have questions, talk with the doctor.
- If your child is of childbearing age, a pregnancy test will need to be done before starting this drug to make sure your child is not pregnant.
If your child is or may be sexually active:
- This drug does not stop the spread of diseases like HIV or hepatitis that are passed through having sex. Be sure your child does not have any kind of sex without using a latex or polyurethane condom.
- Birth control pills and other hormone-based birth control may not work as well to prevent pregnancy. Be sure your child uses some other kind of birth control also, like a condom, when taking this drug.
- This drug may cause harm to the unborn baby if your child takes it during pregnancy.
- Have your child use birth control while taking this drug and for some time after the last dose. Ask the doctor how long your child must use birth control. If your child becomes pregnant, call the 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 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 kidney problems like unable to pass urine, change in how much urine is passed, blood in the urine, or a big weight gain.
- Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
- Signs of too much lactic acid in the blood (lactic acidosis) like fast breathing, fast heartbeat, a heartbeat that does not feel normal, very bad upset stomach or throwing up, feeling very sleepy, shortness of breath, feeling very tired or weak, very bad dizziness, feeling cold, or muscle pain or cramps.
- Signs of a pancreas problem (pancreatitis) like very bad stomach pain, very bad back pain, or very bad upset stomach or throwing up.
- New or worse behavior or mood changes like depression or thoughts of suicide.
- Bone pain.
- Muscle pain or weakness.
- Joint pain.
- Pain in arms or legs.
- Change in body fat.
- Changes in your child’s immune system can happen when your child starts taking drugs to treat HIV. If your child has an infection that you did not know was there, it may show up when your child takes this drug. Tell your child’s doctor right away if your child has any new signs after starting this drug, even after taking it for several months. This includes signs of infection like fever, sore throat, weakness, cough, or shortness of breath.
- Severe nervous system problems have happened. These may include feeling confused, behavior or mood changes, balance problems, other movement problems, or hallucinations (seeing or hearing things that are not there). Sometimes, this has happened months to years after starting this drug. Call the doctor right away if your child has any of these effects.
- A severe skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis) may happen. It can cause severe health problems that may not go away, and sometimes death. Get medical help right away if your child has signs like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in the mouth, throat, nose, or eyes.
- A type of abnormal heartbeat (prolonged QT interval) can happen with this drug. Call the doctor right away if your child has a fast heartbeat, a heartbeat that does not feel normal, or if your child passes out.
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:
- Back pain.
- Stomach pain or diarrhea.
- Upset stomach or throwing up.
- Feeling tired or weak.
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.
Give this drug as ordered by your child’s doctor. Read all information given to you. Follow all instructions closely.
- Give on an empty stomach.
- Keep giving this drug to your child as you have been told by your child’s doctor or other health care provider, even if your child feels well.
- It is important that your child does not miss or skip a dose of this drug during treatment.
- Give a missed dose as soon as you think about it.
- If it is close to the time for your child’s next dose, skip the missed dose and go back to your child’s normal time.
- Do not give 2 doses at the same time or extra doses.
- If you are not sure what to do if your child misses a dose, call the doctor.
- 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.
- 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.
- 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.
- 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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