Adefovir (Hepsera) is an antiviral medication that's used for the treatment of hepatitis B in people age 12 and older. It's not a first-choice treatment option because the virus can become resistant to adefovir (Hepsera), meaning the medication might stop working well over time. Adefovir (Hepsera) is available as a brand-name and generic tablet that's typically taken once daily. Some side effects of the medication can include weakness, headache, and stomach pain.
Hepatitis B virus (HBV)
Adefovir (Hepsera) is a type of antiviral medication called a nucleoside reverse transcriptase inhibitor (NRTI). It works by inserting itself into the hepatitis B virus's DNA. This blocks the virus from making copies of itself.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Dark urine
general tiredness and weakness
light-colored stools
upper right abdomen or stomach pain
yellow eyes and skin
Less common
Blood in the urine
change in frequency of urination or amount of urine
difficult breathing
drowsiness
increased thirst
loss of appetite
swelling of the feet or lower legs
weakness
Rare
Fast, shallow breathing
general feeling of discomfort
muscle pain or cramping
shortness of breath
sleepiness
unusual tiredness or weakness
Incidence not known
bone fractures, especially of the thigh bone
bone pain
chills
cloudy urine
convulsions
darkened urine
decreased frequency or amount of urine
fast heartbeat
increase in the amount of urine
increased blood pressure
indigestion
lower back or side pain
muscular pain, tenderness, wasting, or weakness
pains in the stomach, side, or abdomen, possibly radiating to the back
swelling of the face, fingers, or lower legs
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Only need to take once a day
Can take with or without food
Available as a lower-cost generic
Not a first-choice medication to treat hepatitis B
High risk of viral resistance to the medication
Might cause buildup of lactic acid in the blood (lactic acidosis)
Take adefovir (Hepsera) at the same time every day. You can take it with or without food since food doesn't affect how well the medication works.
Don't stop taking adefovir (Hepsera) unless your provider tells you to. Stopping the medication too early can cause your HBV to "flare up" in a worse way than before.
If you have kidney problems, make sure you get your blood tests done regularly so your provider can check your kidney health. Pay attention to any changes that your provider makes to your dose. They might tell you to take adefovir (Hepsera) less often to lower your risk of side effects from the medication.
Try to avoid taking nonsteroidal anti-inflammatory drugs (NSAIDs), like ibuprofen (Advil, Motrin) and naproxen (Aleve), long term while you're taking adefovir (Hepsera). NSAIDs and adefovir (Hepsera) can both harm the kidney. So taking these medications together can raise your risk of kidney damage even more.
Don't take adefovir (Hepsera) with tenofovir-containing medications (e.g., Viread, Vemlidy). Adefovir (Hepsera) and tenofovir can both harm the kidney.
Talk to your provider if you're pregnant or have plans to become pregnant. It's not known if adefovir (Hepsera) will harm an unborn baby if it's taken during pregnancy. There's a registry that you can enroll in to monitor your and your baby's health if you take adefovir (Hepsera) during pregnancy. Ask your provider about this program.
Adefovir (Hepsera) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Hepatitis B virus | Stopping adefovir (Hepsera)
Don't stop taking adefovir (Hepsera) unless instructed by your healthcare provider. Your hepatitis B infection could come back and get worse if you stop your treatment. If you have severe liver damage, your liver problem could get worse as well. If you're instructed to stop adefovir (Hepsera) or switch to a different antiviral medication, make sure you get your blood tests done regularly, especially during the first 3 months after stopping. This is how your provider will check your liver health and HBV infection.
Risk factors: HIV infection
Your provider will test you for HIV before you start adefovir (Hepsera) and continuously while you're taking the medication. Adefovir (Hepsera) is only FDA approved to treat HBV and isn't typically used for HIV treatment. Having undiagnosed or untreated HIV while taking HBV treatment, such as adefovir (Hepsera), can cause HIV drug resistance and make the HIV infection harder to treat. If you happen to have HIV and hepatitis B, your provider will recommend a medication regimen that works well to treat both infections.
Risk factors: Poor kidney function | Taking other medications that can damage the kidneys | Taking adefovir (Hepsera) for a long time
Adefovir (Hepsera) can damage your kidneys if you take the medication for a long time. Your risk is higher if you have poor kidney function or are taking other medications that can harm the kidneys. Your provider will order blood tests regularly to check your kidney function and will change your dose if needed.
Risk factors: Obesity | Women | History of liver problems
Although rare, NRTIs including adefovir (Hepsera) can cause life-threatening problems like lactic acidosis (too much lactic acid in the blood) and fatty liver disease. Most cases of these problems have happened in women. Risk factors can also include obesity and long-term NRTI use. Symptoms of lactic acidosis include extreme tiredness, sudden weakness, and fast and shallow breathing, while symptoms of fatty liver disease can include stomach pain. Stop taking adefovir (Hepsera) and get medical help right away if this happens.
The typical dose is 10 mg by mouth once a day with or without food. Your dose might differ if you have kidney problems.
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.
Treatment of HIV infection for people ages 3 months and older - brand and generic Epivir only
Treatment of chronic (long-term) hepatitis B for people ages 2 years and older - brand and generic Epivir HBV only
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