What side effects are possible with this medication?
A side effect is an unwanted response to a medication when it is taken in normal doses and cannot be anticipated. It can be mild or severe, temporary or permanent, but does not occur in everyone. The following side effects have been reported by at least 3% of people taking this medication. If you develop any of these side effects (or any other side effects not listed here) or they change in intensity, speak to your doctor or pharmacist for advice on managing them and on the risks and benefits of the medication.
- stomach pain
to learn about serious side effects that can potentially occur with any medication. These examples are provided for information purposes only and are not meant to be exhaustive. Always consult your doctor for sound medical advice specific to your particular medication and treatment.
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online or by phone at 1-800-332-1088.
Are there any other precautions or warnings for this medication?
Before you begin taking a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should take this medication.
Hepatitis B transmission: The hepatitis B infection can still be transmitted to other people through blood contamination or sexual contact while you are taking this medication. Continue to take appropriate precautions to prevent the transmission of hepatitis B throughout treatment with adefovir.
HIV and hepatitis B co-infections: If you get or have HIV infection and are not taking medication to treat HIV, adefovir may increase the chance that your HIV infection will not respond to usual treatment. Therefore, it is important to be tested for HIV before starting treatment with adefovir and whenever there is a risk of HIV exposure during treatment.
Kidney problems: This medication may cause kidney problems, especially for people who have or are at risk of developing reduced kidney function (e.g., taking other medications that can cause kidney problems, high blood pressure, diabetes). Your doctor will monitor your kidney function while you are taking this medication. If you have reduced kidney function, you may require longer periods of time between doses.
Lactic acidosis and enlarged liver: Adefovir can cause a condition called lactic acidosis (buildup of lactic acid) together with an enlarged liver. If you experience any of the following symptoms, call your doctor immediately:
- abdominal pain with nausea and vomiting
- dark yellow or brown urine
- difficulty breathing
- dizziness or lightheadedness
- fast or irregular heartbeat
- feeling cold, especially in the arms and legs
- loss of appetite
- pale stools
- unusual muscle pain
- unusual tiredness or weakness
- yellowing of the skin or eyes
Your doctor will periodically monitor you and perform laboratory tests to check your liver function.
Stopping the medication: People with hepatitis may experience a worsening of their condition usually within 12 weeks of stopping this medication. If you and your doctor decide that you should stop taking adefovir, you will need to have regular blood tests to check liver function and hepatitis B virus levels.
Pregnancy: This medication should not be taken during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: It is not known if adefovir passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children: The safety and effectiveness of this medication have not been established for children under 12 years of age.
Seniors: People over the age of 65 may need to be monitored more closely while taking this medication.
What other drugs could interact with this medication?
There may be an interaction between adefovir and any of the following:
- aminoglycosides (e.g., tobramycin, gentamicin)
- nonsteroidal anti-inflammatory drugs (NSAIDS; e.g., ibuprofen, naproxen, ketoprofen)
If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:
- stop taking one of the medications,
- change one of the medications to another,
- change how you are taking one or both of the medications, or
- leave everything as is.
An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.
Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.