ZEFFIX 100 mg FILM-COATED TABLETS

Introduction

Package Leaflet: Information for the Patient

Zeffix 100mg film-coated tablets

lamivudine

Read all of this leaflet carefully before you start taking this medicine.

• Keep this leaflet, as you may need to read it again.

• If you have any further questions, ask your doctor or pharmacist.

• This medicine has been prescribed for you only. Do not pass it on to others. It may harm them, even if their signs of illness are the same as yours.
• If you experience any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this leaflet. See section 4.

Contents of the pack

1. What Zeffix is and what it is used for
2. What you need to know before you take Zeffix
3. How to take Zeffix
4. Possible side effects
5. Storage of Zeffix
6. Contents of the pack and other information

1. What Zeffix is and what it is used for

The active substance of Zeffix is lamivudine.

Zeffix is used to treat long-term (chronic) hepatitis B infection in adults.

Zeffix is an antiviral medicine that stops the hepatitis B virus from multiplying and belongs to a group of medicines called nucleoside analogue reverse transcriptase inhibitors (NRTIs).

The hepatitis B virus infects the liver and can cause long-term (chronic) infection, which can lead to liver damage. Zeffix can be used in patients whose liver is damaged but still works normally (compensated liver disease) and in combination with other medicines in patients whose liver is damaged and does not work normally (decompensated liver disease).

Treatment with Zeffix can reduce the amount of hepatitis B virus in your body. This can lead to a reduction in liver damage and an improvement in the function of your liver. Not everyone responds to treatment with Zeffix in the same way. Your doctor will monitor the effectiveness of your treatment with regular blood tests.

2. What you need to know before you take Zeffix

Your doctor should offer you advice and testing to detect HIV infection before you start treatment with lamivudine for hepatitis B infection and during treatment. If you have or get HIV infection, see section 3.

Do not take Zeffix

• if you are allergicto lamivudine or any of the other ingredients of this medicine (listed in section 6).

• Consult your doctorif you think this applies to you.

Warnings and precautions

Some people who take Zeffix or similar medicines have a higher risk of getting serious side effects. You need to know that there is a higher risk:

• if you have ever had other types of liver disease, such as hepatitis C
• if you are overweight(especially if you are a woman)

• Tell your doctorif you have any of these conditions. You may need extra checks, such as blood tests, while you are taking this medicine. For more information about the risks, see Section 4.

Do not stop taking Zeffixwithout your doctor's advice, as there is a risk that your hepatitis may get worse. When you stop taking Zeffix, your doctor will monitor you for at least four months to check for any problems. This will involve taking blood samples to check for increases in liver enzyme levels that may indicate liver damage. See section 3 for more information on how to take Zeffix.

Protect others

Hepatitis B is spread by having sexual contact with someone who has the disease or by transferring infected blood (for example, by sharing needles). Zeffix does not prevent the risk of passing on hepatitis B infection to others. To prevent others from getting hepatitis B:

• Use a condomwhen you have oral or penetrative sex.
• Avoid the risk of blood transfer— for example, do not share needles.

Other medicines and Zeffix

Tell your doctor or pharmacist if you are taking, have recently taken, or might take any other medicines, including those bought without a prescription and herbal medicines.

Remember to tell your doctor or pharmacist if you start taking any other medicines while you are taking Zeffix.

These medicines must not be taken with Zeffix:

• medicines that contain sorbitol or other polyalcohols (such as xylitol, mannitol, lactitol, or maltitol) if taken regularly (usually liquids)
• other medicines that contain lamivudine, used to treat HIV infection(sometimes also called AIDS virus)
• emtricitabine, used to treat HIV infectionor hepatitis B
• cladribine, used to treat hairy cell leukemia

• Tell your doctorif you are being treated with any of these medicines.

Pregnancy

If you are pregnant, think you may be pregnant, or are planning to have a baby:

• Ask your doctorabout the risks and benefits of taking Zeffix during pregnancy.

Do not stop taking Zeffix without your doctor's advice.

Breast-feeding

Zeffix can pass into breast milk. If you are breast-feeding or thinking of breast-feeding:

• Ask your doctorbefore taking Zeffix.

Driving and using machines

Zeffix may make you feel tired, which could affect your ability to drive or use machines.

• Do not drive or use machines unless you are sure it won't affect you.

Zeffix contains sodium

This medicine contains less than 1 mmol sodium (23 mg) per tablet, which is essentially 'sodium-free'.

3. How to take Zeffix

Always take this medicine exactly as your doctor has told you.If you are not sure, check with your doctor or pharmacist.

Keep in regular contact with your doctor

Zeffix helps to control your hepatitis B infection. You need to keep taking it every day to control the infection and prevent it from getting worse.

• Stay in touch with your doctor and do not stop taking Zeffixwithout your doctor's advice.

How much to take

The usual dose of Zeffix is one tablet(100 mg of lamivudine) once a day.

Your doctor may prescribe a lower dose if you have kidney problems. Zeffix oral solution is available for people who need a lower dose than usual or who cannot take tablets.

• Ask your doctorif you are in this situation.

Patients who also have or may get HIV infection

If you have or get HIV infection that is not being treated with medicines, while you are taking lamivudine for hepatitis B infection, the HIV virus can develop resistance to certain HIV medicines and become difficult to treat. Lamivudine is also used to treat HIV infection. Talk to your doctor if you have HIV infection. Your doctor may treat you with another medicine that contains a higher dose of lamivudine, usually 150 mg twice a day, as the lower dose of 100 mg is not enough to treat HIV infection. If you are planning to change your HIV treatment, discuss this change with your doctor before.

• Ask your doctorif you are in this situation.

Swallow the tablet whole with water. Zeffix can be taken with or without food.

If you take more Zeffix than you should

If you accidentally take too much Zeffix, talk to your doctor or pharmacist, or go to the nearest hospital casualty department. If possible, show them the Zeffix pack.

If you forget to take Zeffix

If you miss a dose, take it as soon as you remember. Then continue taking it as before. Do not take a double dose to make up for a forgotten dose.

Do not stop taking Zeffix

Do not stop taking Zeffix without talking to your doctor. There is a risk that your hepatitis may get worse (see section 2). When you stop taking Zeffix, your doctor will monitor you for at least four months to check for any problems. This will involve taking blood samples to check for increases in liver enzyme levels that may indicate liver damage.

4. Possible side effects

Like all medicines, this medicine can cause side effects, although not everybody gets them.

The most common side effects reported with Zeffix in clinical trials were tiredness, infections of the respiratory tract, sore throat, headache, discomfort and stomach pain, nausea, vomiting, and diarrhea, increased liver enzymes, and increased muscle enzymes (see below).

Allergic reaction

This is rare (may affect up to 1 in 1,000 people). The signs include:

• swelling of the eyelids, face, or lips
• difficulty swallowing or breathing.

• See a doctor immediatelyif you get these symptoms. Stop taking Zeffix.

Side effects that are thought to be caused by Zeffix:

A very common side effect(may affect more than 1 in 10people) that may appear in blood tests is:

• an increase in the levels of some liver enzymes (transaminases), which may be a sign of liver inflammation or damage.

A common side effect(may affect up to 1 in 10people) is:

• muscle cramps and muscle pain
• rash or "hives" anywhere on the body.

A common side effect that may appear in blood tests is:

• an increase in the level of a muscle enzyme (creatine phosphokinase) that may be a sign of muscle damage.

A very rare side effect(may affect up to 1 in 10,000 people) is:

• lactic acidosis (excess of lactic acid in the blood).

Other side effects

Other side effects have been reported in a small number of people, but their exact frequency is unknown:

• muscle breakdown
• worsening of liver disease if the hepatitis B virus becomes resistant to Zeffix or if treatment is stopped. This can be fatal in some people.

A side effect that may appear in blood tests is:

• a decrease in the number of blood cells involved in blood clotting (thrombocytopenia).

If you get side effects

• Tell your doctor or pharmacisteven if you think the side effects are not caused by the medicine or are trivial. This includes any possible side effects not listed in this leaflet.

Reporting of side effects

If you get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the national reporting system listed in Appendix V. By reporting side effects, you can help provide more information on the safety of this medicine.

5. Storage of Zeffix

Keep this medicine out of the sight and reach of children.

Do not take this medicine after the expiry date which is stated on the carton and blister.

Do not store above 30°C.

Medicines should not be disposed of via wastewater or household waste. Ask your pharmacist how to dispose of medicines no longer required. These measures will help protect the environment.

6. Contents of the pack and other information

What Zeffix contains

The active substance is lamivudine. Each film-coated tablet contains 100 mg of lamivudine.

The other ingredients are: microcrystalline cellulose, sodium carboxymethylcellulose, magnesium stearate, hypromellose, titanium dioxide, macrogol 400, polysorbate 80, synthetic red and yellow iron oxide.

Appearance and packaging

Zeffix film-coated tablets are presented in child-resistant blisters containing 28 or 84 tablets. The tablets are caramel-colored, capsule-shaped, biconvex, and marked "GX CG5" on one face.

Not all pack sizes may be marketed.

You can ask for more information about this medicine from the local representative of the Marketing Authorisation Holder:

Date of last revision of this leaflet: 05/2025

Detailed information on this medicine is available on the European Medicines Agency web site: http://www.ema.europa.eu