Zeffix
How does it work?
Zeffix tablets and oral solution contain the active ingredient lamivudine, which is a type of medicine called a nucleoside analogue. Lamivudine is an antiviral medicine used to treat hepatitis B. (NB. Lamivudine is also used to treat HIV infection, but when used for this purpose, higher doses than those found in Zeffix are needed. See the Epivir factsheet for more information on this use of lamivudine.)
Hepatitis B is a virus that infects the liver and leads to liver damage. Once the virus is inside the liver cells it multiplies. Part of this process involves the virus making copies of its genetic material (DNA). This is achieved by a compound essential to the virus, called viral DNA polymerase. Viral DNA polymerase is a compound known as an enzyme. Lamivudine works by blocking the action of this enzyme. This stops the virus from multiplying.
Lamivudine lowers the amount of hepatitis B virus in the body. This leads to a reduction in liver damage and an improvement in liver function.
What is it used for?
Warning!
Use with caution in
Not to be used in
This medicine should not be used if you are allergic to one or any of its ingredients. Please inform your doctor or pharmacist if you have previously experienced such an allergy.
If you feel you have experienced an allergic reaction, stop using this medicine and inform your doctor or pharmacist immediately.
Pregnancy and Breastfeeding
Certain medicines should not be used during pregnancy or breastfeeding. However, other medicines may be safely used in pregnancy or breastfeeding providing the benefits to the mother outweigh the risks to the unborn baby. Always inform your doctor if you are pregnant or planning a pregnancy, before using any medicine.
Side effects
Medicines and their possible side effects can affect individual people in different ways. The following are some of the side effects that are known to be associated with this medicine. Because a side effect is stated here, it does not mean that all people using this medicine will experience that or any side effect.
The side effects listed above may not include all of the side effects reported by the drug's manufacturer.
For more information about any other possible risks associated with this medicine, please read the information provided with the medicine or consult your doctor or pharmacist.
How can this medicine affect other medicines?
It is important to tell your doctor or pharmacist what medicines you are already taking, including those bought without a prescription and herbal medicines, before you start treatment with this medicine. Similarly, check with your doctor or pharmacist before taking any new medicines while taking this one, to ensure that the combination is safe.
Trimethoprim may increase the blood level of lamivudine. This should not require a dose adjustment unless you have kidney problems, however you should be well monitored by your doctor if you are prescribed trimethoprim or co-trimoxazole (which contains trimethoprim) while taking this medicine.
The manufacturer recommends that this medicine is not used in combination with zalcitabine.
Other medicines containing the same active ingredient
Epivir
contains a higher dose of lamivudine than this medicine and is used to treat HIV infection.
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care or attention by a qualified practitioner. The materials in this web site cannot and should not be used as a basis for diagnosis or choice of treatment. Conditions for use
