Tyzeka is an antiviral medicine that prevents a virus from multiplying in the body and infecting new liver cells.

Tyzeka is used to treat chronic hepatitis B (HBV) in people who are at least 16 years old.

Tyzeka will not cure hepatitis.

Tyzeka may cause a serious condition called lactic acidosis. Get emergency medical help if you have even mild symptoms such as: muscle pain or weakness, numb or cold feeling in your arms and legs, trouble breathing, stomach pain, nausea with vomiting, fast or uneven heart rate, dizziness, or feeling very weak or tired.

Tyzeka can also cause serious liver problems. Call your doctor at once if you have: swelling around your midsection, stomach pain, nausea, loss of appetite, dark urine, clay-colored stools, or jaundice (yellowing of the skin or eyes).

Tyzeka can also cause muscle or nerve problems. Tell your doctor right away if you have numbness, tingling, burning in your arms or legs, trouble walking, or unexplained muscle pain, tenderness, or weakness.

If you have hepatitis B you may develop liver symptoms after you stop taking Tyzeka. Your liver function may need to be checked for several months after you stop using telbivudine.

Tyzeka side effects

Get emergency medical help if you have signs of an allergic reaction to Tyzeka: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Some people develop lactic acidosis while taking telbivudine. Early symptoms may get worse over time and this condition can be fatal. Get emergency medical help if you have even mild symptoms such as:

• muscle pain or weakness;

• numb or cold feeling in your arms and legs;

• trouble breathing;

• feeling dizzy, light-headed, tired, or very weak;

• stomach pain, nausea with vomiting; or

• fast or irregular heart rate.

Call your doctor at once if you have:

• numbness, tingling, burning in your arms or legs, trouble walking;

• fever, unusual tiredness; or

• liver problems - swelling around your midsection, stomach pain, nausea, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Common Tyzeka side effects may include:

• headache, dizziness, feeling tired;

• fever, cough, sore throat;

• muscle or joint pain, back pain;

• nausea, stomach pain, bloating, diarrhea;

• abnormal liver function tests;

• rash; or

• sleep problems (insomnia).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Take Tyzeka exactly as prescribed by your doctor. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Your doctor will perform blood tests to make sure you do not have conditions that would prevent you from safely using this medicine.

Tyzeka may be taken with or without food. Take the medicine at the same time each day.

Tell your doctor if you have trouble swallowing a Tyzeka tablet.

Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

Do not change your doses or medication schedule without your doctor's advice. Every person with HBV should remain under the care of a doctor.

Use Tyzeka regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely.

Store in the original container at room temperature away from moisture and heat. Do not freeze. Keep the bottle tightly closed when not in use.

Do not keep unused Tyzeka that is no longer needed. Throw away any liquid not used within 2 months after you first opened the bottle. Throw away any unused or expired tablets in a closed container or sealed bag. Ask your pharmacist where to locate a community drug take-back disposal program.

Your liver symptoms may become severe after you stop taking Tyzeka, even months later. You will need frequent blood tests to check your liver function during treatment and for several months after you stop using this medicine.

Usual Adult Dose for Chronic Hepatitis B:

600 mg orally once a day
Duration of therapy: Optimum duration not established

Use: For the treatment of chronic HBV infection in patients with evidence of viral replication and either evidence of persistent serum aminotransferase (ALT or AST) elevations or histologically active disease

Usual Pediatric Dose for Chronic Hepatitis B:

16 years or older: 600 mg orally once a day
Duration of therapy: Optimum duration not established

Use: For the treatment of chronic HBV infection in patients with evidence of viral replication and either evidence of persistent serum aminotransferase (ALT or AST) elevations or histologically active disease

You should not take Tyzeka if you are allergic to telbivudine, or if you are also using peginterferon alfa-2b (Pegasys).

To make sure Tyzeka is safe for you, tell your doctor if you have ever had:

• kidney disease;

• other types of hepatitis (C or D);

• a liver transplant;

• allergies;

• HIV or AIDS;

• if you are on a low-salt diet; or

• if you have used any hepatitis B medication that did not work well in treating your condition.

Some people taking Tyzeka develop a serious condition called lactic acidosis. This may be more likely in women, in people who are overweight or have liver disease, and in people who have taken HIV/AIDS medication for a long time. Talk with your doctor about your risk.

Tyzeka is not expected to harm an unborn baby. Tyzeka may not keep you from passing hepatitis B to your unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

If you are pregnant, your name may be listed on a pregnancy registry. This is to track the outcome of the pregnancy and to evaluate any effects of telbivudine on the baby.

It is not known whether telbivudine passes into breast milk or if it could harm a nursing baby. You should not breast-feed while using this medicine.

Tyzeka is not approved for use by anyone younger than 16 years old.

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Taking this medicine will not prevent you from passing HBV to other people. Do not have unprotected sex or share razors or toothbrushes. Talk with your doctor about safe ways to prevent HBV transmission during sex. Sharing drug or medicine needles is never safe, even for a healthy person.

Get emergency medical help if you have signs of an allergic reaction to Tyzeka: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Some people develop lactic acidosis while taking telbivudine. Early symptoms may get worse over time and this condition can be fatal. Get emergency medical help if you have even mild symptoms such as:

• muscle pain or weakness;

• numb or cold feeling in your arms and legs;

• trouble breathing;

• feeling dizzy, light-headed, tired, or very weak;

• stomach pain, nausea with vomiting; or

• fast or irregular heart rate.

Call your doctor at once if you have:

• numbness, tingling, burning in your arms or legs, trouble walking;

• fever, unusual tiredness; or

• liver problems - swelling around your midsection, stomach pain, nausea, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Common Tyzeka side effects may include:

• headache, dizziness, feeling tired;

• fever, cough, sore throat;

• muscle or joint pain, back pain;

• nausea, stomach pain, bloating, diarrhea;

• abnormal liver function tests;

• rash; or

• sleep problems (insomnia).

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Tyzeka may cause serious muscle problems, especially if you use certain medicines at the same time, such as antibiotics or antifungal medicine, anti-malaria medicine, cholesterol-lowering medicine, a steroid, or medicine to prevent organ transplant rejection.

Tell your doctor if you use an interferon such as Intron A, Rebetron, Rebif, or Roferon-A.

Many drugs can interact with telbivudine. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide. Tell your doctor about all your current medicines and any medicine you start or stop using.