Your hepatitis B symptoms may get worse or become very serious if you stop taking entecavir. Talk with your doctor before stopping this medication. Your doctor will perform liver function tests for several months after you stop entecavir. Tell your doctor immediately if you develop symptoms of worsening liver disease, including persistent nausea, stomach/abdominal pain, dark urine, or yellowing eyes/skin.
Entecavir has rarely caused serious (possibly fatal) liver enlargement and/or lactic acid build-up in the blood (lactic acidosis). Get medical help right away if you develop any of the following symptoms: unusual tiredness (fatigue), severe drowsiness, muscle pain, difficult or rapid breathing, irregular heartbeat.
Lactic acidosis is more likely to occur in patients who have: kidney or liver disease, conditions that may cause a low level of oxygen in the blood or poor circulation (e.g., severe congestive heart failure, recent heart attack, recent stroke), excessive alcohol use, a lack of body fluids (dehydration), X-ray or scanning procedure drugs (contrast agents), major surgery, or a serious infection.
This medication is not recommended if you have both HIV and hepatitis B and are not receiving effective treatment for HIV. This drug does not treat HIV, and it can cause certain HIV medications to become ineffective. Therefore, have an HIV test before starting this medication, and get tested again anytime you may have become infected. Consult your doctor for more details.
See also Warning section.
This medication is used to treat a chronic viral infection of the liver (hepatitis B). It works by slowing the growth of the virus. Entecavir is a nucleoside analog-type (NRTI) medication.
Entecavir is not a cure for hepatitis B and does not prevent the spread of hepatitis B to others through sexual contact or blood/body fluid contamination (e.g., sharing used needles). A series of shots (vaccine) are available to protect uninfected people from hepatitis B virus.
Read the Patient Information Leaflet provided by your pharmacist before you start using entecavir and each time you get a refill. If you have any questions regarding the information, consult your doctor or pharmacist.
Take this medication by mouth on an empty stomach at least 2 hours after a meal and 2 hours before the next meal, usually once daily or as directed by your doctor.
If you are taking entecavir oral liquid, carefully measure your dose with the spoon provided. Hold the spoon in an upright position with the volume marks facing you. Slowly fill the spoon to the mark for your prescribed dose. Swallow the medicine directly from the measuring spoon. Do not dilute or mix the medication with water or other liquids. Rinse the spoon with water after each use.
Take this medication regularly in order to get the most benefit from it. Remember to use it at the same time each day. Do not skip any doses. Dosage is based on your medical condition (including the previous use of the drug lamivudine) and response to treatment. In children, the dosage is also based on weight.
Take this medication exactly as prescribed. Do not change your dose or stop taking entecavir without talking to your doctor. (See Warning section)
Inform your doctor of any new symptoms or if your condition worsens.
See also Warning section.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Before taking entecavir, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: HIV infection, kidney disease.
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Kidney function declines as you grow older. This medication is removed by the kidneys. Therefore, elderly people may be more sensitive to this drug, and to side effects such as lactic acidosis.
This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
Do not share this medication with others.
Laboratory and/or medical tests (e.g., kidney and liver tests) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.
The bottle with the medication should be stored in the original carton to protect from light.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised March 2014. Copyright(c) 2014 First Databank, Inc.
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