
The following information is a summary about Hepsera. It is not intended to replace a doctor's instructions.
What is adefovir?
Adefovir is an antiviral medication. It works by preventing viral cells from multiplying in
the body and infecting new liver cells.
Adefovir is used to treat chronic hepatitis B in adults. This medicine will not cure
hepatitis.
Adefovir may also be used for purposes other than those listed in this medication guide.
What is the most important information I should know about adefovir?
This medication may cause lactic acidosis (the build up of lactic acid in the body).
Lactic acidosis can start slowly and gradually get worse. Symptoms include unusual muscle pain
and weakness, trouble breathing, fast or uneven heart rate, nausea, vomiting, stomach pain, and
numbness or cold feeling in your arms or legs. Contact your doctor at once if you have any of
these symptoms, even if they are only mild. Early signs of lactic acidosis generally get worse
over time and this condition can be fatal.
Adefovir can also cause serious kidney problems, especially if you have kidney disease or
take certain medications.
Your liver symptoms may become severe after you stop taking adefovir, even months
after stopping. Your doctor may want to check your liver function on a regular basis for several
months after you stop taking adefovir. Do not miss any scheduled appointments.
Avoid having unprotected sex or sharing needles, razors, or toothbrushes. Taking
adefovir will not prevent you from passing hepatitis B to other people. Talk with your doctor
about safe methods of preventing hepatitis transmission during sex, such as using a condom and
spermicide. Sharing drug or medicine needles is never safe, even for a healthy person.
Tell your doctor if you have been exposed to HIV, or if you have untreated HIV or
AIDS. Taking medicines to treat chronic hepatitis B can cause HIV infection to become resistant
to the standard HIV and AIDS medications. You may need to be tested for HIV before you start
taking adefovir.
What should I discuss with my healthcare provider before taking adefovir?
Do not use this medication if you are allergic to adefovir.
Before taking adefovir, tell your doctor if you are allergic to any drugs, or if you have
kidney or liver disease.
Tell your doctor if you have been exposed to HIV, or if you have untreated HIV or
AIDS. Taking medicines to treat chronic hepatitis B can cause HIV infection to become resistant
to the standard HIV and AIDS medications. You may need to be tested for HIV before you start
taking adefovir.
This medication may cause lactic acidosis (the build up of lactic acid in the body).
Lactic acidosis can start slowly and gradually get worse. Symptoms include unusual muscle pain
and weakness, trouble breathing, fast or uneven heart rate, nausea, vomiting, stomach pain, and
numbness or cold feeling in your arms or legs. Contact your doctor at once if you have any of
these symptoms, even if they are only mild. Early signs of lactic acidosis generally get worse
over time and this condition can be fatal.
FDA pregnancy category C. This medication may be harmful to an unborn baby. Tell
your doctor if you are pregnant or plan to become pregnant during treatment.
Your name may need to be listed on an antiviral pregnancy registry if you are pregnant
while using this medication. The purpose of this registry is to track the outcome of the
pregnancy and delivery to evaluate whether adefovir had any effect on the baby.
It is not known whether adefovir passes into breast milk or if it could harm a nursing
baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.
How should I take adefovir?
Take this medication exactly as it was prescribed for you. Do not take the medication in
larger amounts, or take it for longer than recommended by your doctor. Follow the directions on
your prescription label.
Take adefovir with a full glass of water.
Adefovir may be taken with or without food.
It is important to use adefovir regularly to get the most benefit. Get your prescription
refilled before you run out of medicine completely.
To be sure this medication is not causing harmful effects, your blood will need to be
tested on a regular basis. Your kidney or liver function may also need to be tested.
Your liver symptoms may become severe after you stop taking adefovir, even months
after stopping. Your doctor may want to check your liver function on a regular basis for several
months after you stop using adefovir. Do not miss any scheduled visits to your doctor.
If your condition worsens after you stop taking adefovir, your doctor may recommend that
you restart this medication or another treatment for hepatitis B.
While taking adefovir, you should remain under the care of a doctor.
Store adefovir at room temperature away from moisture and heat.
What happens if I miss a dose?
Take the missed dose as soon as you remember. If it is almost time for your next dose,
skip the missed dose and take the medicine at your next regularly scheduled time. Do
not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention if you think you have used too much of this
medicine.
Symptoms of an adefovir overdose may include nausea, vomiting, diarrhea, and other
stomach problems.
What should I avoid while taking adefovir?
Avoid having unprotected sex or sharing needles, razors, or toothbrushes. Taking this
medication will not prevent you from passing hepatitis B to other people. Talk with your doctor
about safe methods of preventing hepatitis transmission during sex, such as using a condom and
spermicide. Sharing drug or medicine needles is never safe, even for a healthy person.
Adefovir side effects
Get emergency medical help if you have any of these signs of an allergic
reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have any of these serious side effects:
-
urinating less than usual or not at all;
-
muscle pain, tenderness, or weakness (may occur several
weeks or months after you start taking adefovir);
-
numbness or cold feeling in your arms and legs, trouble
breathing, nausea with vomiting, fast or uneven heart rate, and feeling light-headed or fainting;
or
-
nausea, stomach pain, low fever, loss of appetite, dark
urine, clay-colored stools, jaundice (yellowing of the skin or eyes).
Less serious side effects may be more likely to occur, such as:
-
mild nausea, vomiting, diarrhea, gas, or stomach pain;
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skin rash or itching;
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weakness; or
-
headache.
Side effects other than those listed here may also occur. Talk to your
doctor about any side effect that seems unusual or that is especially bothersome.
What other drugs will affect adefovir?
Before taking adefovir, tell your doctor if you are using any of the following drugs:
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amphotericin B (Fungizone, AmBisome, Amphotec, Abelcet);
-
pentamidine (Nebupent, Pentam);
-
tacrolimus (Prograf);
-
antibiotics such as capreomycin (Capastat), rifampin
(Rifadin, Rimactane, Rifater), vancomycin (Vancocin, Vancoled);
-
antiviral medicines such as acyclovir (Zovirax), cidofovir
(Vistide), or foscarnet (Foscavir);
-
cancer medicine such as aldesleukin (Proleukin),
carmustine (BiCNU, Gliadel), cisplatin (Platinol), ifosfamide (Ifex), oxaliplatin (Eloxatin),
plicamycin (Mithracin), streptozocin (Zanosar), or tretinoin (Vesanoid); or
-
HIV medicines such as abacavir (Ziagen), didanosine
(Videx), efavirenz (Sustiva), emtricitabine (Emtriva), lamivudine (Epivir), stavudine (Zerit),
tenofovir (Viread), zalcitabine (Hivid), zidovudine (Retrovir), or combinations such as Atripla,
Combivir, Epzicom, Trizivir, or Truvada.
If you are using any of these drugs, you may not be able to use
adefovir, or you may need dosage adjustments or special tests during treatment.
There may be other drugs not listed that can affect adefovir. Tell your doctor about all the
prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal
products, and drugs prescribed by other doctors. Do not start using a new medication without
telling your doctor.
Where can I get more information?
-
Your pharmacist has information about adefovir written for health professionals that you
may read.
What does my medication look like?
Adefovir is available with a prescription under then brand name Hepsera. Other brand or
generic formulations may also be available. Ask your pharmacist any questions you have about
this medication, especially if it is new to you.
-
Remember, keep this and all other medicines out of the reach of children, never share
your medicines with others, and use this medication only for the indication prescribed.